diff --git a/wiringPi/test/Makefile b/wiringPi/test/Makefile
index 764201b..5c711cb 100644
--- a/wiringPi/test/Makefile
+++ b/wiringPi/test/Makefile
@@ -41,7 +41,7 @@ wiringpi_i2c_test1_pcf8574:
 	${CC} ${CFLAGS} wiringpi_i2c_test1_pcf8574.c -o wiringpi_i2c_test1_pcf8574 -lwiringPi
 
 wiringpi_piface_test1:
-	${CC} ${CFLAGS} wiringpi_piface_test1.c -o wiringpi_piface_test1 -lwiringPi
+	${CC} ${CFLAGS} wiringpi_piface_test1.c -o wiringpi_piface_test1 -lwiringPi -lwiringPiDev
 
 test:
 	@error_state=false ; \
diff --git a/wiringPi/test/wiringpi_piface_test1.c b/wiringPi/test/wiringpi_piface_test1.c
index 686efdb..c70861b 100644
--- a/wiringPi/test/wiringpi_piface_test1.c
+++ b/wiringPi/test/wiringpi_piface_test1.c
@@ -1,17 +1,130 @@
-#include "wpi_test.h"
-#include "../../version.h"
+// WiringPi piface program IN, OUT, PULL
+// Compile: gcc -Wall wiringpi_piface_test1.c -o wiringpi_piface_test1 -lwiringPi -lwiringPiDev
 
-// PiFace dummy
+#include "wpi_test.h"
+#include <piFace.h>
 
-int main (void) {
-  int major, minor;
+// Use 200 as the pin-base for the PiFace board, and change all pins
+//	for the LED and relays
 
+const int PIFACE = 200;          //Mapped wiringpi IO address
+const int defaultsleep = 200000; // 200 ms
 
-  wiringPiVersion(&major, &minor);
-  printf("Testing piface functions with WiringPi %d.%d\n",major, minor);
-  printf("------------------------------------------\n\n");
-
-
-
-  return UnitTestState();
+void ReadUntilTimeout(int GPIO, int expect, int timeoutSec) {
+	const int intervaluS =  250000; //250ms
+	int in;
+	const char* strexpect = expect ? "HIGH" : "LOW";
+	for(int loop=0, end=(timeoutSec*1000000/intervaluS); loop<end; ++loop) {
+		in = digitalRead(GPIO);
+		if (in==expect) {
+			printf( "took %g sec to set %s\n", loop*intervaluS/1000000.0, strexpect);
+			break;
+		}
+		delayMicroseconds(intervaluS);
+		printf(".");fflush(stdout);
+	}
+	if (in!=expect) {
+		printf( "timeout reached %d sec to set %s\n", timeoutSec, strexpect);
+	}
+	CheckGPIO(GPIO, -1, expect) ;
+}
+
+int main (int argc, char *argv []) {
+    int major, minor;
+
+    wiringPiVersion(&major, &minor);
+    printf("Testing piface functions with WiringPi %d.%d\n",major, minor);
+    printf("------------------------------------------\n\n");
+
+	// initialise wiringPi
+	if (wiringPiSetupSys()  == -1) {
+		printf("wiringPiSetupSys failed\n\n");
+		exit(EXIT_FAILURE);
+	}
+
+	piFaceSetup (PIFACE); // Setup the PiFace board with default addr 0, 0
+
+	const int RELAY0 = PIFACE+0;
+	const int RELAY0IN = PIFACE+6;
+	const int RELAY1 = PIFACE+1;
+	const int RELAY1IN = PIFACE+7;
+
+	printf("\nRelays async:\n");
+	for (int loop = 0, end=3 ; loop<end ; ++loop) {
+		int sleep = defaultsleep*(end-loop);
+		printf("sleep %d ms:\n", sleep/1000);
+		digitalWrite (RELAY0, HIGH);
+		delayMicroseconds(sleep);
+		CheckInversGPIO(RELAY0IN, -1, HIGH) ;
+		digitalWrite (RELAY0, LOW);
+		delayMicroseconds(sleep);
+		CheckInversGPIO(RELAY0IN, -1, LOW);
+
+		digitalWrite (RELAY1, HIGH);
+		delayMicroseconds(sleep);
+		CheckInversGPIO(RELAY1IN, -1, HIGH);
+		digitalWrite (RELAY1, LOW);
+		delayMicroseconds(sleep);
+		CheckInversGPIO(RELAY1IN, -1, LOW);
+	}
+
+	const int OUT7 = PIFACE+7;
+	const int OUT7IN = PIFACE+4;
+	const int OUT6 = PIFACE+6;
+	const int OUT6IN = PIFACE+5;
+
+	printf("\nOUT6/7 sync:\n");
+	delayMicroseconds(defaultsleep);
+	for (int loop = 0, end=3 ; loop<end ; ++loop) {
+		digitalWrite (OUT7, HIGH);
+		delayMicroseconds(defaultsleep);
+		CheckInversGPIO(OUT7IN, -1, HIGH);
+
+		digitalWrite (OUT7, LOW);
+		delayMicroseconds(defaultsleep);
+		CheckInversGPIO(OUT7IN, -1, LOW);
+
+		digitalWrite (OUT6, HIGH);
+		delayMicroseconds(defaultsleep);
+		CheckInversGPIO(OUT6IN, -1, HIGH);
+
+		digitalWrite (OUT6, LOW);
+		delayMicroseconds(defaultsleep);
+		CheckInversGPIO(OUT6IN, -1, LOW);
+	}
+
+	printf("\nRelays sync:\n");
+	for (int loop = 0, end=3 ; loop<end ; ++loop) {
+		int sleep = defaultsleep*(end-loop);
+		printf("sleep %d ms:\n", sleep/1000);
+		digitalWrite (RELAY0, HIGH);
+		digitalWrite (RELAY1, HIGH);
+		delayMicroseconds(sleep);
+		CheckInversGPIO(RELAY0IN, -1, HIGH) ;
+		CheckInversGPIO(RELAY1IN, -1, HIGH) ;
+
+		digitalWrite (RELAY0, LOW);
+		digitalWrite (RELAY1, LOW);
+		delayMicroseconds(sleep);
+		CheckInversGPIO(RELAY0IN, -1, LOW) ;
+		CheckInversGPIO(RELAY1IN, -1, LOW) ;
+	}
+
+	printf("\nInput pull up/down resistor:\n");
+	for (int IN = 0 ; IN <= 7 ; ++IN) {
+		if (4==IN || 5==IN) {
+			continue;  //4 & 5 connected from out to in -> test not possible
+		}
+		//6 & 7 connected from relais NO (normaly open) to in  -> test possible
+		delayMicroseconds(defaultsleep);
+		pullUpDnControl (PIFACE + IN, PUD_UP) ;
+		ReadUntilTimeout(PIFACE + IN, HIGH, 2) ;
+		pullUpDnControl (PIFACE + IN, PUD_DOWN) ;
+		// cool down very slowly, connect 680 kOhm pull down resistor to make ist faster
+		ReadUntilTimeout(PIFACE + IN, LOW, 60) ;
+		pullUpDnControl (PIFACE + IN, PUD_UP) ;  // finally up
+		ReadUntilTimeout(PIFACE + IN, HIGH, 2) ;
+	}
+
+	return UnitTestState();
 }
diff --git a/wiringPi/test/wiringpi_test1_sysfs.c b/wiringPi/test/wiringpi_test1_sysfs.c
index 45a62fe..a97f85e 100644
--- a/wiringPi/test/wiringpi_test1_sysfs.c
+++ b/wiringPi/test/wiringpi_test1_sysfs.c
@@ -7,8 +7,8 @@
 #include <sys/time.h>
 
 
-const int GPIO = 19;
-const int GPIOIN = 26;
+int GPIO = 19;
+int GPIOIN = 26;
 const int ToggleValue = 4;
 
 
@@ -21,6 +21,11 @@ int main (void) {
 		printf("wiringPiSetupSys failed\n\n");
 		exit(EXIT_FAILURE);
 	}
+	if (!piBoard40Pin()) {
+		GPIO = 23;
+		GPIOIN = 24;
+	}
+	
 	pinMode(GPIOIN, INPUT);
 	pinMode(GPIO, OUTPUT);
 
diff --git a/wiringPi/test/wiringpi_test2_sysfs.c b/wiringPi/test/wiringpi_test2_sysfs.c
index 0e5a0d2..76c48d3 100644
--- a/wiringPi/test/wiringpi_test2_sysfs.c
+++ b/wiringPi/test/wiringpi_test2_sysfs.c
@@ -7,8 +7,8 @@
 #include <sys/time.h>
 
 
-const int GPIO = 19;
-const int GPIOIN = 26;
+int GPIO = 19;
+int GPIOIN = 26;
 const int ToggleValue = 4;
 
 
@@ -21,6 +21,11 @@ int main (void) {
 		printf("wiringPiSetupSys failed\n\n");
 		exit(EXIT_FAILURE);
 	}
+	if (!piBoard40Pin()) {
+		GPIO = 23;
+		GPIOIN = 24;
+	}
+	
 	pinMode(GPIOIN, INPUT);
 	pinMode(GPIO, OUTPUT);
 
diff --git a/wiringPi/test/wiringpi_test3_device_wpi.c b/wiringPi/test/wiringpi_test3_device_wpi.c
index 24af1bc..4176459 100644
--- a/wiringPi/test/wiringpi_test3_device_wpi.c
+++ b/wiringPi/test/wiringpi_test3_device_wpi.c
@@ -7,8 +7,8 @@
 #include <sys/time.h>
 
 
-const int GPIO = 24; //BCM 19
-const int GPIOIN = 25; //BCM 26;
+int GPIO = 24; //BCM 19
+int GPIOIN = 25; //BCM 26;
 const int ToggleValue = 4;
 
 
@@ -21,6 +21,11 @@ int main (void) {
 		printf("wiringPiSetupGpioDevice failed\n\n");
 		exit(EXIT_FAILURE);
 	}
+	if (!piBoard40Pin()) {
+		GPIO = 4;  //BCM 23
+		GPIOIN = 5;  //BCM 24
+	}
+	
 	pinMode(GPIOIN, INPUT);
 	pinMode(GPIO, OUTPUT);
 
diff --git a/wiringPi/test/wiringpi_test4_device_phys.c b/wiringPi/test/wiringpi_test4_device_phys.c
index ecd07a5..31157b8 100644
--- a/wiringPi/test/wiringpi_test4_device_phys.c
+++ b/wiringPi/test/wiringpi_test4_device_phys.c
@@ -7,8 +7,8 @@
 #include <sys/time.h>
 
 
-const int GPIO = 35; //BCM 19
-const int GPIOIN = 37; //BCM 26;
+int GPIO = 35; //BCM 19
+int GPIOIN = 37; //BCM 26;
 const int ToggleValue = 4;
 
 
@@ -21,6 +21,11 @@ int main (void) {
 		printf("wiringPiSetupGpioDevice failed\n\n");
 		exit(EXIT_FAILURE);
 	}
+	if (!piBoard40Pin()) {
+		GPIO = 16;  //BCM 23
+		GPIOIN = 18;  //BCM 24
+	}
+	
 	pinMode(GPIOIN, INPUT);
 	pinMode(GPIO, OUTPUT);
 
diff --git a/wiringPi/test/wiringpi_test5_default.c b/wiringPi/test/wiringpi_test5_default.c
index 8223090..ecf80bf 100644
--- a/wiringPi/test/wiringpi_test5_default.c
+++ b/wiringPi/test/wiringpi_test5_default.c
@@ -7,8 +7,8 @@
 #include <sys/time.h>
 
 
-const int GPIO = 19;
-const int GPIOIN = 26;
+int GPIO = 19;
+int GPIOIN = 26;
 const int ToggleValue = 4;
 int RaspberryPiModel = -1;
 
@@ -58,6 +58,10 @@ int main (void) {
 	} else {
 		printf("Raspberry Pi with BCM GPIO found (not Pi 5)\n");
 	}
+	if (!piBoard40Pin()) {
+		GPIO = 23;
+		GPIOIN = 24;
+	}
 
 
 	enum WPIPinAlt AltGpio = WPI_ALT_UNKNOWN;
diff --git a/wiringPi/test/wiringpi_test6_isr.c b/wiringPi/test/wiringpi_test6_isr.c
index 24f1496..644fa50 100644
--- a/wiringPi/test/wiringpi_test6_isr.c
+++ b/wiringPi/test/wiringpi_test6_isr.c
@@ -8,8 +8,8 @@
 #include <sys/time.h>
 
 
-const int GPIO = 19;
-const int GPIOIN = 26;
+int GPIO = 19;
+int GPIOIN = 26;
 const int ToggleValue = 4;
 
 
@@ -115,55 +115,61 @@ double DurationTime(int Enge, int OUTpin, int IRQpin) {
   return fTime;
 }
 
-int main (void) {
-  const int IRQpin = GPIOIN ;
-  const int OUTpin = GPIO ;
-  int major, minor;
 
-  wiringPiVersion(&major, &minor);
+int main (void) {
+
+	int major, minor;
+
+	wiringPiVersion(&major, &minor);
 
 	printf("WiringPi GPIO test program 1 (using GPIO%d (output) and GPIO%d (input))\n", GPIO, GPIOIN);
 	printf(" testing irq\n");
 
-  printf("\nISR test (WiringPi %d.%d)\n", major, minor);
+	printf("\nISR test (WiringPi %d.%d)\n", major, minor);
 
-  wiringPiSetupGpio() ;
-
-  pinMode(IRQpin, INPUT);
-  pinMode(OUTpin, OUTPUT);
-  digitalWrite (OUTpin, LOW) ;
+	wiringPiSetupGpio() ;
+	if (!piBoard40Pin()) {
+		GPIO = 23;
+		GPIOIN = 24;
+	}
+	int IRQpin = GPIOIN ;
+	int OUTpin = GPIO ;
+	
+	pinMode(IRQpin, INPUT);
+	pinMode(OUTpin, OUTPUT);
+	digitalWrite (OUTpin, LOW) ;
 
 
-  printf("Testing IRQ @ GPIO%d with trigger @ GPIO%d rising\n", IRQpin, OUTpin);
-  wiringPiISR (IRQpin, INT_EDGE_RISING, &wfi) ;
-  sleep(1);
-  StartSequence (INT_EDGE_RISING, OUTpin);
-  printf("Testing close\n");
-  
-  wiringPiISRStop (IRQpin) ;
+	printf("Testing IRQ @ GPIO%d with trigger @ GPIO%d rising\n", IRQpin, OUTpin);
+	wiringPiISR (IRQpin, INT_EDGE_RISING, &wfi) ;
+	sleep(1);
+	StartSequence (INT_EDGE_RISING, OUTpin);
+	printf("Testing close\n");
 
-  printf("Testing IRQ @ GPIO%d with trigger @ GPIO%d falling\n", IRQpin, OUTpin);
-  wiringPiISR (IRQpin, INT_EDGE_FALLING, &wfi) ;
-  sleep(1);
-  StartSequence (INT_EDGE_FALLING, OUTpin);
-  printf("Testing close\n");
-  wiringPiISRStop (IRQpin) ;
+	wiringPiISRStop (IRQpin) ;
 
-  printf("Testing IRQ @ GPIO%d with trigger @ GPIO%d both\n", IRQpin, OUTpin);
-  wiringPiISR (IRQpin, INT_EDGE_BOTH, &wfi) ;
-  sleep(1);
-  StartSequence (INT_EDGE_BOTH, OUTpin);
-  printf("Testing close\n");
-  wiringPiISRStop (IRQpin) ;
+	printf("Testing IRQ @ GPIO%d with trigger @ GPIO%d falling\n", IRQpin, OUTpin);
+	wiringPiISR (IRQpin, INT_EDGE_FALLING, &wfi) ;
+	sleep(1);
+	StartSequence (INT_EDGE_FALLING, OUTpin);
+	printf("Testing close\n");
+	wiringPiISRStop (IRQpin) ;
 
-  for (int count=0; count<2; count++) {
-    printf("Measuring duration IRQ @ GPIO%d with trigger @ GPIO%d rising\n", IRQpin, OUTpin);
-    DurationTime(INT_EDGE_RISING, OUTpin, IRQpin);
+	printf("Testing IRQ @ GPIO%d with trigger @ GPIO%d both\n", IRQpin, OUTpin);
+	wiringPiISR (IRQpin, INT_EDGE_BOTH, &wfi) ;
+	sleep(1);
+	StartSequence (INT_EDGE_BOTH, OUTpin);
+	printf("Testing close\n");
+	wiringPiISRStop (IRQpin) ;
 
-    printf("Measuring duration IRQ @ GPIO%d with trigger @ GPIO%d falling\n", IRQpin, OUTpin);
-    DurationTime(INT_EDGE_FALLING, OUTpin, IRQpin);
-  }
-  pinMode(OUTpin, INPUT);
+	for (int count=0; count<2; count++) {
+	printf("Measuring duration IRQ @ GPIO%d with trigger @ GPIO%d rising\n", IRQpin, OUTpin);
+	DurationTime(INT_EDGE_RISING, OUTpin, IRQpin);
 
-  return UnitTestState();
+	printf("Measuring duration IRQ @ GPIO%d with trigger @ GPIO%d falling\n", IRQpin, OUTpin);
+	DurationTime(INT_EDGE_FALLING, OUTpin, IRQpin);
+	}
+	pinMode(OUTpin, INPUT);
+
+	return UnitTestState();
 }
diff --git a/wiringPi/test/wpi_test.h b/wiringPi/test/wpi_test.h
index a2c3b19..d29b363 100644
--- a/wiringPi/test/wpi_test.h
+++ b/wiringPi/test/wpi_test.h
@@ -20,14 +20,14 @@ void CheckGPIO(int GPIO, int GPIOIN, int out) {
 
     int in = out;
     if (GPIOIN>=0) {
-        in  = digitalRead(GPIOIN);
+		in = digitalRead(GPIOIN);
     }
     int readback = digitalRead(GPIO);
 
     int pass = 0;
-    if (out==readback && in==out) {
-        pass = 1;
-    }
+	if (out==readback && in==out) {
+		pass = 1;
+	}
 
     if (GPIOIN>=0) {
         printf("set GPIO%02d = %d (readback %d), in GPIO%02d = %d         ", GPIO, out, readback, GPIOIN, in);
@@ -44,6 +44,11 @@ void CheckGPIO(int GPIO, int GPIOIN, int out) {
 }
 
 
+void CheckInversGPIO(int GPIO, int GPIOIN, int out) {
+	CheckGPIO(GPIO, GPIOIN, out==HIGH ? LOW : HIGH);
+}
+
+
 void digitalWriteEx(int GPIO, int GPIOIN, int mode) {
     digitalWrite(GPIO, mode);
     delayMicroseconds(5000);
diff --git a/wiringPi/wiringPi.c b/wiringPi/wiringPi.c
index 22d2010..d98b8cc 100644
--- a/wiringPi/wiringPi.c
+++ b/wiringPi/wiringPi.c
@@ -557,6 +557,27 @@ int piBoard() {
   return RaspberryPiModel<0 ? 0 : 1;
 }
 
+
+int piBoard40Pin() {
+  if (!piBoard()){
+	  // Board not detected
+	  return -1;
+  }
+  switch(RaspberryPiModel){
+	case PI_MODEL_A:
+	case PI_MODEL_B:
+		return 0;
+// PI_MODEL_CM
+// PI_MODEL_CM3
+// PI_MODEL_CM4  
+// PI_MODEL_CM4S
+//     ? guess yes
+	default: 
+		return 1;
+  }
+}
+
+
 int GetMaxPin() {
   return PI_MODEL_5 == RaspberryPiModel ? 27 : 63;
 }
diff --git a/wiringPi/wiringPi.h b/wiringPi/wiringPi.h
index 9a26b74..3938189 100644
--- a/wiringPi/wiringPi.h
+++ b/wiringPi/wiringPi.h
@@ -268,6 +268,7 @@ extern int  wiringPiSetupPiFaceForGpioProg (void) ;	// Don't use this - for gpio
 extern          int  piGpioLayout        (void) ;
 extern          int  piBoardRev          (void) ;	// Deprecated, but does the same as piGpioLayout
 extern          void piBoardId           (int *model, int *rev, int *mem, int *maker, int *overVolted) ;
+extern          int  piBoard40Pin        (void) ;                   // Interface V3.7
 extern          int  wpiPinToGpio        (int wpiPin) ;
 extern          int  physPinToGpio       (int physPin) ;
 extern          void setPadDrive         (int group, int value) ;