Simple revolution counter with custom IRQ handler and IO macros

Dependencies:   TextLCD mbed SimpleIOMacros

Files at this revision

API Documentation at this revision

Comitter:
tlunzer
Date:
Wed Jun 01 09:36:16 2011 +0000
Commit message:
V 1.0

Changed in this revision

SimpleIOMacros.lib Show annotated file Show diff for this revision Revisions of this file
TextLCD.lib Show annotated file Show diff for this revision Revisions of this file
main.cpp Show annotated file Show diff for this revision Revisions of this file
mbed.bld Show annotated file Show diff for this revision Revisions of this file
diff -r 000000000000 -r 2352ac8d6438 SimpleIOMacros.lib
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SimpleIOMacros.lib	Wed Jun 01 09:36:16 2011 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/AjK/code/SimpleIOMacros/#cb1f38aaae0a
diff -r 000000000000 -r 2352ac8d6438 TextLCD.lib
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TextLCD.lib	Wed Jun 01 09:36:16 2011 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/tlunzer/code/TextLCD/#a7c08c5305b3
diff -r 000000000000 -r 2352ac8d6438 main.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Wed Jun 01 09:36:16 2011 +0000
@@ -0,0 +1,76 @@
+/*
+Simple revolution counter, works stable for 1 - 50000 rpm's
+Uses 1 pulse/revolution at pin 10
+*/
+#include "mbed.h"
+#include "TextLCD.h"
+#include "IOMacros.h"
+
+Ticker timer;
+Timer t;
+DigitalOut led(LED1);
+volatile float count,oldcount, revf;
+int rev;
+
+TextLCD lcd(p15, p16, p17, p18, p19, p20, TextLCD::LCD16x1);
+
+
+// Function prototype/forward declaration for ISR.
+void atint();
+
+/** EINT3_IRQHandler
+ */
+extern "C" void EINT3_IRQHandler (void) {
+
+    // The "event" is connected to pin p10 which is LPC1768 P0_1
+    // so lets trap that and ignore all other GPIO interrupts.
+    // Test for IRQ on Port0.
+    if (LPC_GPIOINT->IntStatus & 0x1) {
+        // If P0_1/p10 rises, call atint()
+        if (LPC_GPIOINT->IO0IntStatR & (1 << 1))  atint();
+    }
+
+    // Clear this and all other possible GPIO generated interrupts as they don't concern us.
+    LPC_GPIOINT->IO2IntClr = (LPC_GPIOINT->IO2IntStatR | LPC_GPIOINT->IO2IntStatF);
+    LPC_GPIOINT->IO0IntClr = (LPC_GPIOINT->IO0IntStatR | LPC_GPIOINT->IO0IntStatF);
+}
+
+void event_irq_init(void) {
+    // Use macro to set p10 as an input.
+    p10_AS_INPUT;
+    // Enable P0_1/p10 for rising edge interrupt generation.
+    LPC_GPIOINT->IO0IntEnR |= (1UL << 1);
+    // Enable the interrupt.
+    NVIC_EnableIRQ(EINT3_IRQn);
+}
+
+void atint() {
+    count = t.read();
+    t.reset();
+}
+
+void attim() {
+    LED1_TOGGLE; // Use macro instead of led =!led;
+    if (count!=oldcount) {
+        oldcount = count;
+        rev= (60/count);
+            if (rev >= 15000) // Reduce resolution to 100 rpm
+                rev = (rev/100)*100;
+            else if (rev >= 1000) // Reduce resolution to 10 rpm
+                rev = (rev/10)*10;
+        lcd.cls();
+        lcd.printf("U/m %5d ",rev);
+    }
+}
+
+int main() {
+    count = 0;
+    lcd.printf("Revolution counter",rev);
+    wait(0.5);
+    lcd.cls();
+    timer.attach(&attim,1);
+    event_irq_init();
+    t.start();
+    while (1) {
+    }
+}
\ No newline at end of file
diff -r 000000000000 -r 2352ac8d6438 mbed.bld
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed.bld	Wed Jun 01 09:36:16 2011 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_official/code/mbed/builds/63bcd7ba4912