Diff: main.cpp
- Revision:
- 5:f7c980ba6e08
- Parent:
- 4:ebd00f94455a
--- a/main.cpp Thu Jan 31 13:53:15 2019 +0000
+++ b/main.cpp Thu Feb 14 22:53:14 2019 +0000
@@ -1,46 +1,89 @@
-
-// LAB 3 SAMPLE PROGRAM 1
-// Revised for mbed 5
-// Revised to replace Ticker with event queue and thread
-
#include "mbed.h"
+#define state0 0
+#define state1 1
+#define state2 2
+#define state3 3
+#define state4 4
+#define state5 5
AnalogIn ain(A0) ; // Analog input
DigitalOut led1(LED_RED); // Red LED
-EventQueue queue; // creates an event queue, to call read ADC
+DigitalOut externalLed1(D2);
+DigitalOut externalLed2(D3);
+DigitalOut externalLed3(D4);
+DigitalOut externalLed4(D5);
+DigitalOut externalLed5(D6);
-Serial pc(USBTX, USBRX); // tx, rx, for debugging
+DigitalIn externalButton(PTD0);
+
+EventQueue queue; // creates an event queue, to call read ADC
+
+Serial pc(USBTX, USBRX); // tx, rx, for debugging
// This thread runs the event queue
Thread eventThread ;
// Message type
typedef struct {
- uint16_t analog; /* Analog input value */
+ uint16_t analog; // // Analog input value
+ uint16_t pressEventOccured; // Callibration Check for a button press */
} message_t;
// Mail box
-Mail<message_t, 2> mailbox;
+Mail<message_t, 3> mailbox;
// Function called every 10ms to read ADC
// Average using a low pass filter
// Every 10th value is sent to mailbox
+
volatile int samples = 0 ;
volatile uint16_t smoothed = 0 ;
+volatile int pressEvent = 0 ; // Variable set by the polling thread
+enum buttonPos { up, down, bounce }; // Button positions
+volatile buttonPos pos = up ;
+volatile int bcounter = 0 ;
void readA0() {
+
+ switch (pos) {
+ case up :
+ if (!externalButton.read()) { // now down
+ pressEvent = 1 ; // transition occurred
+ pos = down ;
+ }
+ break ;
+ case down :
+ if (externalButton == 1) { // no longer down
+ bcounter = 3 ; // wait four cycles
+ pos = bounce ;
+ }
+ break ;
+ case bounce :
+ if (externalButton == 0) { // down again - button has bounced
+ pos = down ; // no event
+ } else if (bcounter == 0) {
+ pos = up ; // delay passed - reset to up
+ } else {
+ bcounter-- ; // continue waiting
+ }
+ break ;
+ }
+
smoothed = (smoothed >> 1) + (ain.read_u16() >> 1) ;
- samples++ ;
+ samples++ ;
+
if (samples == 10) {
// send to thread
- message_t *mess = mailbox.alloc() ; // may fail but does not block
+ message_t *mess = mailbox.alloc() ; // may fail but does not block
if (mess) {
mess->analog = smoothed ;
- mailbox.put(mess); // fails but does not block if full
+ mess->pressEventOccured = pressEvent ; // Callibration
+ pressEvent = 0;
+ mailbox.put(mess); // fails but does not block if full
}
samples = 0;
- }
+ }
}
// Write voltage digits
@@ -57,32 +100,102 @@
// Initialise variables
// Attach ISR for ticker
// Procss messages from mailbox
+
int main() {
led1 = 1 ; // turn off
int volts = 0 ;
- const int threshold = 100 ;
+ int threshold[6] = {0,0,0,0,0,0};
+ unsigned int systemState = 0;
int counter = 0 ;
char vstring[] = "X.XX\r\n" ;
-
+
// Start the event queue
eventThread.start(callback(&queue, &EventQueue::dispatch_forever));
-
+
// call the readA0 function every 10ms
queue.call_every(10, readA0) ;
while (true) {
+
osEvent evt = mailbox.get(); // wait for mail
+
if (evt.status == osEventMail) {
message_t* mess = (message_t*)evt.value.p ;
volts = (mess->analog * 330) / 0xffff ;
- mailbox.free(mess) ; // free the message space
- if (volts > threshold) led1 = 0 ; else led1 = 1 ;
+ if(mess->pressEventOccured == 1) { // Check if callibration needed
+ for (int i=0; i<6; i++) {
+ threshold[i] = (i*volts)/6 ; // Setting new thresholds according to new callibration valued
+ }
+ }
+ mailbox.free(mess) ; // free the message space
+ }
+
+ if (volts>=threshold[0] && volts<threshold[1])
+ systemState = state0;
+ else if (volts>=threshold[1] && volts<threshold[2])
+ systemState = state1;
+ else if (volts>=threshold[2] && volts<threshold[3])
+ systemState = state2;
+ else if (volts>=threshold[3] && volts<threshold[4])
+ systemState = state3;
+ else if (volts>=threshold[4] && volts<threshold[5])
+ systemState = state4;
+ else if (volts>=threshold[5])
+ systemState = state5;
+
vToString(volts, vstring) ;
counter++ ;
- if (counter == 10) { // limit bandwidth of serial
- pc.printf(vstring) ;
+ if (counter == 10) { // limit bandwidth of serial
counter = 0 ;
+ pc.printf(vstring);
+ pc.putc('\n');
+ pc.putc('\r');
}
+
+ switch(systemState) {
+ case state0:
+ externalLed1.write(0);
+ externalLed2.write(0);
+ externalLed3.write(0);
+ externalLed4.write(0);
+ externalLed5.write(0);
+ break;
+ case state1:
+ externalLed1.write(1);
+ externalLed2.write(0);
+ externalLed3.write(0);
+ externalLed4.write(0);
+ externalLed5.write(0);
+ break;
+ case state2:
+ externalLed1.write(1);
+ externalLed2.write(1);
+ externalLed3.write(0);
+ externalLed4.write(0);
+ externalLed5.write(0);
+ break;
+ case state3:
+ externalLed1.write(1);
+ externalLed2.write(1);
+ externalLed3.write(1);
+ externalLed4.write(0);
+ externalLed5.write(0);
+ break;
+ case state4:
+ externalLed1.write(1);
+ externalLed2.write(1);
+ externalLed3.write(1);
+ externalLed4.write(1);
+ externalLed5.write(0);
+ break;
+ case state5:
+ externalLed1.write(1);
+ externalLed2.write(1);
+ externalLed3.write(1);
+ externalLed4.write(1);
+ externalLed5.write(1);
+ break;
}
}
-}
+ }
+