diff --git a/VERSION b/VERSION
index 5174c53..b2fb78a 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-3.16
+3.18
diff --git a/devLib/lcd.c b/devLib/lcd.c
index 0491bb9..1bb0807 100644
--- a/devLib/lcd.c
+++ b/devLib/lcd.c
@@ -27,16 +27,12 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>
+#include <stdbool.h>
 
 #include <wiringPi.h>
 
 #include "lcd.h"
 
-#ifndef	TRUE
-#  define	TRUE	(1==1)
-#  define	FALSE	(1==2)
-#endif
-
 // HD44780U Commands
 
 #define	LCD_CLEAR	0x01
@@ -483,9 +479,9 @@ int lcdInit (const int rows, const int cols, const int bits,
 
 // Rest of the initialisation sequence
 
-  lcdDisplay     (lcdFd, TRUE) ;
-  lcdCursor      (lcdFd, FALSE) ;
-  lcdCursorBlink (lcdFd, FALSE) ;
+  lcdDisplay     (lcdFd, true) ;
+  lcdCursor      (lcdFd, false) ;
+  lcdCursorBlink (lcdFd, false) ;
   lcdClear       (lcdFd) ;
 
   putCommand (lcd, LCD_ENTRY   | LCD_ENTRY_ID) ;
diff --git a/devLib/maxdetect.c b/devLib/maxdetect.c
index 69537bd..b864891 100644
--- a/devLib/maxdetect.c
+++ b/devLib/maxdetect.c
@@ -24,6 +24,7 @@
 
 #include <sys/time.h>
 #include <stdio.h>
+#include <stdbool.h>
 //#include <stdlib.h>
 //#include <unistd.h>
 
@@ -31,11 +32,6 @@
 
 #include "maxdetect.h"
 
-#ifndef	TRUE
-#  define	TRUE	(1==1)
-#  define	FALSE	(1==2)
-#endif
-
 
 /*
  * maxDetectLowHighWait:
@@ -58,7 +54,7 @@ static int maxDetectLowHighWait (const int pin)
   {
     gettimeofday (&now, NULL) ;
     if (timercmp (&now, &timeUp, >))
-      return FALSE ;
+      return false ;
   }
 
 // Wait for it to go HIGH
@@ -72,10 +68,10 @@ static int maxDetectLowHighWait (const int pin)
   {
     gettimeofday (&now, NULL) ;
     if (timercmp (&now, &timeUp, >))
-      return FALSE ;
+      return false ;
   }
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -110,7 +106,7 @@ static unsigned int maxDetectClockByte (const int pin)
 /*
  * maxDetectRead:
  *	Read in and return the 4 data bytes from the MaxDetect sensor.
- *	Return TRUE/FALSE depending on the checksum validity
+ *	Return true/false depending on the checksum validity
  *********************************************************************************
  */
 
@@ -136,7 +132,7 @@ int maxDetectRead (const int pin, unsigned char buffer [4])
 // Now wait for sensor to pull pin low
 
   if (!maxDetectLowHighWait (pin))
-    return FALSE ;
+    return false ;
 
 // and read in 5 bytes (40 bits)
 
@@ -165,7 +161,7 @@ int maxDetectRead (const int pin, unsigned char buffer [4])
 // reading is probably bogus.
 
   if ((took.tv_sec != 0) || (took.tv_usec > 16000))
-    return FALSE ;
+    return false ;
 
   return checksum == localBuf [4] ;
 }
@@ -196,7 +192,7 @@ int readRHT03 (const int pin, int *temp, int *rh)
   {
     *rh   = lastRh ;
     *temp = lastTemp ;
-    return TRUE ;
+    return true ;
   }
 
 // Set timeout for next read
@@ -214,7 +210,7 @@ int readRHT03 (const int pin, int *temp, int *rh)
     result = maxDetectRead (pin, buffer) ;
 
   if (!result)
-    return FALSE ;
+    return false ;
 
   *rh   = (buffer [0] * 256 + buffer [1]) ;
   *temp = (buffer [2] * 256 + buffer [3]) ;
@@ -229,10 +225,10 @@ int readRHT03 (const int pin, int *temp, int *rh)
 //	(which does seem to happen - no realtime here)
 
   if ((*rh > 999) || (*temp > 800) || (*temp < -400))
-    return FALSE ;
+    return false ;
 
   lastRh   = *rh ;
   lastTemp = *temp ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/documentation/deutsch/functions.md b/documentation/deutsch/functions.md
index 0c86b55..f0c87b3 100644
--- a/documentation/deutsch/functions.md
+++ b/documentation/deutsch/functions.md
@@ -473,7 +473,7 @@ static void wfi(struct WPIWfiStatus wfiStatus, void* userdata) {
       edgeType = "falling";
   else
       edgeType = "none";
-  printf("gpio BCM = %d, IRQ edge = %s, timestamp = %lld microseconds, timenow = %lld, diff = %lld\n", wfiStatus.gpioPin, edgeType, wfiStatus.timeStamp_us, timenow, diff);
+  printf("gpio BCM = %d, IRQ edge = %s, timestamp = %lld microseconds, timenow = %lld, diff = %lld\n", wfiStatus.pinBCM, edgeType, wfiStatus.timeStamp_us, timenow, diff);
   if (toggle == 0) {
     digitalWrite (OUTpin, HIGH);
     toggle = 1;
@@ -500,19 +500,19 @@ int main (void)
 
   printf("Testing waitForInterrupt on both edges IRQ @ GPIO%d, timeout is %d\n", IRQpin, TIMEOUT);
   struct WPIWfiStatus wfiStatus = waitForInterrupt2(IRQpin, INT_EDGE_BOTH, TIMEOUT, BOUNCETIME_WFI);
-  if (wfiStatus.status < 0) {
+  if (wfiStatus.statusOK < 0) {
     printf("waitForInterrupt returned error\n");
     pinMode(OUTpin, INPUT);
     return 0;
   }
-  else if (wfiStatus.status == 0) {
+  else if (wfiStatus.statusOK == 0) {
     printf("waitForInterrupt timed out\n\n");
   }
   else {
     if (wfiStatus.edge == INT_EDGE_FALLING)
-        printf("waitForInterrupt: GPIO pin %d falling edge fired at %lld microseconds\n\n", wfiStatus.gpioPin, wfiStatus.timeStamp_us);
+        printf("waitForInterrupt: GPIO pin %d falling edge fired at %lld microseconds\n\n", wfiStatus.pinBCM, wfiStatus.timeStamp_us);
     else
-        printf("waitForInterrupt: GPIO pin %d rising edge fired at %lld microseconds\n\n", wfiStatus.gpioPin, wfiStatus.timeStamp_us);
+        printf("waitForInterrupt: GPIO pin %d rising edge fired at %lld microseconds\n\n", wfiStatus.pinBCM, wfiStatus.timeStamp_us);
   }
   
   printf("Testing IRQ @ GPIO%d on both edges and bouncetime %d microseconds. Toggle LED @ GPIO%d on IRQ.\n\n", IRQpin, BOUNCETIME, OUTpin);
@@ -809,8 +809,8 @@ int wiringPiSPISetupMode(int channel, int speed, int mode)
 int wiringPiSPIxSetupMode(const int number, const int channel, const int speed, const int mode)
 ```
 
-``number``: SPI Nummer (typisch 0, bei Compute Modul 0-7).  
-``channel``: SPI Kanal (typisch 0 oder 1, bei Compute Modul 0-3).  
+``number``: SPI Nummer (typisch 0, bei Compute Modul 0-6).  
+``channel``: SPI Kanal (typisch 0 oder 1, bei Compute Modul oder entsprechenden overlay 0-4).  
 ``speed``: SPI Taktrate.  
 ``mode``: SPI Modus (https://www.kernel.org/doc/Documentation/spi/spidev).  
 ``Rückgabewert``:  Datei Handle zum SPI-Bus  
diff --git a/documentation/english/functions.md b/documentation/english/functions.md
index f13874a..f1ec746 100644
--- a/documentation/english/functions.md
+++ b/documentation/english/functions.md
@@ -470,7 +470,7 @@ static void wfi(struct WPIWfiStatus wfiStatus, void* userdata) {
       edgeType = "falling";
   else
       edgeType = "none";
-  printf("gpio BCM = %d, IRQ edge = %s, timestamp = %lld microseconds, timenow = %lld, diff = %lld\n", wfiStatus.gpioPin, edgeType, wfiStatus.timeStamp_us, timenow, diff);
+  printf("gpio BCM = %d, IRQ edge = %s, timestamp = %lld microseconds, timenow = %lld, diff = %lld\n", wfiStatus.pinBCM, edgeType, wfiStatus.timeStamp_us, timenow, diff);
   if (toggle == 0) {
     digitalWrite (OUTpin, HIGH);
     toggle = 1;
@@ -497,19 +497,19 @@ int main (void)
 
   printf("Testing waitForInterrupt on both edges IRQ @ GPIO%d, timeout is %d\n", IRQpin, TIMEOUT);
   struct WPIWfiStatus wfiStatus = waitForInterrupt2(IRQpin, INT_EDGE_BOTH, TIMEOUT, BOUNCETIME_WFI);
-  if (wfiStatus.status < 0) {
+  if (wfiStatus.statusOK < 0) {
     printf("waitForInterrupt returned error\n");
     pinMode(OUTpin, INPUT);
     return 0;
   }
-  else if (wfiStatus.status == 0) {
+  else if (wfiStatus.statusOK == 0) {
     printf("waitForInterrupt timed out\n\n");
   }
   else {
     if (wfiStatus.edge == INT_EDGE_FALLING)
-        printf("waitForInterrupt: GPIO pin %d falling edge fired at %lld microseconds\n\n", wfiStatus.gpioPin, wfiStatus.timeStamp_us);
+        printf("waitForInterrupt: GPIO pin %d falling edge fired at %lld microseconds\n\n", wfiStatus.pinBCM, wfiStatus.timeStamp_us);
     else
-        printf("waitForInterrupt: GPIO pin %d rising edge fired at %lld microseconds\n\n", wfiStatus.gpioPin, wfiStatus.timeStamp_us);
+        printf("waitForInterrupt: GPIO pin %d rising edge fired at %lld microseconds\n\n", wfiStatus.pinBCM, wfiStatus.timeStamp_us);
   }
 
   printf("Testing IRQ @ GPIO%d on both edges and bouncetime %d microseconds. Toggle LED @ GPIO%d on IRQ.\n\n", IRQpin, BOUNCETIME, OUTpin);
@@ -798,8 +798,8 @@ int wiringPiSPISetupMode(int channel, int speed, int mode);
 int wiringPiSPIxSetupMode(const int number, const int channel, const int speed, const int mode);
 ```
 
-``number``: SPI number (typically 0, on Compute Module 0-7).  
-``channel``: SPI channel (typically 0 or 1, on Compute Module 0-3).  
+``number``: SPI number (typically 0, on Compute Module 0-6).  
+``channel``: SPI channel (typically 0 or 1, on Compute Module or the corresponding overlay 0-4).  
 ``speed``: SPI clock speed in Hz (500,000 to 32,000,000).  
 ``mode``: SPI mode ([www.kernel.org/doc/Documentation/spi/spidev](https://www.kernel.org/doc/Documentation/spi/spidev)).  
 ``Return Value``:  File handle to the SPI bus, or -1 on error.
diff --git a/examples/Gertboard/vumeter.c b/examples/Gertboard/vumeter.c
index 9643ace..5117a11 100644
--- a/examples/Gertboard/vumeter.c
+++ b/examples/Gertboard/vumeter.c
@@ -18,16 +18,12 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <sys/time.h>
 
 #include <wiringPi.h>
 #include <gertboard.h>
 
-#ifndef	TRUE
-#define	TRUE	(1==1)
-#define	FALSE	(!TRUE)
-#endif
-
 #define	B_SIZE	1000
 #define	S_SIZE	 128
 
diff --git a/examples/PiFace/ladder.c b/examples/PiFace/ladder.c
index 4f08a6f..2c37473 100644
--- a/examples/PiFace/ladder.c
+++ b/examples/PiFace/ladder.c
@@ -7,17 +7,13 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <unistd.h>
 #include <math.h>
 
 #include <wiringPi.h>
 #include <piFace.h>
 
-#ifndef	TRUE
-#  define	TRUE	(1==1)
-#  define	FALSE	(1==2)
-#endif
-
 #undef	DEBUG
 
 #define	NUM_LEDS	 8
@@ -244,7 +240,7 @@ void ledOnAction (void)
   if (digitalRead (PIFACE) == LOW)
   {
     chargeCapacitor () ;
-    ledBargraph (vCap, TRUE) ;
+    ledBargraph (vCap, true) ;
   }
 }
 
@@ -264,7 +260,7 @@ void ledOffAction (void)
   if (digitalRead (PIFACE) == LOW)
   {
     vCap = vCapLast = 0.0 ;
-    ledBargraph (vCap, FALSE) ;
+    ledBargraph (vCap, false) ;
 
 // Wait until we release the button
 
@@ -300,7 +296,7 @@ int main (void)
 
 // LED ON:
 
-    (void)ledBargraph (vCap, TRUE) ;
+    (void)ledBargraph (vCap, true) ;
     then = millis () + ledOnTime ;
     while (millis () < then)
     {
@@ -323,7 +319,7 @@ int main (void)
 
 // LED OFF:
 
-    (void)ledBargraph (vCap, FALSE) ;
+    (void)ledBargraph (vCap, false) ;
     then = millis () + ledOffTime ;
     while (millis () < then)
     {
diff --git a/examples/PiGlow/piGlow1.c b/examples/PiGlow/piGlow1.c
index b04dc30..06a4f51 100644
--- a/examples/PiGlow/piGlow1.c
+++ b/examples/PiGlow/piGlow1.c
@@ -25,6 +25,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <poll.h>
 
 #include <wiringPi.h>
@@ -32,11 +33,6 @@
 
 #define	PIGLOW_BASE	533
 
-#ifndef	TRUE
-#  define TRUE  (1==1)
-#  define FALSE (!TRUE)
-#endif
-
 
 /*
  * keypressed: clearKeypressed:
diff --git a/examples/PiGlow/piglow.c b/examples/PiGlow/piglow.c
index b83be61..a0c28ce 100644
--- a/examples/PiGlow/piglow.c
+++ b/examples/PiGlow/piglow.c
@@ -26,11 +26,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
-
-#ifndef	TRUE
-#  define TRUE  (1==1)
-#  define FALSE (!TRUE)
-#endif
+#include <stdbool.h>
 
 #include <wiringPi.h>
 #include <piGlow.h>
@@ -81,7 +77,7 @@ int main (int argc, char *argv [])
 
 // Initialise the piGlow devLib
 
-  piGlowSetup (FALSE) ;
+  piGlowSetup (false) ;
 
   if (argc == 1)
     failUsage () ;
diff --git a/examples/clock.c b/examples/clock.c
index a6b6567..30c3941 100644
--- a/examples/clock.c
+++ b/examples/clock.c
@@ -35,6 +35,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <unistd.h>
 #include <string.h>
@@ -45,11 +46,6 @@
 #include <wiringPi.h>
 #include <lcd128x64.h>
 
-#ifndef	TRUE
-#  define	TRUE	(1==1)
-#  define	FALSE	(1==2)
-#endif
-
 double clockRadius ;
 double thickness, barLen ;
 int maxX, maxY ;
@@ -130,15 +126,15 @@ void drawClockFace (void)
   double d, px1, py1, px2, py2 ;
 
   lcd128x64clear (0) ;
-  lcd128x64circle (0,0, clockRadius, 1, TRUE) ;
-  lcd128x64circle (0,0, clockRadius - thickness, 0, TRUE) ;
+  lcd128x64circle (0,0, clockRadius, 1, true) ;
+  lcd128x64circle (0,0, clockRadius - thickness, 0, true) ;
 
 // The four big indicators for 12,15,30 and 45
 
-  lcd128x64rectangle (- 3,  clockRadius - barLen, 3,  clockRadius,     1, TRUE) ;	// 12
-  lcd128x64rectangle (clockRadius - barLen, 3,  clockRadius, -3, 1, TRUE) ;	// 3
-  lcd128x64rectangle (- 3, -clockRadius + barLen, 3, -clockRadius, 1, TRUE) ;	// 6
-  lcd128x64rectangle (-clockRadius + barLen, 3, -clockRadius, -3, 1, TRUE) ;	// 9
+  lcd128x64rectangle (- 3,  clockRadius - barLen, 3,  clockRadius,     1, true) ;	// 12
+  lcd128x64rectangle (clockRadius - barLen, 3,  clockRadius, -3, 1, true) ;	// 3
+  lcd128x64rectangle (- 3, -clockRadius + barLen, 3, -clockRadius, 1, true) ;	// 6
+  lcd128x64rectangle (-clockRadius + barLen, 3, -clockRadius, -3, 1, true) ;	// 9
 
 
 // Smaller 5 and 1 minute ticks
diff --git a/examples/lcd-adafruit.c b/examples/lcd-adafruit.c
index 7600aaf..925564e 100644
--- a/examples/lcd-adafruit.c
+++ b/examples/lcd-adafruit.c
@@ -26,6 +26,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <unistd.h>
 #include <string.h>
 #include <time.h>
@@ -34,11 +35,6 @@
 #include <mcp23017.h>
 #include <lcd.h>
 
-#ifndef	TRUE
-#  define	TRUE	(1==1)
-#  define	FALSE	(1==2)
-#endif
-
 
 // Defines for the Adafruit Pi LCD interface board
 
@@ -251,7 +247,7 @@ int main (int argc, char *argv[])
 {
   int colour ;
   int cols = 16 ;
-  int waitForRelease = FALSE ;
+  int waitForRelease = false ;
 
   struct tm *t ;
   time_t tim ;
@@ -287,13 +283,13 @@ int main (int argc, char *argv[])
   lcdPuts     (lcdHandle, "User Char: ") ;
   lcdPutchar  (lcdHandle, 2) ;
 
-  lcdCursor      (lcdHandle, TRUE) ;
-  lcdCursorBlink (lcdHandle, TRUE) ;
+  lcdCursor      (lcdHandle, true) ;
+  lcdCursorBlink (lcdHandle, true) ;
 
   waitForEnter () ;
 
-  lcdCursor      (lcdHandle, FALSE) ;
-  lcdCursorBlink (lcdHandle, FALSE) ;
+  lcdCursor      (lcdHandle, false) ;
+  lcdCursorBlink (lcdHandle, false) ;
 
   speedTest () ;
 
@@ -320,7 +316,7 @@ int main (int argc, char *argv[])
       if ((digitalRead (AF_UP) == LOW) || (digitalRead (AF_DOWN) == LOW))
 	continue ;
       else
-	waitForRelease = FALSE ;
+	waitForRelease = false ;
     }
 
     if (digitalRead (AF_UP) == LOW)	// Pushed
@@ -329,7 +325,7 @@ int main (int argc, char *argv[])
       if (colour == 8)
 	colour = 0 ;
       setBacklightColour (colour) ;
-      waitForRelease = TRUE ;
+      waitForRelease = true ;
     }
 
     if (digitalRead (AF_DOWN) == LOW)	// Pushed
@@ -338,7 +334,7 @@ int main (int argc, char *argv[])
       if (colour == -1)
 	colour = 7 ;
       setBacklightColour (colour) ;
-      waitForRelease = TRUE ;
+      waitForRelease = true ;
     }
 
   }
diff --git a/examples/lcd.c b/examples/lcd.c
index b006173..9584550 100644
--- a/examples/lcd.c
+++ b/examples/lcd.c
@@ -38,6 +38,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <stdint.h>
 
 #include <unistd.h>
@@ -47,10 +48,6 @@
 #include <wiringPi.h>
 #include <lcd.h>
 
-#ifndef	TRUE
-#  define	TRUE	(1==1)
-#  define	FALSE	(1==2)
-#endif
 
 static unsigned char newChar [8] = 
 {
@@ -247,13 +244,13 @@ int main (int argc, char *argv[])
   lcdPuts     (lcdHandle, "User Char: ") ;
   lcdPutchar  (lcdHandle, 2) ;
 
-  lcdCursor      (lcdHandle, TRUE) ;
-  lcdCursorBlink (lcdHandle, TRUE) ;
+  lcdCursor      (lcdHandle, true) ;
+  lcdCursorBlink (lcdHandle, true) ;
 
   waitForEnter () ;
 
-  lcdCursor      (lcdHandle, FALSE) ;
-  lcdCursorBlink (lcdHandle, FALSE) ;
+  lcdCursor      (lcdHandle, false) ;
+  lcdCursorBlink (lcdHandle, false) ;
   lcdClear       (lcdHandle) ;
 
   for (;;)
diff --git a/examples/spiSpeed.c b/examples/spiSpeed.c
index cfadfe7..09cdce7 100644
--- a/examples/spiSpeed.c
+++ b/examples/spiSpeed.c
@@ -25,6 +25,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <unistd.h>
 #include <stdint.h>
 #include <string.h>
@@ -36,9 +37,6 @@
 #include <wiringPi.h>
 #include <wiringPiSPI.h>
 
-#define	TRUE	(1==1)
-#define	FALSE	(!TRUE)
-
 #define	SPI_CHAN		0
 #define	NUM_TIMES		100
 #define	MAX_SIZE		(1024*1024)
@@ -78,7 +76,7 @@ int main (void)
     printf ("|   MHz |   Size | mS/Trans |      TpS |    Mb/Sec | Latency mS |\n") ;
     printf ("+-------+--------+----------+----------+-----------+------------+\n") ;
 
-    spiFail = FALSE ;
+    spiFail = false ;
     spiSetup (speed * 1000000) ;
     for (size = 1 ; size <= MAX_SIZE ; size *= 2)
     {
@@ -89,7 +87,7 @@ int main (void)
 	if (wiringPiSPIDataRW (SPI_CHAN, myData, size) == -1)
 	{
 	  printf ("SPI failure: %s\n", strerror (errno)) ;
-	  spiFail = TRUE ;
+	  spiFail = true ;
 	  break ;
 	}
       end = millis () ;
diff --git a/gpio/gpio.1 b/gpio/gpio.1
index 4d76671..e99b66a 100644
--- a/gpio/gpio.1
+++ b/gpio/gpio.1
@@ -282,7 +282,7 @@ Please report bugs to https://github.com/WiringPi/WiringPi/issues
 
 .SH COPYRIGHT
 
-Copyright (c) 2012-2025 Gordon Henderson and contributors
+Copyright (c) 2012–2019 Gordon Henderson; 2019–2026 Contributors
 .br
 This is free software; see the source for copying conditions. There is NO
 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
diff --git a/gpio/gpio.c b/gpio/gpio.c
index b5f0182..bf7d23d 100644
--- a/gpio/gpio.c
+++ b/gpio/gpio.c
@@ -2,7 +2,7 @@
  * gpio.c:
  *	Swiss-Army-Knife, Set-UID command-line interface to the Raspberry
  *	Pi's GPIO.
- *	Copyright (c) 2012-2025 Gordon Henderson and contributors
+ *	Copyright (c) 2012–2019 Gordon Henderson; 2019–2026 Contributors
  ***********************************************************************
  * This file is part of wiringPi:
  *	https://github.com/WiringPi/WiringPi/
@@ -25,6 +25,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <ctype.h>
 #include <string.h>
@@ -51,11 +52,6 @@ extern void doReadall    (void) ;
 extern void doAllReadall (void) ;
 extern void doQmode      (int argc, char *argv []) ;
 
-#ifndef TRUE
-#  define	TRUE	(1==1)
-#  define	FALSE	(1==2)
-#endif
-
 #define	PI_USB_POWER_CONTROL	38
 #define	I2CDETECT		"i2cdetect"
 #define	MODPROBE		"modprobe"
@@ -920,7 +916,7 @@ static void doVersion (char *argv [])
 
   wiringPiVersion (&vMaj, &vMin) ;
   printf ("gpio version: %d.%d\n", vMaj, vMin) ;
-  printf ("Copyright (c) 2012-2025 Gordon Henderson and contributors\n") ;
+  printf ("Copyright (c) 2012–2019 Gordon Henderson; 2019–2026 Contributors\n") ;
   printf ("This is free software with ABSOLUTELY NO WARRANTY.\n") ;
   printf ("For details type: %s -warranty\n", argv [0]) ;
   printf ("\n") ;
@@ -992,12 +988,12 @@ int main (int argc, char *argv [])
   if (getenv ("WIRINGPI_DEBUG") != NULL)
   {
     printf ("gpio: wiringPi debug mode enabled\n") ;
-    wiringPiDebug = TRUE ;
+    wiringPiDebug = true ;
   }
   if (getenv ("GPIO_DEBUG") != NULL)
   {
     printf ("gpio: gpio debug mode enabled\n") ;
-    gpioDebug = TRUE ;
+    gpioDebug = true ;
   }
 
   if (argc == 1)
@@ -1037,7 +1033,7 @@ int main (int argc, char *argv [])
   if (strcasecmp (argv [1], "-warranty") == 0)
   {
     printf ("gpio version: %s\n", VERSION) ;
-    printf ("Copyright (c) 2012-2025 Gordon Henderson and contributors\n") ;
+    printf ("Copyright (c) 2012–2019 Gordon Henderson; 2019–2026 Contributors\n") ;
     printf ("\n") ;
     printf ("    This program is free software; you can redistribute it and/or modify\n") ;
     printf ("    it under the terms of the GNU Leser General Public License as published\n") ;
@@ -1159,7 +1155,7 @@ int main (int argc, char *argv [])
       exit (EXIT_FAILURE) ;
     }
 
-    if (!loadWPiExtension (argv [0], argv [2], TRUE))
+    if (!loadWPiExtension (argv [0], argv [2], true))
     {
       fprintf (stderr, "%s: Extension load failed: %s\n", argv [0], strerror (errno)) ;
       exit (EXIT_FAILURE) ;
@@ -1209,8 +1205,8 @@ int main (int argc, char *argv [])
   else if (strcasecmp (argv [1], "i2cd"     ) == 0) doI2Cdetect  (argv [0]) ;
   else if (strcasecmp (argv [1], "reset"    ) == 0) doReset      (argv [0]) ;
   else if (strcasecmp (argv [1], "wb"       ) == 0) doWriteByte  (argc, argv) ;
-  else if (strcasecmp (argv [1], "rbx"      ) == 0) doReadByte   (argc, argv, TRUE) ;
-  else if (strcasecmp (argv [1], "rbd"      ) == 0) doReadByte   (argc, argv, FALSE) ;
+  else if (strcasecmp (argv [1], "rbx"      ) == 0) doReadByte   (argc, argv, true) ;
+  else if (strcasecmp (argv [1], "rbd"      ) == 0) doReadByte   (argc, argv, false) ;
   else if (strcasecmp (argv [1], "clock"    ) == 0) doClock      (argc, argv) ;
   else if (strcasecmp (argv [1], "wfis"     ) == 0) doWfi2       (argc, argv) ;
   else if (strcasecmp (argv [1], "wfi"      ) == 0) doWfi        (argc, argv) ;
diff --git a/gpio/readall.c b/gpio/readall.c
index 6e2aa18..d75c414 100644
--- a/gpio/readall.c
+++ b/gpio/readall.c
@@ -1,7 +1,7 @@
 /*
  * readall.c:
  *	The readall functions - getting a bit big, so split them out.
- *	Copyright (c) 2012-2024 Gordon Henderson and contributors
+ *	Copyright (c) 2012–2019 Gordon Henderson; 2019–2026 Contributors
  ***********************************************************************
  * This file is part of wiringPi:
  *	https://github.com/WiringPi/WiringPi/
@@ -24,6 +24,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <ctype.h>
 #include <string.h>
@@ -37,11 +38,6 @@
 
 extern int wpMode ;
 
-#ifndef TRUE
-#  define       TRUE    (1==1)
-#  define       FALSE   (1==2)
-#endif
-
 /*
  * doReadallExternal:
  *	A relatively crude way to read the pins on an external device.
diff --git a/gpio/test/gpio_test1_piface1.sh b/gpio/test/gpio_test1_piface1.sh
new file mode 100755
index 0000000..5840830
--- /dev/null
+++ b/gpio/test/gpio_test1_piface1.sh
@@ -0,0 +1,90 @@
+#!/bin/bash
+
+echo -e "🔧 Starting relay unit test for MCP23S17@Piface unit test hw\n\n"
+
+# set pin 200–207 as output
+for i in {200..207}; do
+  gpio -x mcp23s17:200:0:0 mode $i out
+done
+
+# set pin 208–215 as input
+for i in {208..215}; do
+  gpio -x mcp23s17:200:0:0 mode $i in
+  gpio -x mcp23s17:200:0:0 mode $i up
+done
+
+
+# Define relay output addresses and corresponding feedback input addresses
+relay_addresses=(200 201 207 206)
+feedback_addresses=(214 215 212 213)
+
+for round in {1..3}; do
+echo -e "🔄 Round $round / 3\n"
+
+# Loop through each relay
+for i in "${!relay_addresses[@]}"; do
+    out=${relay_addresses[$i]}
+    in=${feedback_addresses[$i]}
+
+    echo "➡️  Relay/IO write test $((i+1)): Address $out → Feedback at $in"
+
+    # Turn ON
+    gpio -x mcp23s17:200:0:0 write "$out" 1
+    sleep 0.5
+    feedback_on=$(gpio -x mcp23s17:200:0:0 read "$in")
+
+    if [ "$feedback_on" -eq 0 ]; then
+        echo "✅ ON Test passed: Feedback is LOW as expected."
+    else
+        echo "❌ ON Test failed: Feedback is HIGH."
+    fi
+
+    # Turn OFF
+    gpio -x mcp23s17:200:0:0 write "$out" 0
+    sleep 0.5
+    feedback_off=$(gpio -x mcp23s17:200:0:0 read "$in")
+
+    if [ "$feedback_off" -eq 1 ]; then
+        echo "✅ OFF Test passed: Feedback is HIGH as expected."
+    else
+        echo "❌ OFF Test failed: Feedback is LOW."
+    fi
+
+    echo -e "\n"
+    sleep 0.5
+
+done
+    for addr in {208..211}; do
+
+    echo "🔃 Pullup resistor test address $addr: "
+     gpio -x mcp23s17:200:0:0 mode "$addr" up
+    sleep 0.5
+     feedback_on=$(gpio -x mcp23s17:200:0:0 read "$addr")
+
+    if [ "$feedback_on" -eq 1 ]; then
+        echo "✅ PULLUP Test passed: Feedback is HIGH as expected."
+    else
+        echo "❌ PULLUP Test failed: Feedback is LOW."
+    fi
+    sleep 0.5
+ 
+     gpio -x mcp23s17:200:0:0 mode "$addr" down 
+    sleep 0.5
+     feedback_on=$(gpio -x mcp23s17:200:0:0 read "$addr")
+
+    if [ "$feedback_on" -eq 1 ]; then
+        echo "✅ PULLDOWN Test passed: Feedback is LOW as expected."
+    else
+        echo "❌ PULLDOW Test failed: Feedback is HIGH."
+    fi
+
+    echo -e "\n"
+    sleep 0.5
+
+
+done
+
+done
+
+#echo "🧹 Cleanup complete. All relays turned OFF."
+
diff --git a/version.h b/version.h
index 5ea1e8c..5d9ebc5 100644
--- a/version.h
+++ b/version.h
@@ -1,3 +1,3 @@
-#define VERSION "3.16"
+#define VERSION "3.18"
 #define VERSION_MAJOR 3
-#define VERSION_MINOR 16
+#define VERSION_MINOR 18
diff --git a/wiringPi/ads1115.c b/wiringPi/ads1115.c
index 44e53cb..2e927f2 100644
--- a/wiringPi/ads1115.c
+++ b/wiringPi/ads1115.c
@@ -35,6 +35,7 @@
 #include <byteswap.h>
 #include <stdio.h>
 #include <stdint.h>
+#include <stdbool.h>
 
 #include <wiringPi.h>
 #include <wiringPiI2C.h>
@@ -278,7 +279,7 @@ int ads1115Setup (const int pinBase, int i2cAddr)
   int fd ;
 
   if ((fd = wiringPiI2CSetup (i2cAddr)) < 0)
-    return FALSE ;
+    return false ;
 
   node = wiringPiNewNode (pinBase, 8) ;
 
@@ -289,5 +290,5 @@ int ads1115Setup (const int pinBase, int i2cAddr)
   node->analogWrite  = myAnalogWrite ;
   node->digitalWrite = myDigitalWrite ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/bmp180.c b/wiringPi/bmp180.c
index bf6c209..2b7e8ac 100644
--- a/wiringPi/bmp180.c
+++ b/wiringPi/bmp180.c
@@ -30,6 +30,7 @@
 
 #include <unistd.h>
 #include <stdint.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <math.h>
 
@@ -192,7 +193,7 @@ int bmp180Setup (const int pinBase)
   struct wiringPiNodeStruct *node ;
 
   if ((fd = wiringPiI2CSetup (I2C_ADDRESS)) < 0)
-    return FALSE ;
+    return false ;
 
   node = wiringPiNewNode (pinBase, 4) ;
 
@@ -233,5 +234,5 @@ int bmp180Setup (const int pinBase)
   p1 = 1.0 - 7357.0 * pow (2.0, -20.0) ;
   p2 = 3038.0 * 100.0 * pow (2.0,  -36.0) ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/drcNet.c b/wiringPi/drcNet.c
index 88ff655..79d71c6 100644
--- a/wiringPi/drcNet.c
+++ b/wiringPi/drcNet.c
@@ -24,6 +24,7 @@
 
 #include <stdio.h>
 #include <stdint.h>
+#include <stdbool.h>
 #include <unistd.h>
 #include <sys/types.h>
 #include <sys/socket.h>
@@ -342,12 +343,12 @@ int drcSetupNet (const int pinBase, const int numPins, const char *ipAddress, co
   struct wiringPiNodeStruct *node ;
 
   if ((fd = _drcSetupNet (ipAddress, port, password)) < 0)
-    return FALSE ;
+    return false ;
 
   len = sizeof (struct drcNetComStruct) ;
 
   if (setsockopt (fd, SOL_SOCKET, SO_RCVLOWAT, (void *)&len, sizeof (len)) < 0)
-    return FALSE ;
+    return false ;
 
   node = wiringPiNewNode (pinBase, numPins) ;
 
@@ -361,5 +362,5 @@ int drcSetupNet (const int pinBase, const int numPins, const char *ipAddress, co
   node->digitalWrite     = myDigitalWrite ;
   node->pwmWrite         = myPwmWrite ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/drcSerial.c b/wiringPi/drcSerial.c
index 6ffc2b1..45288e3 100644
--- a/wiringPi/drcSerial.c
+++ b/wiringPi/drcSerial.c
@@ -23,6 +23,7 @@
  */
 
 #include <stdio.h>
+#include <stdbool.h>
 #include <time.h>
 #include <string.h>
 #include <errno.h>
@@ -151,7 +152,7 @@ int drcSetupSerial (const int pinBase, const int numPins, const char *device, co
   struct wiringPiNodeStruct *node ;
 
   if ((fd = serialOpen (device, baud)) < 0)
-    return FALSE ;
+    return false ;
 
   delay (10) ;	// May need longer if it's an Uno that reboots on the open...
 
@@ -160,7 +161,7 @@ int drcSetupSerial (const int pinBase, const int numPins, const char *device, co
   while (serialDataAvail (fd))
     (void)serialGetchar (fd) ;
 
-  ok = FALSE ;
+  ok = false ;
   for (tries = 1 ; (tries < 5) && (!ok) ; ++tries)
   {
     serialPutchar (fd, '@') ;		// Ping
@@ -170,7 +171,7 @@ int drcSetupSerial (const int pinBase, const int numPins, const char *device, co
       {
         if (serialGetchar (fd) == '@')
         {
-          ok = TRUE ;
+          ok = true ;
           break ;
         }
       }
@@ -179,7 +180,7 @@ int drcSetupSerial (const int pinBase, const int numPins, const char *device, co
   if (!ok)
   {
     serialClose (fd) ;
-    return FALSE ;
+    return false ;
   }
 
   node = wiringPiNewNode (pinBase, numPins) ;
@@ -192,5 +193,5 @@ int drcSetupSerial (const int pinBase, const int numPins, const char *device, co
   node->digitalWrite    = myDigitalWrite ;
   node->pwmWrite        = myPwmWrite ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/ds18b20.c b/wiringPi/ds18b20.c
index c4ec4fd..b12b247 100644
--- a/wiringPi/ds18b20.c
+++ b/wiringPi/ds18b20.c
@@ -29,6 +29,7 @@
 
 #include <unistd.h>
 #include <stdint.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <string.h>
 #include <malloc.h>
@@ -123,7 +124,7 @@ int ds18b20Setup (const int pinBase, const char *deviceId)
 // Allocate space for the filename
 
   if ((fileName = malloc (strlen (W1_PREFIX) + strlen (W1_POSTFIX) + strlen (deviceId) + 1)) == NULL)
-    return FALSE ;
+    return false ;
 
   sprintf (fileName, "%s%s%s", W1_PREFIX, deviceId, W1_POSTFIX) ;
 
@@ -132,7 +133,7 @@ int ds18b20Setup (const int pinBase, const char *deviceId)
   free (fileName) ;
 
   if (fd < 0)
-    return FALSE ;
+    return false ;
 
 // We'll keep the file open, to make access a little faster
 //	although it's very slow reading these things anyway )-:
@@ -142,5 +143,5 @@ int ds18b20Setup (const int pinBase, const char *deviceId)
   node->fd         = fd ;
   node->analogRead = myAnalogRead ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/gtest/.gitignore b/wiringPi/gtest/.gitignore
new file mode 100644
index 0000000..b868581
--- /dev/null
+++ b/wiringPi/gtest/.gitignore
@@ -0,0 +1,2 @@
+bin
+googletest-main
diff --git a/wiringPi/gtest/Makefile b/wiringPi/gtest/Makefile
new file mode 100644
index 0000000..16ce2f8
--- /dev/null
+++ b/wiringPi/gtest/Makefile
@@ -0,0 +1,92 @@
+CXX      := g++
+CXXFLAGS := -std=c++17 -Wall -Wextra -Werror -g \
+	-Igoogletest-main/googletest/include -Igoogletest-main/googlemock/include
+LDFLAGS  := -pthread
+WIRING_PI_LIBS := -lwiringPi
+
+# Where to download googletest
+GTEST_URL := https://github.com/google/googletest/archive/refs/heads/main.zip
+GTEST_ZIP := googletest.zip
+GTEST_DIR := googletest-main
+
+# Output directory
+BIN_DIR := bin
+
+# Helper program
+RUN_ISR_SRC := run_isr.cpp
+RUN_ISR_BIN := $(BIN_DIR)/run_isr
+
+# Need BCM17 <-> BCM18 connection
+TEST_SRCS := \
+    test_isr_both.cpp \
+    test_isr_conflict_between_processes.cpp \
+    test_isr_falling.cpp \
+    test_isr_restart.cpp \
+    test_isr_restart2.cpp \
+    test_isr_rising.cpp \
+    test_isr_rising2.cpp
+
+# Derive test binaries (in bin/)
+TEST_BINS := $(addprefix $(BIN_DIR)/, $(TEST_SRCS:.cpp=))
+
+# gtest/gmock sources
+GTEST_SRCS := $(GTEST_DIR)/googletest/src/gtest-all.cc
+GMOCK_SRCS := $(GTEST_DIR)/googlemock/src/gmock-all.cc
+GTEST_MAIN := $(GTEST_DIR)/googletest/src/gtest_main.cc
+GTEST_INCLUDES := -I$(GTEST_DIR)/googletest/include -I$(GTEST_DIR)/googlemock/include
+
+GTEST_OBJS := $(GTEST_SRCS:.cc=.o)
+GMOCK_OBJS := $(GMOCK_SRCS:.cc=.o)
+GTEST_MAIN_OBJ := $(GTEST_MAIN:.cc=.o)
+
+# Default: build everything
+all: $(GTEST_DIR) $(BIN_DIR) $(TEST_BINS) $(RUN_ISR_BIN)
+
+# Rule: build normal test binaries
+$(filter-out $(BIN_DIR)/test_conflict_between_processes,$(TEST_BINS)): $(BIN_DIR)/%: %.cpp $(GTEST_OBJS) $(GMOCK_OBJS) $(GTEST_MAIN_OBJ)
+	$(CXX) $(CXXFLAGS) $< $(GTEST_OBJS) $(GMOCK_OBJS) $(GTEST_MAIN_OBJ) -o $@ $(LDFLAGS) $(WIRING_PI_LIBS)
+
+# Special case: test_conflict_between_processes depends on run_isr
+$(BIN_DIR)/test_conflict_between_processes: test_conflict_between_processes.cpp $(GTEST_OBJS) $(GMOCK_OBJS) $(GTEST_MAIN_OBJ) $(RUN_ISR_BIN)
+	$(CXX) $(CXXFLAGS) $< $(GTEST_OBJS) $(GMOCK_OBJS) $(GTEST_MAIN_OBJ) -o $@ $(LDFLAGS) $(WIRING_PI_LIBS)
+
+# Build run_isr
+$(RUN_ISR_BIN): $(RUN_ISR_SRC) | $(BIN_DIR)
+	$(CXX) $(CXXFLAGS) $< -o $@ $(WIRING_PI_LIBS)
+
+# Ensure bin directory exists
+$(BIN_DIR):
+	mkdir -p $(BIN_DIR)
+
+# Download googletest if not already present
+$(GTEST_DIR):
+	@echo "Downloading GoogleTest..."
+	curl -L $(GTEST_URL) -o $(GTEST_ZIP)
+	unzip -q $(GTEST_ZIP)
+	rm -f $(GTEST_ZIP)
+
+# Generic rules for compiling gtest/gmock sources
+%.o: %.cc
+	$(CXX) $(CXXFLAGS) $(GTEST_INCLUDES) -I$(GTEST_DIR)/googletest -I$(GTEST_DIR)/googlemock -c $< -o $@
+
+# Run all tests
+test: all
+	@failed=0; \
+	for t in $(TEST_BINS); do \
+	    echo "Running $$t..."; \
+	    ./$$t || failed=1; \
+	done; \
+	if [ $$failed -eq 0 ]; then \
+	    echo "✅ All tests passed."; \
+	else \
+	    echo "❌ Some tests failed."; \
+	    exit 1; \
+	fi
+
+clean:
+	rm -f $(TEST_BINS) $(RUN_ISR_BIN)
+
+distclean: clean
+	rm -rf $(GTEST_DIR) $(BIN_DIR)
+
+.PHONY: all clean distclean test
\ No newline at end of file
diff --git a/wiringPi/gtest/README.md b/wiringPi/gtest/README.md
new file mode 100644
index 0000000..b061c05
--- /dev/null
+++ b/wiringPi/gtest/README.md
@@ -0,0 +1,26 @@
+## Quick Start
+
+g++ is required to build the test cases.
+
+Connect wPi pin 1 (BCM 18) and wPi pin 0 (BCM 17) to run ISR tests.
+Also, wPi pin 6 (BCM 25) should be unconnected.
+
+Run `make test` or do following to run the test:
+
+```
+make googletest-main
+make -j 4
+make test
+```
+
+To clean up the environment:
+
+```
+make clean
+```
+
+## Dependencies
+
+Googletest is downloaded during
+the build for the first time. The downloaded items are in directory `googletest-main`. `make clean` keeps this directory.  Run `make distclean`
+to erase all built images including googletest.
diff --git a/wiringPi/gtest/run_isr.cpp b/wiringPi/gtest/run_isr.cpp
new file mode 100644
index 0000000..9937946
--- /dev/null
+++ b/wiringPi/gtest/run_isr.cpp
@@ -0,0 +1,31 @@
+/*
+ * Helper program of test_conflict_between_processes.
+ *
+ * The program configures ISR on pin 1 (BCM 18) and polls for a termination request.
+ */
+#include <stdint.h>
+#include <stdio.h>
+#include <wiringPi.h>
+
+#define LISTENER_PIN 1  // BCM 18
+
+static uint8_t ok_to_stop = 0;
+static void noop() {
+  fprintf(stderr, "interrupted\n");
+  ok_to_stop = 1;
+}
+
+int main(int, char *[]) {
+  fprintf(stderr, "start\n");
+  wiringPiSetup();
+  if (wiringPiISR(LISTENER_PIN, INT_EDGE_RISING, noop)) {
+    fprintf(stderr, "failed to start listener\n");
+    return -1;
+  }
+  fprintf(stderr, "start listening\n");
+
+  while (!ok_to_stop) {
+    delay(1000);
+  }
+  fprintf(stderr, "bye\n");
+}
\ No newline at end of file
diff --git a/wiringPi/gtest/test_isr_both.cpp b/wiringPi/gtest/test_isr_both.cpp
new file mode 100644
index 0000000..a404e73
--- /dev/null
+++ b/wiringPi/gtest/test_isr_both.cpp
@@ -0,0 +1,51 @@
+#include <gtest/gtest.h>
+#include <time.h>
+#include <wiringPi.h>
+
+#define TRIGGER_PIN  0  // BCM 17
+#define LISTENER_PIN 1  // BCM 18
+
+/**
+ * Tests ISR for both edges.
+ */
+class ISRBoth : public ::testing::Test {
+ public:
+  static void SetUpTestSuite() {
+    wiringPiSetup();
+    pinMode(TRIGGER_PIN, OUTPUT);
+    digitalWrite(TRIGGER_PIN, LOW);
+    wiringPiISR(LISTENER_PIN, INT_EDGE_BOTH, ISRBoth::TriggerCount);
+    delay(100);
+  }
+
+  static uint32_t count;
+  static void TriggerCount() { ++count; }
+
+ protected:
+  virtual void SetUp() { count = 0; }
+
+  virtual void TearDown() {
+    digitalWrite(TRIGGER_PIN, LOW);
+    delay(10);
+  }
+};
+
+uint32_t ISRBoth::count = 0;
+
+TEST_F(ISRBoth, Fundamental) {
+  EXPECT_EQ(count, 0u);
+  digitalWrite(TRIGGER_PIN, HIGH);
+  delay(10);
+  EXPECT_EQ(count, 1u);
+  digitalWrite(TRIGGER_PIN, LOW);
+  delay(10);
+  EXPECT_EQ(count, 2u);
+}
+
+TEST_F(ISRBoth, ThreeTriggers) {
+  for (int i = 0; i < 5; ++i) {
+    digitalWrite(TRIGGER_PIN, (i + 1) % 2);
+    delay(10);
+  }
+  EXPECT_EQ(count, 5u);
+}
\ No newline at end of file
diff --git a/wiringPi/gtest/test_isr_conflict_between_processes.cpp b/wiringPi/gtest/test_isr_conflict_between_processes.cpp
new file mode 100644
index 0000000..2ac955c
--- /dev/null
+++ b/wiringPi/gtest/test_isr_conflict_between_processes.cpp
@@ -0,0 +1,68 @@
+#include <gtest/gtest.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <time.h>
+#include <unistd.h>
+#include <wiringPi.h>
+
+#define TRIGGER_PIN  0  // BCM 17
+#define LISTENER_PIN 1  // BCM 18
+#define ANOTHER_LISTENER_PIN 6  // BCM 25
+
+static void *remote_isr(void *) {
+  std::system("./bin/run_isr");
+  return NULL;
+}
+
+/**
+ * Tests ISR setup conflict between two processes.
+ *
+ * Another program 'run_isr' starts first that occupies the pin 31 for an ISR.
+ * This program should fail to start ISR on the same pin.
+ */
+class ISRConflict : public ::testing::Test {
+ public:
+  static void SetUpTestSuite() {
+    wiringPiSetup();
+    digitalWrite(TRIGGER_PIN, LOW);
+
+    pthread_t tid;
+    pthread_create(&tid, NULL, remote_isr, NULL);
+    delay(1000);
+  }
+
+  static void TearDownTestSuite() {
+      delay(1000);
+  }
+
+  static uint32_t count;
+
+  static void TriggerCount() { ++count; }
+  static void TriggerCount2(WPIWfiStatus, void *userdata) {
+    ++*(uint32_t *)userdata;
+  }
+
+ protected:
+  virtual void SetUp() { count = 0; }
+
+  virtual void TearDown() {
+    digitalWrite(TRIGGER_PIN, LOW);
+    delay(10);
+  }
+};
+
+uint32_t ISRConflict::count = 0;
+
+TEST_F(ISRConflict, TestConflictBetweenProcesses) {
+  // The ISRs should fail to start because run_isr is listening on the
+  // same port
+  EXPECT_EQ(
+      wiringPiISR(LISTENER_PIN, INT_EDGE_FALLING, ISRConflict::TriggerCount),
+      -1);
+  EXPECT_EQ(wiringPiISR2(LISTENER_PIN, INT_EDGE_FALLING,
+                         ISRConflict::TriggerCount2, 0, &ISRConflict::count),
+            -1);
+
+  // to exit run_isr
+  digitalWrite(TRIGGER_PIN, HIGH);
+}
diff --git a/wiringPi/gtest/test_isr_falling.cpp b/wiringPi/gtest/test_isr_falling.cpp
new file mode 100644
index 0000000..ee52e6a
--- /dev/null
+++ b/wiringPi/gtest/test_isr_falling.cpp
@@ -0,0 +1,57 @@
+#include <gtest/gtest.h>
+#include <time.h>
+#include <wiringPi.h>
+
+#define TRIGGER_PIN  0  // BCM 17
+#define LISTENER_PIN 1  // BCM 18
+
+/**
+ * Tests ISR for falling edges.
+ */
+class ISRFalling : public ::testing::Test {
+ public:
+  static void SetUpTestSuite() {
+    wiringPiSetup();
+    pinMode(TRIGGER_PIN, OUTPUT);
+    digitalWrite(TRIGGER_PIN, HIGH);
+    wiringPiISR(LISTENER_PIN, INT_EDGE_FALLING, ISRFalling::TriggerCount);
+    delay(100);
+  }
+
+  static void TearDownTestSuite() { digitalWrite(TRIGGER_PIN, LOW); }
+
+  static uint32_t count;
+  static void TriggerCount() { ++count; }
+
+ protected:
+  virtual void SetUp() { count = 0; }
+
+  virtual void TearDown() {
+    digitalWrite(TRIGGER_PIN, HIGH);
+    delay(10);
+  }
+};
+
+uint32_t ISRFalling::count = 0;
+
+TEST_F(ISRFalling, Fundamental) {
+  EXPECT_EQ(count, 0u);
+  digitalWrite(TRIGGER_PIN, LOW);
+  delay(10);
+  EXPECT_EQ(count, 1u);
+  digitalWrite(TRIGGER_PIN, HIGH);
+  delay(10);
+  EXPECT_EQ(count, 1u);
+}
+
+TEST_F(ISRFalling, ThreeTriggers) {
+  digitalWrite(TRIGGER_PIN, LOW);
+  delay(10);
+  count = 0;
+  for (int i = 0; i < 6; ++i) {
+    delay(10);
+    digitalWrite(TRIGGER_PIN, (i + 1) % 2);
+  }
+  delay(10);
+  EXPECT_EQ(count, 3u);
+}
\ No newline at end of file
diff --git a/wiringPi/gtest/test_isr_restart.cpp b/wiringPi/gtest/test_isr_restart.cpp
new file mode 100644
index 0000000..29c2f79
--- /dev/null
+++ b/wiringPi/gtest/test_isr_restart.cpp
@@ -0,0 +1,68 @@
+#include <gtest/gtest.h>
+#include <time.h>
+#include <wiringPi.h>
+
+#define TRIGGER_PIN  0  // BCM 17
+#define LISTENER_PIN 1  // BCM 18
+#define ANOTHER_LISTENER_PIN 6  // BCM 25
+
+/**
+ * Tests restarting ISR.
+ */
+class ISRRestart : public ::testing::Test {
+ public:
+  static void SetUpTestSuite() {
+    wiringPiSetup();
+    pinMode(TRIGGER_PIN, OUTPUT);
+    digitalWrite(TRIGGER_PIN, LOW);
+    wiringPiISR(LISTENER_PIN, INT_EDGE_RISING, ISRRestart::TriggerCount);
+    delay(100);
+  }
+
+  static uint32_t count;
+
+  static void TriggerCount() { ++count; }
+
+  static void TriggerCountDown() { --count; }
+
+ protected:
+  virtual void SetUp() { count = 0; }
+
+  virtual void TearDown() {
+    digitalWrite(TRIGGER_PIN, LOW);
+    delay(10);
+  }
+};
+
+uint32_t ISRRestart::count = 0;
+
+TEST_F(ISRRestart, RestartISR) {
+  // fundamental ISR test
+  EXPECT_EQ(count, 0u);
+  digitalWrite(TRIGGER_PIN, HIGH);
+  delay(10);
+  EXPECT_EQ(count, 1u);
+  digitalWrite(TRIGGER_PIN, LOW);
+  delay(10);
+  EXPECT_EQ(count, 1u);
+
+  // stop the ISR
+  EXPECT_EQ(wiringPiISRStop(LISTENER_PIN), 0);
+  digitalWrite(TRIGGER_PIN, HIGH);
+  delay(10);
+  EXPECT_EQ(count, 1u);
+  digitalWrite(TRIGGER_PIN, LOW);
+
+  // start another ISR on the same pin
+  EXPECT_EQ(
+      wiringPiISR(LISTENER_PIN, INT_EDGE_FALLING, ISRRestart::TriggerCountDown),
+      0);
+  count=1;
+  delay(100);
+  digitalWrite(TRIGGER_PIN, HIGH);
+  delay(10);
+  EXPECT_EQ(count, 1u);
+  digitalWrite(TRIGGER_PIN, LOW);
+  delay(10);
+  EXPECT_EQ(count, 0u);
+}
diff --git a/wiringPi/gtest/test_isr_restart2.cpp b/wiringPi/gtest/test_isr_restart2.cpp
new file mode 100644
index 0000000..df2ca5e
--- /dev/null
+++ b/wiringPi/gtest/test_isr_restart2.cpp
@@ -0,0 +1,109 @@
+#include <gtest/gtest.h>
+#include <time.h>
+#include <wiringPi.h>
+
+#define TRIGGER_PIN  0  // BCM 17
+#define LISTENER_PIN 1  // BCM 18
+#define ANOTHER_LISTENER_PIN 26  // BCM 12
+
+struct counters {
+  int32_t *primary;
+  int32_t *secondary;
+};
+
+/**
+ * Tests restarting ISR using function wiringPiISR2().
+ */
+class ISRRestart2 : public ::testing::Test {
+ public:
+  static void SetUpTestSuite() {
+    wiringPiSetup();
+    pinMode(TRIGGER_PIN, OUTPUT);
+    digitalWrite(TRIGGER_PIN, LOW);
+    counters_a.primary = &count;
+    counters_a.secondary = &count2;
+    counters_b.primary = &count;
+    counters_b.secondary = &count3;
+    wiringPiISR2(LISTENER_PIN, INT_EDGE_RISING, ISRRestart2::TriggerCount, 1000,
+                 &counters_a);
+    delay(100);
+  }
+
+  static int32_t count;
+  static int32_t count2;
+  static int32_t count3;
+
+  static counters counters_a;
+  static counters counters_b;
+
+  static void TriggerCount(WPIWfiStatus, void *userdata) {
+    struct counters *counters = (struct counters *)userdata;
+    ++*counters->primary;
+    ++*counters->secondary;
+  }
+
+  static void TriggerCountDown(WPIWfiStatus, void *userdata) {
+    struct counters *counters = (struct counters *)userdata;
+    ++*counters->primary;
+    --*counters->secondary;
+  }
+
+ protected:
+  virtual void SetUp() {
+    count = 0;
+    count2 = 0;
+    count3 = 0;
+  }
+
+  virtual void TearDown() {
+    digitalWrite(TRIGGER_PIN, LOW);
+    delay(10);
+  }
+};
+
+int32_t ISRRestart2::count = 0;
+int32_t ISRRestart2::count2 = 0;
+int32_t ISRRestart2::count3 = 0;
+struct counters ISRRestart2::counters_a;
+struct counters ISRRestart2::counters_b;
+
+TEST_F(ISRRestart2, RestartISR2) {
+  // fundamental ISR2 test
+  EXPECT_EQ(count, 0);
+  EXPECT_EQ(count2, 0);
+  digitalWrite(TRIGGER_PIN, HIGH);
+  delay(20);
+  EXPECT_EQ(count, 1);
+  EXPECT_EQ(count2, 1);
+  digitalWrite(TRIGGER_PIN, LOW);
+  delay(20);
+  EXPECT_EQ(count, 1);
+  EXPECT_EQ(count2, 1);
+
+  // stop the ISR
+  EXPECT_EQ(wiringPiISRStop(LISTENER_PIN), 0);
+  delay(100);
+  digitalWrite(TRIGGER_PIN, HIGH);
+  delay(20);
+  EXPECT_EQ(count, 1);
+  EXPECT_EQ(count2, 1);
+  EXPECT_EQ(count3, 0);
+  digitalWrite(TRIGGER_PIN, LOW);
+
+  // start another ISR2 on the same pin
+  EXPECT_EQ(wiringPiISR2(LISTENER_PIN, INT_EDGE_FALLING,
+                         ISRRestart2::TriggerCountDown, 0, &counters_b),
+            0);
+  delay(100);
+  digitalWrite(TRIGGER_PIN, HIGH);
+  delay(20);
+  EXPECT_EQ(count, 1);
+  EXPECT_EQ(count2, 1);
+  EXPECT_EQ(count3, 0);
+
+  digitalWrite(TRIGGER_PIN, LOW);
+  delay(20);
+  EXPECT_EQ(count, 2);
+  EXPECT_EQ(count2, 1);
+  EXPECT_EQ(count3, -1);
+}
diff --git a/wiringPi/gtest/test_isr_rising.cpp b/wiringPi/gtest/test_isr_rising.cpp
new file mode 100644
index 0000000..ea5473c
--- /dev/null
+++ b/wiringPi/gtest/test_isr_rising.cpp
@@ -0,0 +1,80 @@
+#include <gtest/gtest.h>
+#include <time.h>
+#include <wiringPi.h>
+
+#define TRIGGER_PIN  0  // BCM 17
+#define LISTENER_PIN 1  // BCM 18
+#define ANOTHER_LISTENER_PIN 26  // BCM 12
+
+/**
+ * Tests ISR for rising edges.
+ */
+class ISRRising : public ::testing::Test {
+ public:
+  static void SetUpTestSuite() {
+    wiringPiSetup();
+    pinMode(TRIGGER_PIN, OUTPUT);
+    digitalWrite(TRIGGER_PIN, LOW);
+    wiringPiISR(LISTENER_PIN, INT_EDGE_RISING, ISRRising::TriggerCount);
+    delay(100);
+  }
+
+  static uint32_t count;
+
+  static void TriggerCount() { ++count; }
+
+  static void TriggerCountDown() { --count; }
+
+ protected:
+  virtual void SetUp() { count = 0; }
+
+  virtual void TearDown() {
+    digitalWrite(TRIGGER_PIN, LOW);
+    delay(10);
+  }
+};
+
+uint32_t ISRRising::count = 0;
+
+TEST_F(ISRRising, Fundamental) {
+  EXPECT_EQ(count, 0u);
+  digitalWrite(TRIGGER_PIN, HIGH);
+  delay(10);
+  EXPECT_EQ(count, 1u);
+  digitalWrite(TRIGGER_PIN, LOW);
+  delay(10);
+  EXPECT_EQ(count, 1u);
+}
+
+TEST_F(ISRRising, ThreeTriggers) {
+  digitalWrite(TRIGGER_PIN, HIGH);
+  delay(10);
+  count = 0;
+  for (int i = 0; i < 6; ++i) {
+    delay(10);
+    digitalWrite(TRIGGER_PIN, i % 2);
+  }
+  delay(10);
+  EXPECT_EQ(count, 3u);
+}
+
+TEST_F(ISRRising, ISRInitConflict) {
+  // this initialization should fail for ISR conflict
+  EXPECT_EQ(
+      wiringPiISR(LISTENER_PIN, INT_EDGE_FALLING, ISRRising::TriggerCountDown),
+      -1);
+  // ensure the initialization above has released the mutex lock
+  EXPECT_EQ(wiringPiISR(ANOTHER_LISTENER_PIN, INT_EDGE_RISING,
+                        ISRRising::TriggerCountDown),
+            0);
+  delay(100);
+
+  // ensure the existing ISR has not broken
+  EXPECT_EQ(count, 0u);
+  digitalWrite(TRIGGER_PIN, HIGH);
+  delay(10);
+  EXPECT_EQ(count, 1u);
+  digitalWrite(TRIGGER_PIN, LOW);
+  delay(10);
+  EXPECT_EQ(count, 1u);
+}
diff --git a/wiringPi/gtest/test_isr_rising2.cpp b/wiringPi/gtest/test_isr_rising2.cpp
new file mode 100644
index 0000000..19261ad
--- /dev/null
+++ b/wiringPi/gtest/test_isr_rising2.cpp
@@ -0,0 +1,135 @@
+#include <gtest/gtest.h>
+#include <time.h>
+#include <wiringPi.h>
+
+#define TRIGGER_PIN  0  // BCM 17
+#define LISTENER_PIN 1  // BCM 18
+#define ANOTHER_LISTENER_PIN 26  // BCM 12
+
+struct counters {
+  uint32_t *primary;
+  uint32_t *secondary;
+};
+
+/**
+ * Tests ISR for rising edges.
+ * Function wiringPiISR2 is used for the configuraiton.
+ */
+class ISRRising2 : public ::testing::Test {
+ public:
+  static void SetUpTestSuite() {
+    wiringPiSetup();
+    pinMode(TRIGGER_PIN, OUTPUT);
+    digitalWrite(TRIGGER_PIN, LOW);
+    counters_a.primary = &count;
+    counters_a.secondary = &count2;
+    counters_b.primary = &count;
+    counters_b.secondary = &count3;
+    wiringPiISR2(LISTENER_PIN, INT_EDGE_RISING, ISRRising2::TriggerCount, 1000,
+                 &counters_a);
+    delay(100);
+  }
+
+  static uint32_t count;
+  static uint32_t count2;
+  static uint32_t count3;
+
+  static counters counters_a;
+  static counters counters_b;
+
+  static void TriggerCount(WPIWfiStatus, void *userdata) {
+    struct counters *counters = (struct counters *)userdata;
+    ++*counters->primary;
+    ++*counters->secondary;
+  }
+
+  static void TriggerCountDown(WPIWfiStatus, void *userdata) {
+    struct counters *counters = (struct counters *)userdata;
+    ++*counters->primary;
+    --*counters->secondary;
+  }
+
+ protected:
+  virtual void SetUp() {
+    count = 0;
+    count2 = 0;
+    count3 = 0;
+  }
+
+  virtual void TearDown() {
+    digitalWrite(TRIGGER_PIN, LOW);
+    delay(10);
+  }
+};
+
+uint32_t ISRRising2::count = 0;
+uint32_t ISRRising2::count2 = 0;
+uint32_t ISRRising2::count3 = 0;
+struct counters ISRRising2::counters_a;
+struct counters ISRRising2::counters_b;
+
+TEST_F(ISRRising2, Fundamental) {
+  EXPECT_EQ(count, 0u);
+  EXPECT_EQ(count2, 0u);
+  digitalWrite(TRIGGER_PIN, HIGH);
+  delay(20);
+  EXPECT_EQ(count, 1u);
+  EXPECT_EQ(count2, 1u);
+  digitalWrite(TRIGGER_PIN, LOW);
+  delay(20);
+  EXPECT_EQ(count, 1u);
+  EXPECT_EQ(count2, 1u);
+}
+
+TEST_F(ISRRising2, ThreeTriggers) {
+  digitalWrite(TRIGGER_PIN, HIGH);
+  delay(10);
+  count = 0;
+  for (int i = 0; i < 6; ++i) {
+    digitalWrite(TRIGGER_PIN, i % 2);
+    delay(20);
+  }
+  EXPECT_EQ(count, 3u);
+}
+
+TEST_F(ISRRising2, Debounce) {
+  delay(20);
+  for (int i = 0; i < 7; ++i) {
+    digitalWrite(TRIGGER_PIN, (i + 1) % 2);
+  }
+  delay(20);
+  EXPECT_EQ(count, 1u);
+}
+
+TEST_F(ISRRising2, ISRInitConflict) {
+  // this initialization should fail for ISR conflict
+  EXPECT_EQ(wiringPiISR2(LISTENER_PIN, INT_EDGE_FALLING,
+                         ISRRising2::TriggerCountDown, 0, &counters_b),
+            -1);
+  // ensure the initialization above has released the mutex lock
+  EXPECT_EQ(wiringPiISR2(ANOTHER_LISTENER_PIN, INT_EDGE_BOTH,
+                         ISRRising2::TriggerCountDown, 0, &counters_b),
+            0);
+  delay(100);
+
+  // ensure the existing ISR has not broken
+  EXPECT_EQ(count, 0u);
+  EXPECT_EQ(count2, 0u);
+  digitalWrite(TRIGGER_PIN, HIGH);
+  delay(20);
+  EXPECT_EQ(count, 1u);
+  EXPECT_EQ(count2, 1u);
+  digitalWrite(TRIGGER_PIN, LOW);
+  delay(20);
+  EXPECT_EQ(count, 1u);
+  EXPECT_EQ(count2, 1u);
+
+  delay(20);
+  count = 0;
+  for (int i = 0; i < 7; ++i) {
+    delay(1);
+    digitalWrite(TRIGGER_PIN, (i + 1) % 2);
+  }
+  delay(20);
+  EXPECT_EQ(count, 1u);
+}
diff --git a/wiringPi/htu21d.c b/wiringPi/htu21d.c
index 11f20eb..1fde612 100644
--- a/wiringPi/htu21d.c
+++ b/wiringPi/htu21d.c
@@ -25,6 +25,7 @@
 
 #include <unistd.h>
 #include <stdint.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <math.h>
 
@@ -40,7 +41,7 @@
 
 int checksum (UNU uint8_t data [4])
 {
-  return TRUE ;
+  return true ;
 }
 
 
@@ -127,7 +128,7 @@ int htu21dSetup (const int pinBase)
   int status ;
 
   if ((fd = wiringPiI2CSetup (I2C_ADDRESS)) < 0)
-    return FALSE ;
+    return false ;
 
   node = wiringPiNewNode (pinBase, 2) ;
 
@@ -138,7 +139,7 @@ int htu21dSetup (const int pinBase)
 
   data = 0xFE ;
   if (write (fd, &data, 1) != 1)
-    return FALSE ;
+    return false ;
 
   delay (15) ;
 
@@ -146,5 +147,5 @@ int htu21dSetup (const int pinBase)
 
   status = wiringPiI2CReadReg8 (fd, 0xE7) ;
 
-  return (status == 0x02) ? TRUE : FALSE ;
+  return (status == 0x02) ? true : false ;
 }
diff --git a/wiringPi/max31855.c b/wiringPi/max31855.c
index 46fe74d..54e19bd 100644
--- a/wiringPi/max31855.c
+++ b/wiringPi/max31855.c
@@ -24,6 +24,7 @@
 
 #include <byteswap.h>
 #include <stdint.h>
+#include <stdbool.h>
 
 #include <wiringPi.h>
 #include <wiringPiSPI.h>
@@ -88,12 +89,12 @@ int max31855Setup (const int pinBase, int spiChannel)
   struct wiringPiNodeStruct *node ;
 
   if (wiringPiSPISetup (spiChannel, 5000000) < 0)	// 5MHz - prob 4 on the Pi
-    return FALSE ;
+    return false ;
 
   node = wiringPiNewNode (pinBase, 4) ;
 
   node->fd         = spiChannel ;
   node->analogRead = myAnalogRead ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/max5322.c b/wiringPi/max5322.c
index 888b01a..a8f4810 100644
--- a/wiringPi/max5322.c
+++ b/wiringPi/max5322.c
@@ -22,6 +22,8 @@
  ***********************************************************************
  */
 
+#include <stdbool.h>
+
 #include <wiringPi.h>
 #include <wiringPiSPI.h>
 
@@ -66,7 +68,7 @@ int max5322Setup (const int pinBase, int spiChannel)
   unsigned char spiData [2] ;
 
   if (wiringPiSPISetup (spiChannel, 8000000) < 0)	// 10MHz Max
-    return FALSE ;
+    return false ;
 
   node = wiringPiNewNode (pinBase, 2) ;
 
@@ -80,5 +82,5 @@ int max5322Setup (const int pinBase, int spiChannel)
   
   wiringPiSPIDataRW (node->fd, spiData, 2) ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/mcp23008.c b/wiringPi/mcp23008.c
index bff6f49..22e5a5d 100644
--- a/wiringPi/mcp23008.c
+++ b/wiringPi/mcp23008.c
@@ -23,6 +23,7 @@
  */
 
 #include <stdio.h>
+#include <stdbool.h>
 #include <pthread.h>
 
 #include "wiringPi.h"
@@ -132,7 +133,7 @@ int mcp23008Setup (const int pinBase, const int i2cAddress)
   struct wiringPiNodeStruct *node ;
 
   if ((fd = wiringPiI2CSetup (i2cAddress)) < 0)
-    return FALSE ;
+    return false ;
 
   wiringPiI2CWriteReg8 (fd, MCP23x08_IOCON, IOCON_INIT) ;
 
@@ -145,5 +146,5 @@ int mcp23008Setup (const int pinBase, const int i2cAddress)
   node->digitalWrite    = myDigitalWrite ;
   node->data2           = wiringPiI2CReadReg8 (fd, MCP23x08_OLAT) ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/mcp23016.c b/wiringPi/mcp23016.c
index b4669ba..4726967 100644
--- a/wiringPi/mcp23016.c
+++ b/wiringPi/mcp23016.c
@@ -23,6 +23,7 @@
  */
 
 #include <stdio.h>
+#include <stdbool.h>
 #include <pthread.h>
 
 #include "wiringPi.h"
@@ -146,7 +147,7 @@ int mcp23016Setup (const int pinBase, const int i2cAddress)
   struct wiringPiNodeStruct *node ;
 
   if ((fd = wiringPiI2CSetup (i2cAddress)) < 0)
-    return FALSE ;
+    return false ;
 
   wiringPiI2CWriteReg8 (fd, MCP23016_IOCON0, IOCON_INIT) ;
   wiringPiI2CWriteReg8 (fd, MCP23016_IOCON1, IOCON_INIT) ;
@@ -160,5 +161,5 @@ int mcp23016Setup (const int pinBase, const int i2cAddress)
   node->data2           = wiringPiI2CReadReg8 (fd, MCP23016_OLAT0) ;
   node->data3           = wiringPiI2CReadReg8 (fd, MCP23016_OLAT1) ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/mcp23017.c b/wiringPi/mcp23017.c
index eedf059..da45fb0 100644
--- a/wiringPi/mcp23017.c
+++ b/wiringPi/mcp23017.c
@@ -23,6 +23,7 @@
  */
 
 #include <stdio.h>
+#include <stdbool.h>
 #include <pthread.h>
 
 #include "wiringPi.h"
@@ -177,7 +178,7 @@ int mcp23017Setup (const int pinBase, const int i2cAddress)
   struct wiringPiNodeStruct *node ;
 
   if ((fd = wiringPiI2CSetup (i2cAddress)) < 0)
-    return FALSE ;
+    return false ;
 
   wiringPiI2CWriteReg8 (fd, MCP23x17_IOCON, IOCON_INIT) ;
 
@@ -191,5 +192,5 @@ int mcp23017Setup (const int pinBase, const int i2cAddress)
   node->data2           = wiringPiI2CReadReg8 (fd, MCP23x17_OLATA) ;
   node->data3           = wiringPiI2CReadReg8 (fd, MCP23x17_OLATB) ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/mcp23s08.c b/wiringPi/mcp23s08.c
index d9dbee7..a44733e 100644
--- a/wiringPi/mcp23s08.c
+++ b/wiringPi/mcp23s08.c
@@ -24,6 +24,7 @@
 
 #include <stdio.h>
 #include <stdint.h>
+#include <stdbool.h>
 
 #include "wiringPi.h"
 #include "wiringPiSPI.h"
@@ -170,7 +171,7 @@ int mcp23s08Setup (const int pinBase, const int spiPort, const int devId)
   struct wiringPiNodeStruct *node ;
 
   if (wiringPiSPISetup (spiPort, MCP_SPEED) < 0)
-    return FALSE ;
+    return false ;
 
   writeByte (spiPort, devId, MCP23x08_IOCON, IOCON_INIT) ;
 
@@ -184,5 +185,5 @@ int mcp23s08Setup (const int pinBase, const int spiPort, const int devId)
   node->digitalWrite    = myDigitalWrite ;
   node->data2           = readByte (spiPort, devId, MCP23x08_OLAT) ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/mcp23s17.c b/wiringPi/mcp23s17.c
index daf7f40..56117f5 100644
--- a/wiringPi/mcp23s17.c
+++ b/wiringPi/mcp23s17.c
@@ -24,6 +24,7 @@
 
 #include <stdio.h>
 #include <stdint.h>
+#include <stdbool.h>
 
 #include "wiringPi.h"
 #include "wiringPiSPI.h"
@@ -215,7 +216,7 @@ int mcp23s17Setup (const int pinBase, const int spiPort, const int devId)
   struct wiringPiNodeStruct *node ;
 
   if (wiringPiSPISetup (spiPort, MCP_SPEED) < 0)
-    return FALSE ;
+    return false ;
 
   writeByte (spiPort, devId, MCP23x17_IOCON,  IOCON_INIT | IOCON_HAEN) ;
   writeByte (spiPort, devId, MCP23x17_IOCONB, IOCON_INIT | IOCON_HAEN) ;
@@ -231,5 +232,5 @@ int mcp23s17Setup (const int pinBase, const int spiPort, const int devId)
   node->data2           = readByte (spiPort, devId, MCP23x17_OLATA) ;
   node->data3           = readByte (spiPort, devId, MCP23x17_OLATB) ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/mcp3002.c b/wiringPi/mcp3002.c
index 04ce10a..c890053 100644
--- a/wiringPi/mcp3002.c
+++ b/wiringPi/mcp3002.c
@@ -22,6 +22,8 @@
  ***********************************************************************
  */
 
+#include <stdbool.h>
+
 #include <wiringPi.h>
 #include <wiringPiSPI.h>
 
@@ -65,12 +67,12 @@ int mcp3002Setup (const int pinBase, int spiChannel)
   struct wiringPiNodeStruct *node ;
 
   if (wiringPiSPISetup (spiChannel, 1000000) < 0)
-    return FALSE ;
+    return false ;
 
   node = wiringPiNewNode (pinBase, 2) ;
 
   node->fd         = spiChannel ;
   node->analogRead = myAnalogRead ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/mcp3004.c b/wiringPi/mcp3004.c
index 0bfc8a7..3cca2bd 100644
--- a/wiringPi/mcp3004.c
+++ b/wiringPi/mcp3004.c
@@ -24,6 +24,8 @@
  ***********************************************************************
  */
 
+#include <stdbool.h>
+
 #include <wiringPi.h>
 #include <wiringPiSPI.h>
 
@@ -65,12 +67,12 @@ int mcp3004Setup (const int pinBase, int spiChannel)
   struct wiringPiNodeStruct *node ;
 
   if (wiringPiSPISetup (spiChannel, 1000000) < 0)
-    return FALSE ;
+    return false ;
 
   node = wiringPiNewNode (pinBase, 8) ;
 
   node->fd         = spiChannel ;
   node->analogRead = myAnalogRead ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/mcp3422.c b/wiringPi/mcp3422.c
index fd441a5..0057dd4 100644
--- a/wiringPi/mcp3422.c
+++ b/wiringPi/mcp3422.c
@@ -28,6 +28,7 @@
 #include <stdio.h>
 #include <unistd.h>
 #include <stdint.h>
+#include <stdbool.h>
 #include <fcntl.h>
 #include <sys/ioctl.h>
 
@@ -117,7 +118,7 @@ int mcp3422Setup (int pinBase, int i2cAddress, int sampleRate, int gain)
   struct wiringPiNodeStruct *node ;
 
   if ((fd = wiringPiI2CSetup (i2cAddress)) < 0)
-    return FALSE ;
+    return false ;
 
   node = wiringPiNewNode (pinBase, 4) ;
 
@@ -126,5 +127,5 @@ int mcp3422Setup (int pinBase, int i2cAddress, int sampleRate, int gain)
   node->data1      = gain ;
   node->analogRead = myAnalogRead ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/mcp4802.c b/wiringPi/mcp4802.c
index 4a411eb..ac65de9 100644
--- a/wiringPi/mcp4802.c
+++ b/wiringPi/mcp4802.c
@@ -22,6 +22,8 @@
  ***********************************************************************
  */
 
+#include <stdbool.h>
+
 #include <wiringPi.h>
 #include <wiringPiSPI.h>
 
@@ -65,12 +67,12 @@ int mcp4802Setup (const int pinBase, int spiChannel)
   struct wiringPiNodeStruct *node ;
 
   if (wiringPiSPISetup (spiChannel, 1000000) < 0)
-    return FALSE ;
+    return false ;
 
   node = wiringPiNewNode (pinBase, 2) ;
 
   node->fd          = spiChannel ;
   node->analogWrite = myAnalogWrite ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/pcf8574.c b/wiringPi/pcf8574.c
index 61b4cc7..b40fbe9 100644
--- a/wiringPi/pcf8574.c
+++ b/wiringPi/pcf8574.c
@@ -23,6 +23,7 @@
  */
 
 #include <stdio.h>
+#include <stdbool.h>
 #include <pthread.h>
 
 #include "wiringPi.h"
@@ -113,7 +114,7 @@ int pcf8574Setup (const int pinBase, const int i2cAddress)
   struct wiringPiNodeStruct *node ;
 
   if ((fd = wiringPiI2CSetup (i2cAddress)) < 0)
-    return FALSE ;
+    return false ;
 
   node = wiringPiNewNode (pinBase, 8) ;
 
@@ -123,5 +124,5 @@ int pcf8574Setup (const int pinBase, const int i2cAddress)
   node->digitalWrite = myDigitalWrite ;
   node->data2        = wiringPiI2CRead (fd) ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/pcf8591.c b/wiringPi/pcf8591.c
index 10beb6b..0ad812d 100644
--- a/wiringPi/pcf8591.c
+++ b/wiringPi/pcf8591.c
@@ -24,6 +24,7 @@
  */
 
 #include <unistd.h>
+#include <stdbool.h>
 #include <stdio.h>
 
 #include "wiringPi.h"
@@ -82,7 +83,7 @@ int pcf8591Setup (const int pinBase, const int i2cAddress)
   struct wiringPiNodeStruct *node ;
 
   if ((fd = wiringPiI2CSetup (i2cAddress)) < 0)
-    return FALSE ;
+    return false ;
 
   node = wiringPiNewNode (pinBase, 4) ;
 
@@ -90,5 +91,5 @@ int pcf8591Setup (const int pinBase, const int i2cAddress)
   node->analogRead  = myAnalogRead ;
   node->analogWrite = myAnalogWrite ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/pseudoPins.c b/wiringPi/pseudoPins.c
index c162457..e41a5ab 100644
--- a/wiringPi/pseudoPins.c
+++ b/wiringPi/pseudoPins.c
@@ -41,6 +41,7 @@
 #include <sys/mman.h>
 #include <fcntl.h>
 #include <stdint.h>
+#include <stdbool.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 
@@ -80,24 +81,24 @@ int pseudoPinsSetup(const int pinBase)
     node = wiringPiNewNode(pinBase, PSEUDO_PINS);
     if (node == NULL) {
       fprintf(stderr, "Error creating new wiringPi node");
-      return FALSE;
+      return false;
     }
 
     node->fd = shm_open(SHARED_NAME, O_CREAT | O_RDWR, 0666);
     if (node->fd < 0) {
       perror("Error opening shared memory");
-      return FALSE;
+      return false;
     }
 
     if (ftruncate(node->fd, PSEUDO_PINS * sizeof(int)) < 0) {
       perror("Error resizing shared memory");
-      return FALSE;
+      return false;
     }
 
     ptr = mmap(NULL, PSEUDO_PINS * sizeof(int), PROT_READ | PROT_WRITE, MAP_SHARED, node->fd, 0);
     if (ptr == MAP_FAILED) {
       perror("Error mapping shared memory");
-      return FALSE;
+      return false;
     }
 
     node->data0 = (unsigned int)(uintptr_t)ptr;
@@ -105,5 +106,5 @@ int pseudoPinsSetup(const int pinBase)
     node->analogRead = myAnalogRead;
     node->analogWrite = myAnalogWrite;
 
-    return TRUE;
+    return true;
 }
diff --git a/wiringPi/rht03.c b/wiringPi/rht03.c
index 25d844f..99461b6 100644
--- a/wiringPi/rht03.c
+++ b/wiringPi/rht03.c
@@ -25,6 +25,7 @@
 #include <sys/time.h>
 #include <stdio.h>
 #include <stdio.h>
+#include <stdbool.h>
 #include <time.h>
 
 #include "wiringPi.h"
@@ -51,7 +52,7 @@ static int maxDetectLowHighWait (const int pin)
   {
     gettimeofday (&now, NULL) ;
     if (timercmp (&now, &timeUp, >))
-      return FALSE ;
+      return false ;
   }
 
 // Wait for it to go HIGH
@@ -65,10 +66,10 @@ static int maxDetectLowHighWait (const int pin)
   {
     gettimeofday (&now, NULL) ;
     if (timercmp (&now, &timeUp, >))
-      return FALSE ;
+      return false ;
   }
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -103,7 +104,7 @@ static unsigned int maxDetectClockByte (const int pin)
 /*
  * maxDetectRead:
  *	Read in and return the 4 data bytes from the MaxDetect sensor.
- *	Return TRUE/FALSE depending on the checksum validity
+ *	Return true/false depending on the checksum validity
  *********************************************************************************
  */
 
@@ -129,7 +130,7 @@ static int maxDetectRead (const int pin, unsigned char buffer [4])
 // Now wait for sensor to pull pin low
 
   if (!maxDetectLowHighWait (pin))
-    return FALSE ;
+    return false ;
 
 // and read in 5 bytes (40 bits)
 
@@ -158,7 +159,7 @@ static int maxDetectRead (const int pin, unsigned char buffer [4])
 // reading is probably bogus.
 
   if ((took.tv_sec != 0) || (took.tv_usec > 16000))
-    return FALSE ;
+    return false ;
 
   return checksum == localBuf [4] ;
 }
@@ -181,7 +182,7 @@ static int myReadRHT03 (const int pin, int *temp, int *rh)
   result = maxDetectRead (pin, buffer) ;
 
   if (!result)
-    return FALSE ;
+    return false ;
 
   *rh   = (buffer [0] * 256 + buffer [1]) ;
   *temp = (buffer [2] * 256 + buffer [3]) ;
@@ -196,9 +197,9 @@ static int myReadRHT03 (const int pin, int *temp, int *rh)
 //	(which does seem to happen - no realtime here)
 
   if ((*rh > 999) || (*temp > 800) || (*temp < -400))
-    return FALSE ;
+    return false ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -239,7 +240,7 @@ int rht03Setup (const int pinBase, const int piPin)
   struct wiringPiNodeStruct *node ;
 
   if ((piPin & PI_GPIO_MASK) != 0)	// Must be an on-board pin
-    return FALSE ;
+    return false ;
   
 // 2 pins - temperature and humidity
 
@@ -248,5 +249,5 @@ int rht03Setup (const int pinBase, const int piPin)
   node->fd         = piPin ;
   node->analogRead = myAnalogRead ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/sn3218.c b/wiringPi/sn3218.c
index 1302286..9b4ba2c 100644
--- a/wiringPi/sn3218.c
+++ b/wiringPi/sn3218.c
@@ -22,6 +22,8 @@
  ***********************************************************************
  */
 
+#include <stdbool.h>
+
 #include <wiringPi.h>
 #include <wiringPiI2C.h>
 
@@ -55,7 +57,7 @@ int sn3218Setup (const int pinBase)
   struct wiringPiNodeStruct *node ;
 
   if ((fd = wiringPiI2CSetup (0x54)) < 0)
-    return FALSE ;
+    return false ;
 
 // Setup the chip - initialise all 18 LEDs to off
 
@@ -71,5 +73,5 @@ int sn3218Setup (const int pinBase)
   node->fd          = fd ;
   node->analogWrite = myAnalogWrite ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/sr595.c b/wiringPi/sr595.c
index b42e583..384785e 100644
--- a/wiringPi/sr595.c
+++ b/wiringPi/sr595.c
@@ -29,6 +29,7 @@
 
 #include <stdio.h>
 #include <stdint.h>
+#include <stdbool.h>
 
 #include "wiringPi.h"
 
@@ -105,5 +106,5 @@ int sr595Setup (const int pinBase, const int numPins,
   pinMode (clockPin, OUTPUT) ;
   pinMode (latchPin, OUTPUT) ;
 
-  return TRUE ;
+  return true ;
 }
diff --git a/wiringPi/test/wiringpi_test7_bench.c b/wiringPi/test/wiringpi_test7_bench.c
index 9c0f221..ffdf367 100644
--- a/wiringPi/test/wiringpi_test7_bench.c
+++ b/wiringPi/test/wiringpi_test7_bench.c
@@ -83,7 +83,8 @@ int main (void) {
     case PI_MODEL_400:
     case PI_MODEL_CM4:
     case PI_MODEL_CM4S:
-      fExpectTimedigitalWrite = 0.020; //us
+      //fExpectTimedigitalWrite = 0.020; //us  - with kernel <6.12.47
+      fExpectTimedigitalWrite = 0.016; //us
       fExpectTimedigitalRead  = 0.038; //us
       fExpectTimepinMode      = 0.121; //us
       fWriteReadDelayFactor   = 1.86;
diff --git a/wiringPi/test/wiringpi_test9_pwm.c b/wiringPi/test/wiringpi_test9_pwm.c
index 88775fc..ee6da97 100644
--- a/wiringPi/test/wiringpi_test9_pwm.c
+++ b/wiringPi/test/wiringpi_test9_pwm.c
@@ -77,15 +77,18 @@ int main (void) {
     int Pi5 = 0;
     double MaxFreq = 100.0;
     switch(RaspberryPiModel) {
-      case PI_MODEL_A:
+     case PI_MODEL_A:
       case PI_MODEL_B:
       case PI_MODEL_BP:
       case PI_MODEL_AP:
+      case PI_MODEL_CM:
+        MaxFreq = 5.0; // 4.8 kHz -> ~26% CPU@800 MHz
+        printf(" - Pi1/BCM2835 detected, will skip tests with frequency above %g kHz\n", MaxFreq);
+        break;
       case PI_MODEL_ZERO:
       case PI_MODEL_ZERO_W:
-      case PI_MODEL_CM:
-        MaxFreq = 13.0; // 12.5 kHz -> ~40% CPU@800 MHz
-        printf(" - Pi1/BCM2835 detected, will skip tests with frequency above %g kHz\n", MaxFreq);
+        MaxFreq = 13.0; // 12.5 kHz -> ~42% CPU@1000 MHz
+        printf(" - PiZero/BCM2835 detected, will skip tests with frequency above %g kHz\n", MaxFreq);
         break;
       case PI_MODEL_2:
         MaxFreq = 20.0;
diff --git a/wiringPi/test/wiringpi_xotest_test1_spi.c b/wiringPi/test/wiringpi_xotest_test1_spi.c
index 80ca562..c570864 100644
--- a/wiringPi/test/wiringpi_xotest_test1_spi.c
+++ b/wiringPi/test/wiringpi_xotest_test1_spi.c
@@ -1,15 +1,14 @@
-// WiringPi test program: SPI functions (need XO hardware)
+// WiringPi test program: SPI functions (need XO hardware)
 // Compile: gcc -Wall wiringpi_xotest_test1_spi.c -o wiringpi_xotest_test1_spi -lwiringPi
 
 #include <unistd.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <signal.h>
 #include <time.h>
 #include "wpi_test.h"
 #include <wiringPiSPI.h>
 
-#define TRUE                (1==1)
-#define FALSE               (!TRUE)
 #define CHAN_CONFIG_SINGLE  8
 #define CHAN_CONFIG_DIFF    0
 
@@ -66,17 +65,19 @@ int main(int argc, char *argv []){
 
     wiringPiSetup();
 
-    if ((hSPI = wiringPiSPISetup (spiChannel, spiSpeed)) < 0) {
+        printf("wiringPiSPISetup (spiChannel=%d, spiSpeed=%d)\n",spiChannel, spiSpeed);
+    if ((hSPI = wiringPiSPISetup(spiChannel, spiSpeed)) < 0) {
         FailAndExitWithErrno("wiringPiSPISetup", hSPI);
     }
 
     int hSPIOld=hSPI;
-    //printf("\nSPI fd = %d\n call close now\n", hSPI);
+      printf("wiringPiSPIClose(spiChannel=%d)\n",spiChannel);
     int ret = wiringPiSPIClose(spiChannel);
     if (ret!=0) {
         FailAndExitWithErrno("wiringPiSPIClose", ret);
     }
 
+        printf("wiringPiSPIxSetupMode(0, spiChannel=%d, spiSpeed=%d, 0)\n",spiChannel, spiSpeed);
     if ((hSPI = wiringPiSPIxSetupMode(0, spiChannel, spiSpeed, 0)) < 0) {
         FailAndExitWithErrno("wiringPiSPIxSetup", hSPI);
     }
@@ -151,12 +152,18 @@ int main(int argc, char *argv []){
     digitalWriteEx(24, GPIOIn, HIGH);
     checkVoltage(3.3f, "Analog value  6xHigh");
 
-    CH1 = AnalogRead(3, 1, &returnvalue);
-    CheckSame("\nReading Wrong channel 3 result         ", CH1, 0);
-    CheckSame("\nReading Wrong channel 3 ioctl result   ", returnvalue, -EINVAL);
-    CH1 = AnalogRead(2, 1, &returnvalue);
-    CheckSame("\nReading Wrong channel 2 result         ", CH1, 0);
-    CheckSame("\nReading Wrong channel 3  ioctl result  ", returnvalue, -EBADF);
+
+    int unsupportedSPICh = 5;
+    printf("\nCheck error for unsupported channel %d\n", unsupportedSPICh);
+    CH1 = AnalogRead(unsupportedSPICh, 1, &returnvalue);
+    CheckSame("\nReading unsupported channel result         ", CH1, 0);
+    CheckSame("Reading unsupported channel ioctl result   ", returnvalue, -EINVAL);
+
+    int uninitSPICh = 2;
+    printf("\nCheck error for uninitialized channel %d\n", uninitSPICh);
+    CH1 = AnalogRead(uninitSPICh, 1, &returnvalue);
+    CheckSame("\nReading uninitialized channel result       ", CH1, 0);
+    CheckSame("Reading uninitialized channel ioctl result ", returnvalue, -EBADF);
 
     pinMode(22, INPUT);
     pinMode(21, INPUT);
@@ -165,6 +172,7 @@ int main(int argc, char *argv []){
     pinMode(27, INPUT);
     pinMode(28, INPUT);
 
+printf("\nwiringPiSPIxClose(0, spiChannel=%d)\n",spiChannel);
     ret = wiringPiSPIxClose(0, spiChannel);
     CheckSame("wiringPiSPIxClose result", ret, 0);
     if (ret!=0) {
@@ -175,4 +183,3 @@ int main(int argc, char *argv []){
 
     return UnitTestState();
 }
-
diff --git a/wiringPi/wiringPi.c b/wiringPi/wiringPi.c
index 5bbe5b3..d387d1a 100644
--- a/wiringPi/wiringPi.c
+++ b/wiringPi/wiringPi.c
@@ -1,7 +1,7 @@
 /*
  * wiringPi:
  *	Arduino look-a-like Wiring library for the Raspberry Pi
- *	Copyright (c) 2012-2025 Gordon Henderson and contributors
+ *	Copyright (c) 2012–2019 Gordon Henderson; 2019–2026 Contributors
  *	Additional code for pwmSetClock by Chris Hall <chris@kchall.plus.com>
  *
  *	Thanks to code samples from Gert Jan van Loo and the
@@ -55,6 +55,7 @@
 #include <stdio.h>
 #include <stdarg.h>
 #include <stdint.h>
+#include <stdbool.h>
 #include <stdlib.h>
 #include <stdbool.h>
 #include <ctype.h>
@@ -251,8 +252,8 @@ static volatile unsigned int GPIO_RIO ;
 #define	PAGE_SIZE		(4*1024)
 #define	BLOCK_SIZE		(4*1024)
 
-static unsigned int usingGpioMem    = FALSE ;
-static          int wiringPiSetuped = FALSE ;
+static unsigned int usingGpioMem    = false ;
+static          int wiringPiSetuped = false ;
 
 // PWM
 //	Word offsets into the PWM control region
@@ -447,12 +448,12 @@ static int RaspberryPiLayout = -1;
 
 // Debugging & Return codes
 
-int wiringPiDebug       = FALSE ;
-int wiringPiReturnCodes = FALSE ;
+int wiringPiDebug       = false ;
+int wiringPiReturnCodes = false ;
 
 // Use /dev/gpiomem ?
 
-int wiringPiTryGpioMem  = FALSE ;
+int wiringPiTryGpioMem  = false ;
 
 enum WPIFlag {
   WPI_FLAG_INPUT    = 0x04,
@@ -1688,7 +1689,7 @@ struct wiringPiNodeStruct *wiringPiNewNode (int pinBase, int numPins)
     if (wiringPiFindNode (pin) != NULL)
       (void)wiringPiFailure (WPI_FATAL, "wiringPiNewNode: Pin %d overlaps with existing definition\n", pin) ;
 
-  node = (struct wiringPiNodeStruct *)calloc (sizeof (struct wiringPiNodeStruct), 1) ;	// calloc zeros
+  node = (struct wiringPiNodeStruct *)calloc(1, sizeof (struct wiringPiNodeStruct));  // calloc zeros
   if (node == NULL)
     (void)wiringPiFailure (WPI_FATAL, "wiringPiNewNode: Unable to allocate memory: %s\n", strerror (errno)) ;
 
@@ -2299,10 +2300,10 @@ int digitalRead (int pin)
     }
 
     if (ISRP1MODEL) {
-      switch(gpio[2*pin] & RP1_STATUS_LEVEL_MASK) {
-        default: // 11 or 00 not allowed, give LOW!
-        case RP1_STATUS_LEVEL_LOW:  return LOW ;
-        case RP1_STATUS_LEVEL_HIGH: return HIGH ;
+      if ((gpio[2*pin] & RP1_STATUS_LEVEL_MASK) == RP1_STATUS_LEVEL_HIGH) {
+        return HIGH;
+      } else { // 11 or 00 not allowed, give LOW!
+        return LOW;
       }
     } else {
       if ((*(gpio + gpioToGPLEV [pin]) & (1 << (pin & 31))) != 0)
@@ -2867,42 +2868,32 @@ int waitForInterruptClose(int pin) {
 }
 
 /*
- * interruptHandlerV2:
- *	This is a thread and gets started to wait for the interrupt we're
- *	hoping to catch. It will call the user-function when the interrupt
- *	fires.
+ * interruptHandlerInit:
+ *	Initializes an interrupt handler before starting the listener loop in a
+ *	separate thread.
+ *	Returns: >0 on successful initialization, 0 if the listener loop does not
+ *	have to start, -1 on error.
  *********************************************************************************
  */
 
-void *interruptHandlerV2(void *arg)
+static int interruptHandlerInit(int pin, int EdgeMode, unsigned long debounce_period_us)
 {
-  const char* strmode = ""; 
-  int pin, EdgeMode, ret, fd, attr, i;
-  unsigned int readret;
-  unsigned long debounce_period_us;
-  struct pollfd polls ;  
+  const char* strmode = "";
+  int ret, attr;
   struct gpio_v2_line_config config;
   struct gpio_v2_line_request req;
-  struct gpio_v2_line_event evdat[64];  
-  struct WPIWfiStatus wfiStatus;
-  struct timespec tspec = {0, 5e5};  /* 0.5 ms timeout {0, 1e6} */
-  
-  pin = *(int *)arg;
 
-  if (wiringPiGpioDeviceGetFd()<0) {
-    return NULL;
+  if (wiringPiGpioDeviceGetFd() < 0) {
+    return -1;
   }
-    
-  EdgeMode = isrEdgeMode[pin];
-  debounce_period_us = isrDebouncePeriodUs[pin];
- 
+
   if (wiringPiDebug) {
     printf ("interruptHandlerV2: GPIO line %d, edge mode %d, debounce_period_us %lu \n", pin, EdgeMode, debounce_period_us) ;
-  } 
-  
+  }
+
   memset(&req, 0, sizeof(req));
   memset(&config, 0, sizeof(config));
-  
+
   /* setup config */
   config.flags = GPIO_V2_LINE_FLAG_INPUT;
   switch(EdgeMode) {
@@ -2911,7 +2902,7 @@ void *interruptHandlerV2(void *arg)
       if (wiringPiDebug) {
         printf ("interruptHandlerV2: waitForInterruptMode edge mode INT_EDGE_SETUP - exiting\n") ;
       }
-      return NULL;
+      return 0;
     case INT_EDGE_FALLING:
       config.flags |= GPIO_V2_LINE_FLAG_EDGE_FALLING;
       strmode = "falling";
@@ -2926,7 +2917,7 @@ void *interruptHandlerV2(void *arg)
       break;
   }
   strcpy(req.consumer, "wiringpi_gpio_irq");
-  
+
   if (debounce_period_us) {
 		attr = config.num_attrs;
 		config.num_attrs++;
@@ -2934,7 +2925,7 @@ void *interruptHandlerV2(void *arg)
 		config.attrs[attr].attr.id = GPIO_V2_LINE_ATTR_ID_DEBOUNCE;
 		config.attrs[attr].attr.debounce_period_us = debounce_period_us;
   }
-  
+
   req.num_lines = 1;
   req.event_buffer_size = 45;
   req.offsets[0] = pin;
@@ -2943,16 +2934,46 @@ void *interruptHandlerV2(void *arg)
   ret = ioctl(chipFd, GPIO_V2_GET_LINE_IOCTL, &req);
   if (ret == -1) {
     ReportDeviceError("interruptHandlerV2: get line event", pin , strmode, ret);
-    return NULL;
+    return -1;
   }
 
-  if (wiringPiDebug) 
-    printf ("interruptHandlerV2: GPIO get line %d , mode %s succeded, fd=%d\n", pin, strmode, req.fd) ;
+  if (wiringPiDebug) {
+    printf ("interruptHandlerV2: GPIO get line %d , mode %s succeded, fd=%d\n", pin, strmode, req.fd);
+  }
+
+  return req.fd;
+}
+
+struct interrupt_handler_params {
+  int pin;
+  int fd;
+};
+
+/*
+ * interruptHandlerV2:
+ *	This is a thread and gets started to wait for the interrupt we're
+ *	hoping to catch. It will call the user-function when the interrupt
+ *	fires.
+ *********************************************************************************
+ */
+
+static void *interruptHandlerV2(void *arg)
+{
+  struct interrupt_handler_params *params;
+  int pin, ret, fd, i;
+  unsigned int readret;
+  struct pollfd polls ;
+  struct gpio_v2_line_event evdat[64];
+  struct WPIWfiStatus wfiStatus;
+  struct timespec tspec = {0, 5e5};  /* 0.5 ms timeout {0, 1e6} */
+
+  params = (struct interrupt_handler_params *)arg;
+  pin = params->pin;
+  fd = params->fd;
 
   /* set event fd  */
-  fd = req.fd;
   isrFds [pin] = fd;
-  
+
   (void)piHiPri (55) ;	// Only effective if we run as root
 
   for (;;) {    // check if event data is available, check if interruptHandlerV2 thread must be canceled
@@ -2961,24 +2982,24 @@ void *interruptHandlerV2(void *arg)
     polls.fd      = fd;
     polls.events  = POLLIN | POLLPRI;
     polls.revents = 0;
-    
+
     // get event data, this is also a cancelation point, when pthread_cancel is called
     ret = ppoll(&polls, 1, &tspec, NULL);     // returns -1 on error, 0 on timeout, >0 number of elements
-  
+
     if (ret < 0) {      // we do not reach this point if canceled, ppoll does not return, is Cancellation Point
-        if (wiringPiDebug)  
+        if (wiringPiDebug)
             printf("interruptHandlerV2: ERROR: poll returned=%d\n", ret);
-        pthread_exit(NULL); 
+        pthread_exit(NULL);
         return NULL;        // never landing here
-    } else if (ret == 0) { 
-//        if (wiringPiDebug)  
+    } else if (ret == 0) {
+//        if (wiringPiDebug)
 //            printf("interruptHandlerV2: timeout: poll returned=%d\n", ret);
         continue;
     }
     else {
         if (wiringPiDebug)
             printf ("interruptHandlerV2: IRQ line %d received %d events, fd=%d\n", pin, ret, isrFds[pin]) ;
-        if (polls.revents & POLLIN) {  
+        if (polls.revents & POLLIN) {
             /* read event data */
             readret = read(fd, &evdat, sizeof(evdat));
             if (readret >= sizeof(evdat[0])) {
@@ -2988,7 +3009,7 @@ void *interruptHandlerV2(void *arg)
                 ret = readret/sizeof(evdat[0]);     // number of events read from fd
                 for (i = 0; i < ret; ++i) {
                     if (isrFunctionsV2[pin]) {
-                        if (wiringPiDebug) 
+                        if (wiringPiDebug)
                             printf( "interruptHandlerV2: GPIO EVENT at %llu on line %u (%u|%u) \n", evdat[i].timestamp_ns, evdat[i].offset, evdat[i].line_seqno, evdat[i].seqno);
                         wfiStatus.statusOK = 1;
                         wfiStatus.pinBCM = pin;
@@ -3005,10 +3026,10 @@ void *interruptHandlerV2(void *arg)
                                 break;
                             default:
                                 wfiStatus.edge = INT_EDGE_SETUP;        // edge = 0
-                                if (wiringPiDebug) 
+                                if (wiringPiDebug)
                                     printf("waitForInterrupt2: unknown event\n");
                                 break;
-                        }        
+                        }
                         wfiStatus.timeStamp_us = evdat[i].timestamp_ns/1000LL;
                         if (wiringPiDebug) {
                           printf( "interruptHandlerV2: call isr function\n");
@@ -3032,7 +3053,7 @@ void *interruptHandlerV2(void *arg)
             else {  // if thread canceled we do not reach this point, read(...) does not return, is Cancellation Point
                 if (wiringPiDebug)
                     printf ("interruptHandlerV2: reading events from fd received signal, exit thread\n");
-                pthread_exit(NULL);  
+                pthread_exit(NULL);
                 return NULL; // never landing here
             }
         }
@@ -3040,9 +3061,8 @@ void *interruptHandlerV2(void *arg)
   }
 }
 
-
 /*
- * wiringPiISR:
+ * wiringPiISRInternal:
  *	Pi Specific.
  *	Take the details and create an interrupt handler that will do a call-
  *	back to the user supplied function.
@@ -3063,38 +3083,48 @@ int wiringPiISRInternal(int pin, int edgeMode, void (*function)(struct WPIWfiSta
     printf("wiringPi: wiringPiISR pin %d, edgeMode %d\n", pin, edgeMode);
   }
   if (isrFunctions[pin] || isrFunctionsV2[pin]) {
-    fprintf(stderr, "wiringPi: ISR function already active, ignoring \n");
+    fprintf(stderr, "wiringPi: ISR function already active\n");
   }
 
-  isrFunctionsV2[pin] = function;
-  isrUserdata[pin] = userdata;
-  isrFunctions[pin] = functionClassic;
-  isrEdgeMode[pin] = edgeMode;
-  isrDebouncePeriodUs[pin] = debounce_period_us;
-  
   if (wiringPiDebug) {
     printf("wiringPi: mutex in\n");
   }
   pthread_mutex_lock (&pinMutex) ;
-    pinPass = pin ;
-    if (wiringPiDebug) {
-      printf("wiringPi: pthread_create before 0x%lX\n", (unsigned long)isrThreads[pin]);
+    struct interrupt_handler_params params = {
+      .pin = pin,
+    };
+    params.fd = interruptHandlerInit(pin, edgeMode, debounce_period_us);
+    if (params.fd < 0) {
+      pthread_mutex_unlock (&pinMutex) ;
+      return -1;
     }
-    if (pthread_create (&isrThreads[pin], NULL, interruptHandlerV2, &pin)==0) {
+
+    // OK to start the new ISR. Update the table.
+    isrFunctionsV2[pin] = function;
+    isrUserdata[pin] = userdata;
+    isrFunctions[pin] = functionClassic;
+    isrEdgeMode[pin] = edgeMode;
+    isrDebouncePeriodUs[pin] = debounce_period_us;
+
+    pinPass = pin ;
+    if (params.fd > 0) {
       if (wiringPiDebug) {
-        printf("wiringPi: pthread_create successed, 0x%lX\n", (unsigned long)isrThreads[pin]);
+        printf("wiringPi: pthread_create before 0x%lX\n", (unsigned long)isrThreads[pin]);
       }
-/*      while (pinPass != -1)
-        delay (1) ; */
-    // wait so that interruptHandler is up und running. 
-    // when interruptHandler is running, the calling function wiringPiISR
-    // must be still alive, otherwise the thread argument &pin points into nirwana,
-    // when it is picked up from interruptHandler.
-      delay (10);
-    } else {
-      if (wiringPiDebug) {
-        printf("wiringPi: pthread_create failed\n");
+      if (pthread_create (&isrThreads[pin], NULL, interruptHandlerV2, &params)==0) {
+        if (wiringPiDebug) {
+          printf("wiringPi: pthread_create successed, 0x%lX\n", (unsigned long)isrThreads[pin]);
+        }
+      } else {
+        if (wiringPiDebug) {
+          printf("wiringPi: pthread_create failed\n");
+        }
       }
+      // wait so that interruptHandler is up und running.
+      // when interruptHandler is running, the calling function wiringPiISRInternal
+      // must be still alive, otherwise the thread argument &param points into nirwana,
+      // when it is picked up from interruptHandlerV2.
+      delay(10);
     }
 
     if (wiringPiDebug) {
@@ -3326,8 +3356,7 @@ int CheckPCIeFileContent(const char* pcieaddress, const char* filename, const ch
 }
 
 
-void GetRP1Memory() {
-
+void GetRP1Memory(void) {
     pciemem_RP1[0] = '\0';
     DIR *dir = opendir(pcie_path);
     struct dirent *entry;
@@ -3360,7 +3389,7 @@ int wiringPiGlobalMemoryAccess(void)
 
   piBoard();
   if (piRP1Model()) {
-    GetRP1Memory(pciemem_RP1, sizeof(pciemem_RP1));
+    GetRP1Memory();
     gpiomemGlobal = pciemem_RP1;
     MMAP_size = pciemem_RP1_Size;
     BaseAddr  = 0x00000000;
@@ -3423,13 +3452,13 @@ int wiringPiSetup (void)
   if (wiringPiSetuped)
     return 0 ;
 
-  wiringPiSetuped = TRUE ;
+  wiringPiSetuped = true ;
 
   if (getenv (ENV_DEBUG) != NULL)
-    wiringPiDebug = TRUE ;
+    wiringPiDebug = true ;
 
   if (getenv (ENV_CODES) != NULL)
-    wiringPiReturnCodes = TRUE ;
+    wiringPiReturnCodes = true ;
 
   if (wiringPiDebug)
     printf ("wiringPi: wiringPiSetup called\n") ;
@@ -3485,7 +3514,7 @@ int wiringPiSetup (void)
     gpioToPwmPort[19] = 3;
   }
 
-  usingGpioMem = FALSE;
+  usingGpioMem = false;
   if (gpiomemGlobal==NULL || (fd = open (gpiomemGlobal, O_RDWR | O_SYNC | O_CLOEXEC)) < 0)
   {
     if (wiringPiDebug) {
@@ -3494,7 +3523,7 @@ int wiringPiSetup (void)
     if (gpiomemModule && (fd = open (gpiomemModule, O_RDWR | O_SYNC | O_CLOEXEC) ) >= 0)	// We're using gpiomem
     {
       piGpioBase   = 0 ;
-      usingGpioMem = TRUE ;
+      usingGpioMem = true ;
     }
     else
       return wiringPiFailure (WPI_ALMOST, "wiringPiSetup: Unable to open %s or %s: %s.\n"
@@ -3678,15 +3707,15 @@ int wiringPiSetupGpioDevice (enum WPIPinType pinType) {
     printf ("wiringPi: wiringPiSetupGpioDevice(%d) called\n", (int)pinType) ;
   }
   if (getenv (ENV_DEBUG) != NULL)
-    wiringPiDebug = TRUE ;
+    wiringPiDebug = true ;
 
   if (getenv (ENV_CODES) != NULL)
-    wiringPiReturnCodes = TRUE ;
+    wiringPiReturnCodes = true ;
 
   if (wiringPiGpioDeviceGetFd()<0) {
     return -1;
   }
-  wiringPiSetuped = TRUE ;
+  wiringPiSetuped = true ;
 
   if (piGpioLayout () == GPIO_LAYOUT_PI1_REV1){
     pinToGpio  = pinToGpioR1 ;
@@ -3709,7 +3738,7 @@ int wiringPiSetupGpioDevice (enum WPIPinType pinType) {
       wiringPiMode = WPI_MODE_GPIO_DEVICE_PHYS;
       break;
     default:
-      wiringPiSetuped = FALSE;
+      wiringPiSetuped = false;
       return -1;
   }
 
diff --git a/wiringPi/wiringPi.h b/wiringPi/wiringPi.h
index aa3c753..07cd258 100644
--- a/wiringPi/wiringPi.h
+++ b/wiringPi/wiringPi.h
@@ -1,7 +1,7 @@
 /*
  * wiringPi.h:
  *	Arduino like Wiring library for the Raspberry Pi.
- *	Copyright (c) 2012-2025 Gordon Henderson
+ *	Copyright (c) 2012–2019 Gordon Henderson; 2019–2026 Contributors
  ***********************************************************************
  * This file is part of wiringPi:
  *	https://github.com/WiringPi/WiringPi/
@@ -24,13 +24,14 @@
 #ifndef	__WIRING_PI_H__
 #define	__WIRING_PI_H__
 
-// C doesn't have true/false by default and I can never remember which
-//	way round they are, so ...
-//	(and yes, I know about stdbool.h but I like capitals for these and I'm old)
+#include <stdbool.h>
 
-#ifndef	TRUE
-#  define	TRUE	(1==1)
-#  define	FALSE	(!TRUE)
+// macros retained for old code compatibility, we now use stdbool.h
+#ifndef TRUE
+  #define TRUE true
+#endif
+#ifndef FALSE
+  #define FALSE false
 #endif
 
 // GCC warning suppressor
diff --git a/wiringPi/wiringPiI2C.c b/wiringPi/wiringPiI2C.c
index 95131c3..6ec1789 100644
--- a/wiringPi/wiringPiI2C.c
+++ b/wiringPi/wiringPiI2C.c
@@ -1,7 +1,7 @@
 /*
  * wiringPiI2C.c:
  *	Simplified I2C access routines
- *	Copyright (c) 2013-2024 Gordon Henderson and contributors
+ *	Copyright (c) 2013–2019 Gordon Henderson; 2019–2026 Contributors
  ***********************************************************************
  * This file is part of wiringPi:
  *	https://github.com/WiringPi/WiringPi/
diff --git a/wiringPi/wiringPiI2C.h b/wiringPi/wiringPiI2C.h
index 112257a..22df490 100644
--- a/wiringPi/wiringPiI2C.h
+++ b/wiringPi/wiringPiI2C.h
@@ -1,7 +1,7 @@
 /*
  * wiringPiI2C.h:
  *	Simplified I2C access routines
- *	Copyright (c) 2013-2024 Gordon Henderson and contributors
+ *	Copyright (c) 2013–2019 Gordon Henderson; 2019–2026 Contributors
  ***********************************************************************
  * This file is part of wiringPi:
  *	https://github.com/WiringPi/WiringPi/
diff --git a/wiringPi/wiringPiSPI.c b/wiringPi/wiringPiSPI.c
index 581a079..840f175 100644
--- a/wiringPi/wiringPiSPI.c
+++ b/wiringPi/wiringPiSPI.c
@@ -1,7 +1,7 @@
 /*
  * wiringPiSPI.c:
  *	Simplified SPI access routines
- *	Copyright (c) 2012-2025 Gordon Henderson and contributors
+ *	Copyright (c) 2012–2019 Gordon Henderson; 2019–2026 Contributors
  ***********************************************************************
  * This file is part of wiringPi:
  *	https://github.com/WiringPi/WiringPi/
@@ -44,9 +44,11 @@
 //static const char       *spiDev1  = "/dev/spidev0.1" ;
 static const uint8_t     spiBPW   = 8 ;
 static const uint16_t    spiDelay = 0 ;
-//https://datasheets.raspberrypi.com/cm4/cm4-datasheet.pdf
+//https://datasheets.raspberrypi.com/cm4/cm4-datasheet.pdf   SPI0-6, CS0-2
+//cm5-datasheet.pdf                                          SPI0-5, CS depend on SPInumber, can be up to 4
+//spi0-4cs.dts                                               extention for supporting CS0-4
 const uint8_t     WPI_MaxSPINumbers   = 7 ;
-const uint8_t     WPI_MaxSPIChannels  = 3 ;
+const uint8_t     WPI_MaxSPIChannels  = 5 ;
 
 
 static uint32_t    spiSpeeds [7][3] =
diff --git a/wiringPi/wiringPiSPI.h b/wiringPi/wiringPiSPI.h
index d60b064..aa15aa6 100644
--- a/wiringPi/wiringPiSPI.h
+++ b/wiringPi/wiringPiSPI.h
@@ -1,7 +1,7 @@
 /*
  * wiringPiSPI.h:
  *	Simplified SPI access routines
- *	Copyright (c) 2012-2025 Gordon Henderson and contributors
+ *	Copyright (c) 2012–2019 Gordon Henderson; 2019–2026 Contributors
  ***********************************************************************
  * This file is part of wiringPi:
  *	https://github.com/WiringPi/WiringPi/
diff --git a/wiringPi/wpiExtensions.c b/wiringPi/wpiExtensions.c
index 8668806..572a4bc 100644
--- a/wiringPi/wpiExtensions.c
+++ b/wiringPi/wpiExtensions.c
@@ -27,6 +27,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <stdarg.h>
 #include <ctype.h>
@@ -146,7 +147,7 @@ static char *extractInt (char *progName, char *p, int *num)
 static char *extractStr (char *progName, char *p, char **str)
 {
   char *q, *r ;
-  int quoted = FALSE ;
+  int quoted = false ;
 
   if (*p != ':')
   {
@@ -158,7 +159,7 @@ static char *extractStr (char *progName, char *p, char **str)
 
   if (*p == '[')
   {
-    quoted = TRUE ;
+    quoted = true ;
     ++p ;
   }
 
@@ -205,17 +206,17 @@ static int doExtensionMcp23008 (char *progName, int pinBase, char *params)
   int i2c ;
 
   if ((params = extractInt (progName, params, &i2c)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((i2c < 0x01) || (i2c > 0x77))
   {
     verbError ("%s: i2c address (0x%X) out of range", progName, i2c) ;
-    return FALSE ;
+    return false ;
   }
 
   mcp23008Setup (pinBase, i2c) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -231,17 +232,17 @@ static int doExtensionMcp23016 (char *progName, int pinBase, char *params)
   int i2c ;
 
   if ((params = extractInt (progName, params, &i2c)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((i2c < 0x03) || (i2c > 0x77))
   {
     verbError ("%s: i2c address (0x%X) out of range", progName, i2c) ;
-    return FALSE ;
+    return false ;
   }
 
   mcp23016Setup (pinBase, i2c) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -257,17 +258,17 @@ static int doExtensionMcp23017 (char *progName, int pinBase, char *params)
   int i2c ;
 
   if ((params = extractInt (progName, params, &i2c)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((i2c < 0x03) || (i2c > 0x77))
   {
     verbError ("%s: i2c address (0x%X) out of range", progName, i2c) ;
-    return FALSE ;
+    return false ;
   }
 
   mcp23017Setup (pinBase, i2c) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -283,26 +284,26 @@ static int doExtensionMcp23s08 (char *progName, int pinBase, char *params)
   int spi, port ;
 
   if ((params = extractInt (progName, params, &spi)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((spi < 0) || (spi > 1))
   {
     verbError ("%s: SPI address (%d) out of range", progName, spi) ;
-    return FALSE ;
+    return false ;
   }
 
   if ((params = extractInt (progName, params, &port)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((port < 0) || (port > 7))
   {
     verbError ("%s: port address (%d) out of range", progName, port) ;
-    return FALSE ;
+    return false ;
   }
 
   mcp23s08Setup (pinBase, spi, port) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -318,26 +319,26 @@ static int doExtensionMcp23s17 (char *progName, int pinBase, char *params)
   int spi, port ;
 
   if ((params = extractInt (progName, params, &spi)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((spi < 0) || (spi > 1))
   {
     verbError ("%s: SPI address (%d) out of range", progName, spi) ;
-    return FALSE ;
+    return false ;
   }
 
   if ((params = extractInt (progName, params, &port)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((port < 0) || (port > 7))
   {
     verbError ("%s: port address (%d) out of range", progName, port) ;
-    return FALSE ;
+    return false ;
   }
 
   mcp23s17Setup (pinBase, spi, port) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -355,26 +356,26 @@ static int doExtensionSr595 (char *progName, int pinBase, char *params)
 // Extract pins
 
   if ((params = extractInt (progName, params, &pins)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((pins < 8) || (pins > 32))
   {
     verbError ("%s: pin count (%d) out of range - 8-32 expected.", progName, pins) ;
-    return FALSE ;
+    return false ;
   }
 
   if ((params = extractInt (progName, params, &data)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((params = extractInt (progName, params, &clock)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((params = extractInt (progName, params, &latch)) == NULL)
-    return FALSE ;
+    return false ;
 
   sr595Setup (pinBase, pins, data, clock, latch) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -390,17 +391,17 @@ static int doExtensionPcf8574 (char *progName, int pinBase, char *params)
   int i2c ;
 
   if ((params = extractInt (progName, params, &i2c)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((i2c < 0x03) || (i2c > 0x77))
   {
     verbError ("%s: i2c address (0x%X) out of range", progName, i2c) ;
-    return FALSE ;
+    return false ;
   }
 
   pcf8574Setup (pinBase, i2c) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -416,17 +417,17 @@ static int doExtensionAds1115 (char *progName, int pinBase, char *params)
   int i2c ;
 
   if ((params = extractInt (progName, params, &i2c)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((i2c < 0x03) || (i2c > 0x77))
   {
     verbError ("%s: i2c address (0x%X) out of range", progName, i2c) ;
-    return FALSE ;
+    return false ;
   }
 
   ads1115Setup (pinBase, i2c) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -442,17 +443,17 @@ static int doExtensionPcf8591 (char *progName, int pinBase, char *params)
   int i2c ;
 
   if ((params = extractInt (progName, params, &i2c)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((i2c < 0x03) || (i2c > 0x77))
   {
     verbError ("%s: i2c address (0x%X) out of range", progName, i2c) ;
-    return FALSE ;
+    return false ;
   }
 
   pcf8591Setup (pinBase, i2c) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -467,7 +468,7 @@ static int doExtensionPseudoPins (UNU char *progName, int pinBase, UNU char *par
 {
   pseudoPinsSetup (pinBase) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -482,7 +483,7 @@ static int doExtensionBmp180 (UNU char *progName, int pinBase, UNU char *params)
 {
   bmp180Setup (pinBase) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -497,7 +498,7 @@ static int doExtensionHtu21d (UNU char *progName, int pinBase, UNU char *params)
 {
   htu21dSetup (pinBase) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -513,7 +514,7 @@ static int doExtensionDs18b20 (char *progName, int pinBase, char *params)
   char *serialNum ;
 
   if ((params = extractStr (progName, params, &serialNum)) == NULL)
-    return FALSE ;
+    return false ;
 
   return ds18b20Setup (pinBase, serialNum) ;
 }
@@ -531,7 +532,7 @@ static int doExtensionRht03 (char *progName, int pinBase, char *params)
   int piPin ;
 
   if ((params = extractInt (progName, params, &piPin)) == NULL)
-    return FALSE ;
+    return false ;
 
   return rht03Setup (pinBase, piPin) ;
 }
@@ -549,17 +550,17 @@ static int doExtensionMax31855 (char *progName, int pinBase, char *params)
   int spi ;
 
   if ((params = extractInt (progName, params, &spi)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((spi < 0) || (spi > 1))
   {
     verbError ("%s: SPI channel (%d) out of range", progName, spi) ;
-    return FALSE ;
+    return false ;
   }
 
   max31855Setup (pinBase, spi) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -575,17 +576,17 @@ static int doExtensionMcp3002 (char *progName, int pinBase, char *params)
   int spi ;
 
   if ((params = extractInt (progName, params, &spi)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((spi < 0) || (spi > 1))
   {
     verbError ("%s: SPI channel (%d) out of range", progName, spi) ;
-    return FALSE ;
+    return false ;
   }
 
   mcp3002Setup (pinBase, spi) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -601,17 +602,17 @@ static int doExtensionMcp3004 (char *progName, int pinBase, char *params)
   int spi ;
 
   if ((params = extractInt (progName, params, &spi)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((spi < 0) || (spi > 1))
   {
     verbError ("%s: SPI channel (%d) out of range", progName, spi) ;
-    return FALSE ;
+    return false ;
   }
 
   mcp3004Setup (pinBase, spi) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -627,17 +628,17 @@ static int doExtensionMax5322 (char *progName, int pinBase, char *params)
   int spi ;
 
   if ((params = extractInt (progName, params, &spi)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((spi < 0) || (spi > 1))
   {
     verbError ("%s: SPI channel (%d) out of range", progName, spi) ;
-    return FALSE ;
+    return false ;
   }
 
   max5322Setup (pinBase, spi) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -653,17 +654,17 @@ static int doExtensionMcp4802 (char *progName, int pinBase, char *params)
   int spi ;
 
   if ((params = extractInt (progName, params, &spi)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((spi < 0) || (spi > 1))
   {
     verbError ("%s: SPI channel (%d) out of range", progName, spi) ;
-    return FALSE ;
+    return false ;
   }
 
   mcp4802Setup (pinBase, spi) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -677,7 +678,7 @@ static int doExtensionMcp4802 (char *progName, int pinBase, char *params)
 static int doExtensionSn3218 (UNU char *progName, int pinBase, UNU char *params)
 {
   sn3218Setup (pinBase) ;
-  return TRUE ;
+  return true ;
 }
 
 
@@ -693,35 +694,35 @@ static int doExtensionMcp3422 (char *progName, int pinBase, char *params)
   int i2c, sampleRate, gain ;
 
   if ((params = extractInt (progName, params, &i2c)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((i2c < 0x03) || (i2c > 0x77))
   {
     verbError ("%s: i2c address (0x%X) out of range", progName, i2c) ;
-    return FALSE ;
+    return false ;
   }
 
   if ((params = extractInt (progName, params, &sampleRate)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((sampleRate < 0) || (sampleRate > 3))
   {
     verbError ("%s: sample rate (%d) out of range", progName, sampleRate) ;
-    return FALSE ;
+    return false ;
   }
 
   if ((params = extractInt (progName, params, &gain)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((gain < 0) || (gain > 3))
   {
     verbError ("%s: gain (%d) out of range", progName, gain) ;
-    return FALSE ;
+    return false ;
   }
 
   mcp3422Setup (pinBase, i2c, sampleRate, gain) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -738,35 +739,35 @@ static int doExtensionDrcS (char *progName, int pinBase, char *params)
   int pins, baud ;
 
   if ((params = extractInt (progName, params, &pins)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((pins < 1) || (pins > 1000))
   {
     verbError ("%s: pins (%d) out of range (2-1000)", progName, pins) ;
-    return FALSE ;
+    return false ;
   }
   
   if ((params = extractStr (progName, params, &port)) == NULL)
-    return FALSE ;
+    return false ;
 
   if (strlen (port) == 0)
   {
     verbError ("%s: serial port device name required", progName) ;
-    return FALSE ;
+    return false ;
   }
 
   if ((params = extractInt (progName, params, &baud)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((baud < 1) || (baud > 4000000))
   {
     verbError ("%s: baud rate (%d) out of range", progName, baud) ;
-    return FALSE ;
+    return false ;
   }
 
   drcSetupSerial (pinBase, pins, port, baud) ;
 
-  return TRUE ;
+  return true ;
 }
 
 
@@ -784,25 +785,25 @@ static int doExtensionDrcNet (char *progName, int pinBase, char *params)
   char pPort [1024] ;
 
   if ((params = extractInt (progName, params, &pins)) == NULL)
-    return FALSE ;
+    return false ;
 
   if ((pins < 1) || (pins > 1000))
   {
     verbError ("%s: pins (%d) out of range (2-1000)", progName, pins) ;
-    return FALSE ;
+    return false ;
   }
   
   if ((params = extractStr (progName, params, &ipAddress)) == NULL)
-    return FALSE ;
+    return false ;
 
   if (strlen (ipAddress) == 0)
   {
     verbError ("%s: ipAddress required", progName) ;
-    return FALSE ;
+    return false ;
   }
 
   if ((params = extractStr (progName, params, &port)) == NULL)
-    return FALSE ;
+    return false ;
 
   if (strlen (port) == 0)
   {
@@ -811,12 +812,12 @@ static int doExtensionDrcNet (char *progName, int pinBase, char *params)
   }
 
   if ((params = extractStr (progName, params, &password)) == NULL)
-    return FALSE ;
+    return false ;
 
   if (strlen (password) == 0)
   {
     verbError ("%s: password required", progName) ;
-    return FALSE ;
+    return false ;
   }
 
   return drcSetupNet (pinBase, pins, ipAddress, port, password) ;
@@ -883,7 +884,7 @@ int loadWPiExtension (char *progName, char *extensionData, int printErrors)
     if (!*p)	// ran out of characters
     {
       verbError ("%s: extension name not terminated by a colon", progName) ;
-      return FALSE ;
+      return false ;
     }
     ++p ;
   }
@@ -894,7 +895,7 @@ int loadWPiExtension (char *progName, char *extensionData, int printErrors)
   if (!isdigit (*p))
   {
     verbError ("%s: decimal pinBase number expected after extension name", progName) ;
-    return FALSE ;
+    return false ;
   }
 
   while (isdigit (*p))
@@ -902,7 +903,7 @@ int loadWPiExtension (char *progName, char *extensionData, int printErrors)
     if (pinBase > 2147483647) // 2^31-1 ... Lets be realistic here...
     {
       verbError ("%s: pinBase too large", progName) ;
-      return FALSE ;
+      return false ;
     }
 
     pinBase = pinBase * 10 + (*p - '0') ;
@@ -912,7 +913,7 @@ int loadWPiExtension (char *progName, char *extensionData, int printErrors)
   if (pinBase < 64)
   {
     verbError ("%s: pinBase (%d) too small. Minimum is 64.", progName, pinBase) ;
-    return FALSE ;
+    return false ;
   }
 
 // Search for extensions:
@@ -924,5 +925,5 @@ int loadWPiExtension (char *progName, char *extensionData, int printErrors)
   }
 
   fprintf (stderr, "%s: extension %s not found", progName, extension) ;
-  return FALSE ;
+  return false ;
 }
diff --git a/wiringPiD/network.c b/wiringPiD/network.c
index 0c58d3b..f8636c7 100644
--- a/wiringPiD/network.c
+++ b/wiringPiD/network.c
@@ -26,6 +26,7 @@
 #include <arpa/inet.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <unistd.h>
 #include <string.h>
 #include <stdarg.h>
@@ -36,9 +37,6 @@
 
 #include "network.h"
 
-#define	TRUE	(1==1)
-#define	FALSE	(!TRUE)
-
 // Local data
 
 #define	SALT_LEN	16
diff --git a/wiringPiD/runRemote.c b/wiringPiD/runRemote.c
index d00ddf2..913c1ed 100644
--- a/wiringPiD/runRemote.c
+++ b/wiringPiD/runRemote.c
@@ -26,6 +26,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdint.h>
+#include <stdbool.h>
 #include <unistd.h>
 #include <string.h>
 #include <errno.h>
@@ -40,7 +41,7 @@
 
 
 
-int noLocalPins = FALSE ;
+int noLocalPins = false ;
 
 
 void runRemoteCommands (int fd)
diff --git a/wiringPiD/wiringpid.c b/wiringPiD/wiringpid.c
index 235e290..3eb02e2 100644
--- a/wiringPiD/wiringpid.c
+++ b/wiringPiD/wiringpid.c
@@ -22,6 +22,7 @@
 
 #include <arpa/inet.h>
 #include <stdio.h>
+#include <stdbool.h>
 #include <stdlib.h>
 #include <stdint.h>
 #include <unistd.h>
@@ -46,7 +47,7 @@
 // Globals
 
 static const char *usage = "[-h] [-d] [-g | -1 | -z] [[-x extension:pin:params] ...] password" ;
-static int doDaemon = FALSE ;
+static int doDaemon = false ;
 
 //
 
@@ -156,7 +157,7 @@ int main (int argc, char *argv [])
       exit (EXIT_FAILURE) ;
     }
 
-    doDaemon = TRUE ;
+    doDaemon = true ;
     daemonise (PIDFILE) ;
 
     for (i = 2 ; i < argc ; ++i)
@@ -216,7 +217,7 @@ int main (int argc, char *argv [])
       for (i = 2 ; i < argc ; ++i)
 	argv [i - 1] = argv [i] ;
       --argc ;
-      noLocalPins = TRUE ;
+      noLocalPins = true ;
       ++wpiSetup ;
       continue ;
     }
@@ -263,7 +264,7 @@ int main (int argc, char *argv [])
 
       logMsg ("Loading extension: %s", argv [2]) ;
 
-      if (!loadWPiExtension (argv [0], argv [2], TRUE))
+      if (!loadWPiExtension (argv [0], argv [2], true))
       {
 	logMsg ("Extension load failed: %s", strerror (errno)) ;
 	exit (EXIT_FAILURE) ;