Revision 0:be447af0921d, committed 2011-11-25

Comitter:

daveTshave

Date:

Fri Nov 25 14:32:50 2011 +0000

Commit message:

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/counter/counter.cpp	Fri Nov 25 14:32:50 2011 +0000
@@ -0,0 +1,31 @@
+/*
+ * Based on Aaron Berk's library for a QEI (http://mbed.org/users/aberk/libraries/QEI/le4bkf), this mainly involved deleting most of the functionality
+ *
+ * Includes
+ */
+#include "counter.h"
+
+counter::counter(PinName channelA) : channelA_(channelA){
+
+    pulses_       = 0;
+    channelA_.rise(this, &counter::encode);
+    
+}
+
+void counter::reset(void) {
+
+    pulses_      = 0;
+    
+}
+
+int counter::getPulses(void) {
+
+    return pulses_;
+
+}
+
+void counter::encode(void) {
+
+    pulses_++;
+    
+}
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/counter/counter.h	Fri Nov 25 14:32:50 2011 +0000
@@ -0,0 +1,57 @@
+#ifndef counter_H
+#define counter_H
+
+/**
+ * Includes
+ */
+#include "mbed.h"
+
+/**
+ * Simple counter
+ */
+class counter {
+
+public:
+
+    
+    /**
+     * Constructor.
+     *
+     * Attaches the encode function to the rise/fall edge of
+     * channels A.
+     *
+     * @param channelA mbed pin for counter input.
+     */
+    counter(PinName channelA);
+
+    /**
+     * Reset the encoder.
+     *
+     * Sets the pulses and revolutions count to zero.
+     */
+    void reset(void);
+
+    /**
+     * Read the number of pulses recorded by the encoder.
+     *
+     * @return Number of pulses which have occured.
+     */
+    int getPulses(void);
+
+private:
+
+    /**
+     * Update the pulse count.
+     *
+     * Called on every rising edge of channels A.
+     *
+     */
+    void encode(void);
+
+    InterruptIn channelA_;
+    
+    volatile int pulses_;
+    
+};
+
+#endif /* counter_H */

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Fri Nov 25 14:32:50 2011 +0000
@@ -0,0 +1,52 @@
+#include "counter.h"
+
+//todo: implement 2k sample buffer and store results until client connects, implement real time clock
+
+Serial pc(USBTX, USBRX);
+counter SF800 (p29);
+Timer t_a, t_b;
+
+int main() {
+
+    t_a.start();
+    t_b.start();
+    int a_init_pulses = 0;
+    int b_init_pulses = 0;
+    float flowrate = 0;
+    int time_window = 10000;
+
+    bool a_b_flip_flop = true; // if true use window a
+    
+    pc.printf("\n\r*************\n\rMBED restarted\n\r*************\n");
+
+    while (1) {
+        wait(0.1);
+
+        if (a_b_flip_flop) {
+            flowrate = (float)(SF800.getPulses() - a_init_pulses)/(6000 * t_a.read_ms() / 60000);
+        } else {
+            flowrate = (float)(SF800.getPulses() - b_init_pulses)/(6000 * t_b.read_ms() / 60000);
+        }
+
+        if (t_a.read_ms() > time_window) { // switch to window B
+        
+            pc.printf("\rswitching to window B = %i pulses detected in window A\n", SF800.getPulses() - a_init_pulses);
+        
+            t_a.reset();
+            a_b_flip_flop = false;
+            a_init_pulses =  SF800.getPulses();
+        }
+        
+        if (t_a.read_ms() > time_window/2 && !a_b_flip_flop) { // switch to window A
+        
+            pc.printf("\rswitching to window A = %i pulses detected in window B\n", SF800.getPulses() - b_init_pulses);
+        
+            t_b.reset();
+            a_b_flip_flop = true;
+            b_init_pulses =  SF800.getPulses();
+        }
+
+        pc.printf("\rflowrate = %f l/min", flowrate);
+    }
+
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed.bld	Fri Nov 25 14:32:50 2011 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_official/code/mbed/builds/9114680c05da