From 06d9302d121d8fbe5219afb81cc439b90db39f63 Mon Sep 17 00:00:00 2001
From: mstroh76 <m.stroh76@gmail.com>
Date: Sun, 24 Mar 2024 11:08:12 +0100
Subject: [PATCH] new ISR example/test program

---
 examples/isr3.c | 169 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 169 insertions(+)
 create mode 100644 examples/isr3.c

diff --git a/examples/isr3.c b/examples/isr3.c
new file mode 100644
index 0000000..36fb7f2
--- /dev/null
+++ b/examples/isr3.c
@@ -0,0 +1,169 @@
+/*
+ * isr3.c:
+ *	Wait for Interrupt test program  WiringPi >=3.2 - ISR method
+ *
+ *
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <wiringPi.h>
+#include <wpiExtensions.h>
+#include <unistd.h>
+ #include <sys/time.h>
+
+// globalCounter:
+//	Global variable to count interrupts
+//	Should be declared volatile to make sure the compiler doesn't cache it.
+
+static volatile int globalCounter;
+volatile long long gStartTime, gEndTime;
+
+/*
+ * myInterrupt:
+ *********************************************************************************
+ */
+
+static void wfi (void) { 
+  struct timeval now;
+
+  gettimeofday(&now, 0);
+  if (0==gStartTime) {
+    gStartTime = now.tv_sec*1000000LL + now.tv_usec;
+  } else {
+    gEndTime = now.tv_sec*1000000LL + now.tv_usec;
+  }
+  globalCounter++;
+}
+
+/*
+ *********************************************************************************
+ * main
+ *********************************************************************************
+ */
+
+double StartSequence (int Enge, int OUTpin) {
+  int expected;
+  double timeExpected;
+
+  gStartTime = 0;
+  gEndTime = 0;
+  globalCounter = 0;
+  printf("Start\n");
+  digitalWrite(OUTpin, HIGH); 
+  delay(200);
+  digitalWrite(OUTpin, LOW);
+  delay(100); 
+  digitalWrite(OUTpin, HIGH); 
+  delay(200);
+  digitalWrite(OUTpin, LOW);
+  delay(100);
+  printf("Stop\n");
+  int globalCounterCopy = globalCounter; 
+
+  if (INT_EDGE_BOTH == Enge) {
+    expected = 4;  
+    timeExpected = 500;
+  } else {
+    expected = 2;  
+    timeExpected = 300;
+  }
+
+  if(globalCounter==expected) {
+    double fTime = (gEndTime - gStartTime) / 1000000.0;
+    printf("IRQ worked %g sec (~%gs expected)\n\n", fTime, timeExpected/1000.0);
+    return fTime;
+  } else {
+    printf("IRQ not worked got %d iterations (%d exprected)\n\n", globalCounterCopy, expected);
+    return 0;
+  }
+}
+
+
+double DurationTime(int Enge, int OUTpin, int IRQpin) {
+  struct timeval now;
+  double fTime = 0.0;
+
+  gStartTime = 0;
+  gEndTime = 0;
+  globalCounter = 0;
+  printf("Start\n");
+
+  if (INT_EDGE_RISING == Enge) {
+    digitalWrite(OUTpin, LOW); 
+    wiringPiISR (IRQpin, INT_EDGE_RISING, &wfi) ;
+    sleep(1);
+    gettimeofday(&now, 0);
+    gStartTime = now.tv_sec*1000000LL + now.tv_usec;
+    digitalWrite(OUTpin, HIGH);  
+    delay(20);
+    digitalWrite(OUTpin, LOW);  
+   } else if (INT_EDGE_FALLING == Enge) {
+    digitalWrite(OUTpin, HIGH); 
+    wiringPiISR (IRQpin, INT_EDGE_FALLING, &wfi) ;
+    sleep(1);
+    gettimeofday(&now, 0);
+    gStartTime = now.tv_sec*1000000LL + now.tv_usec;    
+    digitalWrite(OUTpin, LOW);  
+  }
+
+  sleep(1);
+  fTime = (gEndTime - gStartTime);
+  printf("IRQ detect time %g usec\n\n", fTime);
+  wiringPiISRStop (IRQpin) ;
+
+  return fTime;
+}
+
+int main (void)
+{
+  const int IRQpin = 22 ;
+  const int OUTpin = 25 ;
+  int major, minor;
+
+  wiringPiVersion(&major, &minor);
+
+  printf("\nISR test (WiringPi %d.%d)\n", major, minor);
+
+  wiringPiSetupGpio() ;
+
+  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 falling\n", IRQpin, OUTpin);
+  wiringPiISR (IRQpin, INT_EDGE_FALLING, &wfi) ;
+  sleep(1);
+  StartSequence (INT_EDGE_FALLING, OUTpin);
+  printf("Testing close\n");
+  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) ;
+
+  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("Measuring duration IRQ @ GPIO%d with trigger @ GPIO%d falling\n", IRQpin, OUTpin);
+    DurationTime(INT_EDGE_FALLING, OUTpin, IRQpin);
+  }
+  pinMode(OUTpin, INPUT);
+
+  return 0 ;
+}