noop din / Mbed OS ADCandticker_sample

the code for Lab3

Fork of ADCandticker_sample by William Marsh

main.cpp@3:2db0cd79282b, 2018-02-09 (annotated)

Committer:
toh2018
Date:
Fri Feb 09 21:03:44 2018 +0000
Revision:
3:2db0cd79282b
Parent:
2:f7c24790b1ad
Child:
4:8edcd6d3c39f
second commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
WilliamMarshQMUL 0:ad3cdc525b99 1
WilliamMarshQMUL 0:ad3cdc525b99 2 // LAB 3 SAMPLE PROGRAM 1
WilliamMarshQMUL 1:126dd2f5fc2d 3 // Revised for mbed 5
WilliamMarshQMUL 0:ad3cdc525b99 4
WilliamMarshQMUL 0:ad3cdc525b99 5 #include "mbed.h"
WilliamMarshQMUL 1:126dd2f5fc2d 6
WilliamMarshQMUL 0:ad3cdc525b99 7
WilliamMarshQMUL 0:ad3cdc525b99 8 Ticker tick; // Ticker for reading analog
WilliamMarshQMUL 0:ad3cdc525b99 9 AnalogIn ain(A0) ; // Analog input
toh2018 2:f7c24790b1ad 10 DigitalOut led1(D8); // Red LED
toh2018 2:f7c24790b1ad 11 DigitalOut led2(D9);
toh2018 2:f7c24790b1ad 12 DigitalOut led3(D10);
toh2018 2:f7c24790b1ad 13 DigitalOut led4(D11);
toh2018 2:f7c24790b1ad 14 DigitalOut led5(D12);
WilliamMarshQMUL 0:ad3cdc525b99 15
WilliamMarshQMUL 0:ad3cdc525b99 16 Serial pc(USBTX, USBRX); // tx, rx, for debugging
toh2018 2:f7c24790b1ad 17 DigitalIn b1(PTE1,PullUp);
WilliamMarshQMUL 0:ad3cdc525b99 18
toh2018 2:f7c24790b1ad 19 Thread pollT ; // thread to poll
toh2018 2:f7c24790b1ad 20 volatile int pressEvent = 0 ; // Variabe set by the polling thread
toh2018 2:f7c24790b1ad 21 volatile int maxvolt = 330;
toh2018 2:f7c24790b1ad 22
toh2018 3:2db0cd79282b 23 /// implement the botton here /////////////////////////////////////
toh2018 2:f7c24790b1ad 24
toh2018 2:f7c24790b1ad 25
toh2018 2:f7c24790b1ad 26 enum buttonPos { up, down, bounce }; // Button positions
toh2018 2:f7c24790b1ad 27 void polling() {
toh2018 2:f7c24790b1ad 28 buttonPos pos = up ;
toh2018 2:f7c24790b1ad 29 int bcounter = 0 ;
toh2018 2:f7c24790b1ad 30 while (true) {
toh2018 2:f7c24790b1ad 31 switch (pos) {
toh2018 2:f7c24790b1ad 32 case up :
toh2018 2:f7c24790b1ad 33 if (!b1.read()) { // now down
toh2018 2:f7c24790b1ad 34 pressEvent = 1 ; // transition occurred
toh2018 2:f7c24790b1ad 35 pos = down ;
toh2018 2:f7c24790b1ad 36 }
toh2018 2:f7c24790b1ad 37 break ;
toh2018 2:f7c24790b1ad 38 case down :
toh2018 2:f7c24790b1ad 39 if (b1 == 1) { // no longer down
toh2018 2:f7c24790b1ad 40 bcounter = 3 ; // wait four cycles
toh2018 2:f7c24790b1ad 41 pos = bounce ;
toh2018 2:f7c24790b1ad 42 }
toh2018 2:f7c24790b1ad 43 break ;
toh2018 2:f7c24790b1ad 44 case bounce :
toh2018 2:f7c24790b1ad 45 if (b1 == 0) { // down again - button has bounced
toh2018 2:f7c24790b1ad 46 pos = down ; // no event
toh2018 2:f7c24790b1ad 47 } else if (bcounter == 0) {
toh2018 2:f7c24790b1ad 48 pos = up ; // delay passed - reset to up
toh2018 2:f7c24790b1ad 49 } else {
toh2018 2:f7c24790b1ad 50 bcounter-- ; // continue waiting
toh2018 2:f7c24790b1ad 51 }
toh2018 2:f7c24790b1ad 52 break ;
toh2018 2:f7c24790b1ad 53 }
toh2018 2:f7c24790b1ad 54 Thread::wait(30);
toh2018 2:f7c24790b1ad 55 }
toh2018 2:f7c24790b1ad 56 }
toh2018 3:2db0cd79282b 57 // end the button //////////////////////////////////////////////////
toh2018 2:f7c24790b1ad 58
WilliamMarshQMUL 0:ad3cdc525b99 59 // Message type
WilliamMarshQMUL 0:ad3cdc525b99 60 typedef struct {
WilliamMarshQMUL 0:ad3cdc525b99 61 uint16_t analog; /* Analog input value */
WilliamMarshQMUL 0:ad3cdc525b99 62 } message_t;
WilliamMarshQMUL 0:ad3cdc525b99 63
WilliamMarshQMUL 0:ad3cdc525b99 64 // Mail box
WilliamMarshQMUL 0:ad3cdc525b99 65 Mail<message_t, 2> mailbox;
WilliamMarshQMUL 0:ad3cdc525b99 66
WilliamMarshQMUL 0:ad3cdc525b99 67 // Function called every 10ms to read ADC
WilliamMarshQMUL 0:ad3cdc525b99 68 // Low pass filter
WilliamMarshQMUL 0:ad3cdc525b99 69 // Every 10th value is sent to mailbox
WilliamMarshQMUL 0:ad3cdc525b99 70 volatile int samples = 0 ;
WilliamMarshQMUL 0:ad3cdc525b99 71 volatile uint16_t smoothed = 0 ;
WilliamMarshQMUL 0:ad3cdc525b99 72 void readA0() {
WilliamMarshQMUL 0:ad3cdc525b99 73 smoothed = (smoothed >> 1) + (ain.read_u16() >> 1) ;
WilliamMarshQMUL 0:ad3cdc525b99 74 samples++ ;
WilliamMarshQMUL 0:ad3cdc525b99 75 if (samples == 10) {
WilliamMarshQMUL 0:ad3cdc525b99 76 // send to thread
WilliamMarshQMUL 0:ad3cdc525b99 77 message_t *mess = mailbox.alloc() ; // may fail but does not block
WilliamMarshQMUL 0:ad3cdc525b99 78 if (mess) {
WilliamMarshQMUL 0:ad3cdc525b99 79 mess->analog = smoothed ;
WilliamMarshQMUL 0:ad3cdc525b99 80 mailbox.put(mess); // fails but does not block if full
WilliamMarshQMUL 0:ad3cdc525b99 81 }
WilliamMarshQMUL 0:ad3cdc525b99 82 samples = 0;
WilliamMarshQMUL 0:ad3cdc525b99 83 }
WilliamMarshQMUL 0:ad3cdc525b99 84 }
WilliamMarshQMUL 0:ad3cdc525b99 85
WilliamMarshQMUL 0:ad3cdc525b99 86 // Write voltage digits
WilliamMarshQMUL 0:ad3cdc525b99 87 // v Voltage as scale int, e.g. 3.30 is 330
WilliamMarshQMUL 0:ad3cdc525b99 88 void vToString(int v, char* s) {
WilliamMarshQMUL 0:ad3cdc525b99 89 s[3] = '0' + (v % 10) ;
WilliamMarshQMUL 0:ad3cdc525b99 90 v = v / 10 ;
WilliamMarshQMUL 0:ad3cdc525b99 91 s[2] = '0' + (v % 10) ;
WilliamMarshQMUL 0:ad3cdc525b99 92 v = v / 10 ;
WilliamMarshQMUL 0:ad3cdc525b99 93 s[0] = '0' + (v % 10) ;
WilliamMarshQMUL 0:ad3cdc525b99 94 }
WilliamMarshQMUL 0:ad3cdc525b99 95
WilliamMarshQMUL 0:ad3cdc525b99 96 // Main program
WilliamMarshQMUL 0:ad3cdc525b99 97 // Initialise variables
WilliamMarshQMUL 0:ad3cdc525b99 98 // Attach ISR for ticker
WilliamMarshQMUL 0:ad3cdc525b99 99 // Procss messages from mailbox
WilliamMarshQMUL 0:ad3cdc525b99 100 int main() {
WilliamMarshQMUL 0:ad3cdc525b99 101 led1 = 1 ; // turn off
toh2018 2:f7c24790b1ad 102 led2 = 1;
toh2018 2:f7c24790b1ad 103 led3 = 1;
toh2018 2:f7c24790b1ad 104 led4 = 1;
toh2018 2:f7c24790b1ad 105 led5 = 1;
WilliamMarshQMUL 0:ad3cdc525b99 106 int volts = 0 ;
toh2018 3:2db0cd79282b 107 //const int threshold = 100 ;
toh2018 2:f7c24790b1ad 108 const int threshold1 = 55 ;
toh2018 2:f7c24790b1ad 109 const int threshold2 = 110 ;
toh2018 2:f7c24790b1ad 110 const int threshold3 = 165 ;
toh2018 2:f7c24790b1ad 111 const int threshold4 = 220 ;
toh2018 2:f7c24790b1ad 112 const int threshold5 = 275 ;
WilliamMarshQMUL 0:ad3cdc525b99 113 int counter = 0 ;
WilliamMarshQMUL 0:ad3cdc525b99 114 char vstring[] = "X.XX\r\n" ;
WilliamMarshQMUL 0:ad3cdc525b99 115
WilliamMarshQMUL 0:ad3cdc525b99 116 tick.attach_us(callback(&readA0), 10000); // ticks every 10ms
WilliamMarshQMUL 0:ad3cdc525b99 117 while (true) {
WilliamMarshQMUL 0:ad3cdc525b99 118 osEvent evt = mailbox.get(); // wait for mail
WilliamMarshQMUL 0:ad3cdc525b99 119 if (evt.status == osEventMail) {
WilliamMarshQMUL 0:ad3cdc525b99 120 message_t* mess = (message_t*)evt.value.p ;
WilliamMarshQMUL 0:ad3cdc525b99 121 volts = (mess->analog * 330) / 0xffff ;
WilliamMarshQMUL 0:ad3cdc525b99 122 mailbox.free(mess) ; // free the message space
toh2018 2:f7c24790b1ad 123
toh2018 3:2db0cd79282b 124 ////press event ////////////////////////////////////
toh2018 2:f7c24790b1ad 125
toh2018 2:f7c24790b1ad 126 if(pressEvent)
toh2018 2:f7c24790b1ad 127 {
toh2018 2:f7c24790b1ad 128 pressEvent =0;
toh2018 2:f7c24790b1ad 129 maxvolt = volts;
toh2018 3:2db0cd79282b 130
toh2018 2:f7c24790b1ad 131 }
toh2018 2:f7c24790b1ad 132
toh2018 3:2db0cd79282b 133 // End of the pressEvent ////////////////////////////
toh2018 2:f7c24790b1ad 134
toh2018 2:f7c24790b1ad 135 if (volts > threshold1) led1 = 1 ; else led1 = 0 ;
toh2018 2:f7c24790b1ad 136 if (volts > threshold2) led2 = 1 ; else led2 = 0 ;
toh2018 2:f7c24790b1ad 137 if (volts > threshold3) led3 = 1 ; else led3 = 0 ;
toh2018 2:f7c24790b1ad 138 if (volts > threshold4) led4 = 1 ; else led4 = 0 ;
toh2018 2:f7c24790b1ad 139 if (volts > threshold5) led5 = 1 ; else led5 = 0 ;
WilliamMarshQMUL 0:ad3cdc525b99 140 vToString(volts, vstring) ;
WilliamMarshQMUL 0:ad3cdc525b99 141 counter++ ;
WilliamMarshQMUL 0:ad3cdc525b99 142 if (counter == 10) { // limit bandwidth of serial
WilliamMarshQMUL 0:ad3cdc525b99 143 pc.printf(vstring) ;
WilliamMarshQMUL 0:ad3cdc525b99 144 counter = 0 ;
WilliamMarshQMUL 0:ad3cdc525b99 145 }
WilliamMarshQMUL 0:ad3cdc525b99 146 }
WilliamMarshQMUL 0:ad3cdc525b99 147
WilliamMarshQMUL 0:ad3cdc525b99 148 }
WilliamMarshQMUL 0:ad3cdc525b99 149 }