Initial Commit

2012-07-10 13:37:06 +01:00
commit 2c13e6148d
21 changed files with 3578 additions and 0 deletions
--- a/examples/speed.c
+++ b/examples/speed.c
@@ -0,0 +1,103 @@
+
+/*
+ * speed.c:
+ *	Simple program to measure the speed of the various GPIO
+ *	access mechanisms.
+ */
+
+#include <wiringPi.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+
+#define	FAST_COUNT	10000000
+#define	SLOW_COUNT	 1000000
+
+
+int main (void)
+{
+  int i ;
+  uint32_t start, end, count, sum, perSec ;
+
+  printf ("Raspberry Pi wiringPi speed test program\n") ;
+
+// Start the standard way
+
+  if (wiringPiSetup () == -1)
+    exit (1) ;
+
+  printf ("Native wiringPi method: (%8d iterations)\n", FAST_COUNT) ;
+
+  pinMode (0, OUTPUT) ;
+
+  sum = 0 ;
+  for (i = 0 ; i < 3 ; ++i)
+  {
+    printf ("  Pass: %d: ", i) ;
+    fflush (stdout) ;
+
+    start = millis () ;
+    for (count = 0 ; count < FAST_COUNT ; ++count)
+      digitalWrite (0, 1) ;
+    end = millis () ;
+    printf (" %8dmS\n", end - start) ;
+    sum += (end - start) ;
+  }
+  digitalWrite (0, 0) ;
+  printf ("   Average: %8dmS", sum / 3) ;
+  perSec = (int)(double)FAST_COUNT / (double)((double)sum / 3.0) * 1000.0 ;
+  printf (": %6d/sec\n", perSec) ;
+
+
+  printf ("Native GPIO method: (%8d iterations)\n", FAST_COUNT) ;
+
+  wiringPiGpioMode (WPI_MODE_GPIO) ;
+
+  pinMode (17, OUTPUT) ;
+
+  sum = 0 ;
+  for (i = 0 ; i < 3 ; ++i)
+  {
+    printf ("  Pass: %d: ", i) ;
+    fflush (stdout) ;
+
+    start = millis () ;
+    for (count = 0 ; count < 10000000 ; ++count)
+      digitalWrite (17, 1) ;
+    end = millis () ;
+    printf (" %8dmS\n", end - start) ;
+    sum += (end - start) ;
+  }
+  digitalWrite (17, 0) ;
+  printf ("   Average: %8dmS", sum / 3) ;
+  perSec = (int)(double)FAST_COUNT / (double)((double)sum / 3.0) * 1000.0 ;
+  printf (": %6d/sec\n", perSec) ;
+
+
+// Switch to SYS mode:
+
+  wiringPiSetupSys () ;
+
+  printf ("/sys/class/gpio method: (%8d iterations)\n", SLOW_COUNT) ;
+
+  sum = 0 ;
+  for (i = 0 ; i < 3 ; ++i)
+  {
+    printf ("  Pass: %d: ", i) ;
+    fflush (stdout) ;
+
+    start = millis () ;
+    for (count = 0 ; count < SLOW_COUNT ; ++count)
+      digitalWrite (17, 1) ;
+    end = millis () ;
+    printf (" %8dmS\n", end - start) ;
+    sum += (end - start) ;
+  }
+  digitalWrite (17, 0) ;
+  printf ("   Average: %8dmS", sum / 3) ;
+  perSec = (int)(double)SLOW_COUNT / (double)((double)sum / 3.0) * 1000.0 ;
+  printf (": %6d/sec\n", perSec) ;
+
+  return 0 ;
+}