raspi read gpio

sys/raspi_gpio/read_button/Makefile

@@ -0,0 +1,15 @@
+
+CFLAGS = -O -I../hal -I../../../csrc -DU8X8_USE_PINS -ffunction-sections -fdata-sections
+LDFLAGS = -Wl,--gc-sections
+
+SRC = $(wildcard *.c) $(wildcard ../hal/*.c) $(wildcard ../../../csrc/*.c)
+
+OBJ = $(SRC:.c=.o)
+
+
+main: $(OBJ) 
+	$(CC) $(CFLAGS) $(LDFLAGS) $(OBJ) -o main
+
+clean:	
+	-rm $(OBJ) main
+

sys/raspi_gpio/read_button/main.c

@@ -0,0 +1,135 @@
+/*
+
+  main.c
+
+  raspberry pi zero GPIO read test
+
+  For speedup run this example as root, either wis
+    sudo ./main
+  or by setting the superuser bit:
+    sudo chown root:root ./main
+    sudo chmod u+s ./main
+
+*/
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <signal.h>
+#include "bcm2835.h"
+#include "raspi_gpio_hal.h"
+
+void sigtermhandler(int x)
+{
+  puts("SIGTERM");
+  bcm2835_close();
+  exit(0);
+}
+
+void siginthandler(int x)
+{
+  puts("SIGINT");
+  bcm2835_close();
+  exit(0);
+}
+
+
+#define BUTTON_STATE_NOT_PRESSED 0
+#define BUTTON_STATE_HIGH_DETECT 1
+#define BUTTON_STATE_HIGH_WAIT 2
+#define BUTTON_STATE_LOW_DELAY 3
+
+
+struct button_struct
+{
+  int state;
+  int delay;
+  uint8_t pin;
+};
+typedef struct button_struct button_t;
+#define BUTTON_DELAY_HIGH 2
+#define BUTTON_DELAY_LOW 2
+
+#define BUTTON_CNT 2
+button_t button_list[BUTTON_CNT];
+
+int button_init(void)
+{
+  int i;
+  for( i = 0; i < BUTTON_CNT; i++ )
+  {
+    bcm2835_gpio_fsel(button_list[i].pin, BCM2835_GPIO_FSEL_INPT);
+  }
+}
+
+int button_get_event(void)
+{
+  int button_value = -1;
+  int i;
+  for( i = 0; i < BUTTON_CNT; i++ )
+  {
+    switch(button_list[i].state)
+    {
+      case BUTTON_STATE_NOT_PRESSED:
+        button_list[i].delay = 0;
+        if ( bcm2835_gpio_lev(button_list[i].pin) != 0 )
+          button_list[i].state = BUTTON_STATE_HIGH_DETECT;
+        break;
+      case BUTTON_STATE_HIGH_DETECT:
+        if ( bcm2835_gpio_lev(button_list[i].pin) == 0 )
+        {
+          button_list[i].delay = 0;
+          button_list[i].state = BUTTON_STATE_LOW_DELAY;
+        }
+        button_list[i].delay++;
+        if ( button_list[i].delay >= BUTTON_DELAY_HIGH )
+        {
+          button_value = i;
+          button_list[i].state = BUTTON_STATE_HIGH_WAIT;
+        }
+        break;
+      case BUTTON_STATE_HIGH_WAIT:
+        if ( bcm2835_gpio_lev(button_list[i].pin) == 0 )
+        {
+          button_list[i].delay = 0;
+          button_list[i].state = BUTTON_STATE_LOW_DELAY;
+        }
+        break;
+      case BUTTON_STATE_LOW_DELAY:
+        button_list[i].delay++;
+        if ( button_list[i].delay >= BUTTON_DELAY_LOW )
+          button_list[i].state = BUTTON_STATE_NOT_PRESSED;
+        break;
+    }
+  }
+  return button_value;
+}
+
+int main(void)
+{
+  int i = 0;
+  int b = -1;
+  int pins[4] = { 12, 13, 16, 17 };
+
+  if (!bcm2835_init())
+    exit(1);
+
+  signal(SIGTERM, sigtermhandler);
+  signal(SIGINT, siginthandler);
+
+  atexit((void (*) (void))bcm2835_close);
+
+  button_list[0].pin = 12;
+  button_list[1].pin = 16;
+  
+  button_init();
+  for( ;; )
+  {
+    b = button_get_event();
+    if ( b >= 0 )
+      printf("Button %d\n", b);
+  }
+  
+  
+    //delaynanoseconds(500000000UL);
+    
+}

sys/raspi_gpio/read_test/main.c

@@ -22,34 +22,58 @@ void sigtermhandler(int x)
 {
   puts("SIGTERM");
   bcm2835_close();
+  exit(0);
+}
+
+void siginthandler(int x)
+{
+  puts("SIGINT");
+  bcm2835_close();
+  exit(0);
 }
 
 
 int main(void)
 {
+  int i = 0;
+  int pins[4] = { 12, 13, 16, 17 };
 
   if (!bcm2835_init())
     exit(1);
 
   signal(SIGTERM, sigtermhandler);
+  signal(SIGINT, siginthandler);
 
   atexit((void (*) (void))bcm2835_close);
 
-  bcm2835_gpio_fsel(12, BCM2835_GPIO_FSEL_INPT);
-  bcm2835_gpio_fsel(13, BCM2835_GPIO_FSEL_INPT);
-  bcm2835_gpio_fsel(16, BCM2835_GPIO_FSEL_INPT);
-  bcm2835_gpio_fsel(17, BCM2835_GPIO_FSEL_INPT);
-  
+  for( i = 0; i < sizeof(pins)/sizeof(*pins); i++ )
+  {
+    bcm2835_gpio_fsel(pins[i], BCM2835_GPIO_FSEL_INPT);
+    
+    //bcm2835_gpio_hen(pins[i]);  // high level detect
+  }
   for(;;)
   {
     
-    delaynanoseconds(1000000UL);
+    delaynanoseconds(500000000UL);
     
-    printf("%d: %d  ", 12, bcm2835_gpio_lev(12));
-    printf("%d: %d  ", 13, bcm2835_gpio_lev(13));
-    printf("%d: %d  ", 16, bcm2835_gpio_lev(16));
-    printf("%d: %d  ", 17, bcm2835_gpio_lev(17));
+    printf("%07d  ", i);
+    for( i = 0; i < sizeof(pins)/sizeof(*pins); i++ )
+    {
+      printf("%d: %d  ", pins[i], bcm2835_gpio_lev(pins[i]));
+    }
     puts("");
     
+    /*
+    for( i = 0; i < sizeof(pins)/sizeof(*pins); i++ )
+    {
+      if ( bcm2835_gpio_eds(pins[i]) )  // event detected
+      {
+        bcm2835_gpio_set_eds(pins[i]);  // clear the event
+        printf("Event: %d\n", pins[i]);
+      }
+    }
+    */
+    i++;
   }
 }