jim hamblen
Pushbutton counter demo with debounce and a callback using interrupts
Revision 0:cc87c48aa43c, committed 2011-09-20
- Comitter:
- 4180_1
- Date:
- Tue Sep 20 14:06:28 2011 +0000
- Commit message:
Changed in this revision
diff -r 000000000000 -r cc87c48aa43c PinDetect.lib --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/PinDetect.lib Tue Sep 20 14:06:28 2011 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/AjK/code/PinDetect/#cb3afc45028b
diff -r 000000000000 -r cc87c48aa43c main.cpp
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Tue Sep 20 14:06:28 2011 +0000
@@ -0,0 +1,46 @@
+#include "mbed.h"
+#include "PinDetect.h"
+// must import Cookbook PinDetct library into project
+// URL: http://mbed.org/users/AjK/libraries/PinDetect/lkyxpw
+
+DigitalOut myled(LED1);
+DigitalOut myled2(LED2);
+DigitalOut myled3(LED3);
+DigitalOut myled4(LED4);
+
+PinDetect pb(p8);
+// SPST Pushbutton debounced count demo using interrupts and callback
+// no external PullUp resistor needed
+// Pushbutton from P8 to GND.
+// A pb hit generates an interrupt and activates the callback function
+// after the switch is debounced
+
+// Global count variable
+int volatile count=0;
+
+// Callback routine is interrupt activated by a debounced pb hit
+void pb_hit_callback (void) {
+ count++;
+ myled4 = count & 0x01;
+ myled3 = (count & 0x02)>>1;
+ myled2 = (count & 0x04)>>2;
+}
+int main() {
+
+ // Use internal pullup for pushbutton
+ pb.mode(PullUp);
+ // Delay for initial pullup to take effect
+ wait(.01);
+ // Setup Interrupt callback function for a pb hit
+ pb.attach_deasserted(&pb_hit_callback);
+ // Start sampling pb input using interrupts
+ pb.setSampleFrequency();
+
+ //Blink myled in main routine forever while responding to pb changes
+ // via interrupts that activate the callback counter function
+ while (1) {
+ myled = !myled;
+ wait(.5);
+ }
+
+}
\ No newline at end of file
diff -r 000000000000 -r cc87c48aa43c mbed.bld --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Tue Sep 20 14:06:28 2011 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/63bcd7ba4912