From 7d37d158e027409072a04efc981d2fd20909fc38 Mon Sep 17 00:00:00 2001
From: mstroh76 <m.stroh76@gmail.com>
Date: Fri, 10 Jan 2025 18:58:09 +0100
Subject: [PATCH] #305 measure single operation time and toggle time

---
 wiringPi/test/wiringpi_test7_bench.c | 69 ++++++++++++++++------------
 1 file changed, 40 insertions(+), 29 deletions(-)

diff --git a/wiringPi/test/wiringpi_test7_bench.c b/wiringPi/test/wiringpi_test7_bench.c
index 7edc506..d745287 100644
--- a/wiringPi/test/wiringpi_test7_bench.c
+++ b/wiringPi/test/wiringpi_test7_bench.c
@@ -11,22 +11,24 @@
 
 
 int ToggleValue = 240000000;
-float fExpectMHzdigitalWrite = 10;
-float fExpectMHzpinMode = 4;
+float fExpectTimedigitalWrite = 1/10;
+float fExpectTimedigitalRead = 1/5;
+float fExpectTimepinMode = 1/4;
+float fWriteReadDelayFactor = 1.77;
 int GPIO = 19;
 int GPIOIN = 26;
 int RaspberryPiModel = -1;
 
 
-void ReportElaped(const char* msg, const float fExpectMHz, struct timeval t1, struct timeval t2) {
+void ReportElapedTime(const char* msg, int multiop, const float fExpectTime, struct timeval t1, struct timeval t2) {
     double elapsedTime, fTimePerOperation, fFreq;
 
 	elapsedTime = (t2.tv_sec-t1.tv_sec)+(t2.tv_usec-t1.tv_usec)/1000000.0;
-	fTimePerOperation = elapsedTime*1000000.0/ToggleValue;
-	fFreq = ToggleValue/elapsedTime/1000000.0;
-	printf("  % 9d toggle took %.3f s, Time per toggle %.3f us, Freq %.3f MHz \n",
+	fTimePerOperation = elapsedTime*1000000.0/ToggleValue/multiop;
+	fFreq = 1.0f/(fTimePerOperation*2); //ToggleValue/elapsedTime/1000000.0;
+	printf("  % 9d took %.3f s, Time per operation %.3f us (toggle Freq %.3f MHz) \n",
 	  ToggleValue, elapsedTime, fTimePerOperation, fFreq);
-    CheckSameFloat(msg, fFreq, fExpectMHz, fExpectMHz*0.2f);
+    CheckSameFloat(msg, fTimePerOperation, fExpectTime, fExpectTime*0.2f);
 }
 
 
@@ -53,14 +55,14 @@ int main (void) {
       case PI_MODEL_AP:
       case PI_MODEL_CM:
         ToggleValue /= 7; 
-        fExpectMHzdigitalWrite = 3.8; //MHz;
-        fExpectMHzpinMode = 1.5;
+        fExpectTimedigitalWrite = 1/(3.8*2); //MHz;
+        fExpectTimepinMode = 1/(1.5*2);
         break;
       case PI_MODEL_ZERO:
       case PI_MODEL_ZERO_W: //ARM=1000MHz: 4.8/2.0
         ToggleValue /= 5; 
-        fExpectMHzdigitalWrite = 4.8; //MHz;
-        fExpectMHzpinMode = 2.0;
+        fExpectTimedigitalWrite = 1/(4.8*2); //MHz;
+        fExpectTimepinMode = 1/(2.0*2);
         break;
       case PI_MODEL_2:
         ToggleValue /= 4;
@@ -78,16 +80,18 @@ int main (void) {
       case PI_MODEL_CM4:
       case PI_MODEL_CM4S:
         ToggleValue = ToggleValue; 
-        fExpectMHzdigitalWrite = 24.5; //MHz;
-        fExpectMHzpinMode = 4.1;
+        fExpectTimedigitalWrite = 1/(2*24.5); //MHz;
+        fExpectTimepinMode = 1/(2*4.1);
         break;
       case PI_MODEL_5:
         ToggleValue = ToggleValue*0.8; 
-        fExpectMHzdigitalWrite = 20.0; //MHz;
-        fExpectMHzpinMode = 2.5;
+        fExpectTimedigitalWrite = 1/(2*20.0); //MHz;
+        fExpectTimepinMode = 1/(2*2.5);
          break;
     }
 
+    fExpectTimedigitalRead = fExpectTimedigitalWrite*2;
+
 
 
 	printf("WiringPi GPIO speed test program (using GPIO %d) and toggle %d times\n", GPIO, ToggleValue);
@@ -95,40 +99,42 @@ int main (void) {
 
 	pinMode(GPIO, OUTPUT);
 
-	printf("write % 3d million times pin value ...\n", ToggleValue/1000000);
+	printf("% 3d million times digitalWrite ...\n", ToggleValue/1000000);
 	gettimeofday(&t1, NULL);
 	for (int loop=1; loop<ToggleValue; loop++) {
-		digitalWrite(GPIO, LOW);
 		digitalWrite(GPIO, HIGH);
+    digitalWrite(GPIO, LOW);
 	}
 	gettimeofday(&t2, NULL);
-  ReportElaped("GPIO digitalWrite max. frequency ", fExpectMHzdigitalWrite, t1, t2);
+  ReportElapedTime("digitalWrite", 2, fExpectTimedigitalWrite, t1, t2);
 
 	digitalWrite(GPIO, LOW);
-	pinMode(GPIO, INPUT);
+	pinMode(GPIOIN, INPUT);
 
+  ToggleValue /=2;
   printf("\n");
   printf("% 3d million times digitalRead ...\n", ToggleValue/1000000);
 	gettimeofday(&t1, NULL);
 	for (int loop=1; loop<ToggleValue; loop++) {
 		digitalRead(GPIOIN);
+    digitalRead(GPIOIN);
 	}
 	gettimeofday(&t2, NULL);
-  ReportElaped("GPIO digitalRead max. read ", fExpectMHzdigitalWrite, t1, t2);
+  ReportElapedTime("digitalRead", 2, fExpectTimedigitalRead, t1, t2);
     
-  ToggleValue /= 10;
+  ToggleValue /= 4;
   printf("\n");
-  printf("toggle % 3d million times pin mode...\n", ToggleValue/1000000);
+  printf("% 3d million times pinMode...\n", ToggleValue/1000000);
   gettimeofday(&t1, NULL);
 	for (int loop=1; loop<ToggleValue; loop++) {
 		pinMode(GPIO, OUTPUT);
-		pinMode(GPIO, INPUT);
+    pinMode(GPIOIN, INPUT);
 	}
 	gettimeofday(&t2, NULL);
-  ReportElaped("GPIO pinMode max. frequency ", fExpectMHzpinMode, t1, t2);
+  ReportElapedTime("pinMode", 2, fExpectTimepinMode, t1, t2);
 
   printf("\n");
-  printf("toggle % 3d million times pin mode and digitalWrite ..\n", ToggleValue/1000000);
+  printf("Toggle % 3d million times pinMode and digitalWrite ..\n", ToggleValue/1000000);
   gettimeofday(&t1, NULL);
 	for (int loop=1; loop<ToggleValue; loop++) {
 		pinMode(GPIO, OUTPUT);
@@ -137,19 +143,24 @@ int main (void) {
 		pinMode(GPIO, INPUT);
 	}
 	gettimeofday(&t2, NULL);
-  ReportElaped("GPIO pinMode max. frequency ", 1/(1/fExpectMHzpinMode+1/fExpectMHzdigitalWrite), t1, t2);
+  ReportElapedTime("pinMode and digitalWrite", 2, fExpectTimepinMode+fExpectTimedigitalWrite, t1, t2);
 
-  ToggleValue *= 3;
+  ToggleValue *= 1.5;
   printf("\n");
   pinMode(GPIO, OUTPUT);
-  printf("% 3d million times digitalRead and digitalWrite ..\n", ToggleValue/1000000);
+  printf("Toggle % 3d million times digitalRead and digitalWrite ..\n", ToggleValue/1000000);
   gettimeofday(&t1, NULL);
 	for (int loop=1; loop<ToggleValue; loop++) {
 		digitalWrite(GPIO, HIGH);
 		digitalRead(GPIOIN);
+  	digitalWrite(GPIO, LOW);
+		digitalRead(GPIOIN);  
 	}
 	gettimeofday(&t2, NULL);
-  ReportElaped("GPIO pinMode max. frequency ", fExpectMHzdigitalWrite/2.6, t1, t2);
+  ReportElapedTime("digitalRead and digitalWrite", 2, fExpectTimedigitalWrite+fExpectTimedigitalRead*fWriteReadDelayFactor, t1, t2);
+  double elapsedTime = (t2.tv_sec-t1.tv_sec)+(t2.tv_usec-t1.tv_usec)/1000000.0;
+  double fTimePerOperation = elapsedTime*1000000.0/ToggleValue/2;
+  CheckSameFloat("Write <=> Read delay factor", fTimePerOperation/(fExpectTimedigitalWrite+fExpectTimedigitalRead), fWriteReadDelayFactor, 0.2);
 
 	digitalWrite(GPIO, LOW);
 	pinMode(GPIO, INPUT);