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Lab 3 Part 2.2
Fork of ADCandticker_sample by
main.cpp
- Committer:
- diviavad
- Date:
- 2018-02-09
- Revision:
- 4:d9666f1c135b
- Parent:
- 3:b20239a6bd91
File content as of revision 4:d9666f1c135b:
// LAB 3 SAMPLE PROGRAM 1 // Revised for mbed 5 #include "mbed.h" Ticker tick; // Ticker for reading analog AnalogIn ain(A0) ; // Analog input DigitalIn b1(D15, PullUp); //DigitalOut led1(LED_RED); // Red LED DigitalOut ledy(PTD5); DigitalOut ledb(PTA13); DigitalOut ledr(PTD0); DigitalOut ledw(PTD2); DigitalOut ledg(PTD3); volatile int pressEvent = 0 ; Serial pc(USBTX, USBRX); // tx, rx, for debugging enum buttonPos { up, down, bounce }; // Button positions void polling() { buttonPos pos = up ;//chose positing in enum int bcounter = 0 ; while (true) { switch (pos) { case up : if (!b1.read()) { // now down pressEvent = 1 ; // transition occurred pos = down ; } break ; case down : if (b1 == 1) { // no longer down bcounter = 3 ; // wait four cycles pos = bounce ; } break ; case bounce : if (b1 == 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 ; } Thread::wait(30); } } // Message type typedef struct { uint16_t analog; /* Analog input value */ } message_t; Thread pollT ; // thread to poll void buttonCallback(){ pressEvent = 1 ; } // Mail box Mail<message_t, 2> mailbox; // Function called every 10ms to read ADC // Low pass filter // Every 10th value is sent to mailbox volatile int samples = 0 ; volatile uint16_t smoothed = 0 ; void readA0() { smoothed = (smoothed >> 1) + (ain.read_u16() >> 1) ; samples++ ; if (samples == 10) { // send to thread 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 } samples = 0; } } // Write voltage digits // v Voltage as scale int, e.g. 3.30 is 330 void vToString(int v, char* s) { s[3] = '0' + (v % 10) ; v = v / 10 ; s[2] = '0' + (v % 10) ; v = v / 10 ; s[0] = '0' + (v % 10) ; } // Main program // Initialise variables // Attach ISR for ticker // Procss messages from mailbox int main() { bool max_volt = false; pollT.start(callback(polling));//start thread to check button int volts = 0 ; int threshold[6] = {55,110,165,220,275,330} ; int counter = 0 ; char vstring[] = "X.XX\r\n" ; tick.attach_us(callback(&readA0), 10000); // ticks every 10ms while (true) { if(pressEvent) { pressEvent=0; max_volt = !max_volt; } 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[0]) and (max_volt==false)){ ledy = 0; ledb = 0; ledr = 0; ledw = 0; ledg = 0; } else if(volts >=(threshold[0])&&volts <=(threshold[1] and max_volt==false)){//1.1 && volts < 1.65){ ledy = 1; ledb = 0; ledr = 0; ledw = 0; ledg = 0; } else if(volts >=(threshold[1])&&volts <=(threshold[2] && max_volt==false)){ ledy = 1; ledb = 1; ledr = 0; ledw = 0; ledg = 0; } else if(volts >=(threshold[2])&&volts <=(threshold[3]) and max_volt==false){ ledy = 1; ledb = 1; ledr = 1; ledw = 0; ledg = 0; } else if(volts >=(threshold[3])&&volts <=(threshold[4]) and max_volt==false){ ledy = 1; ledb = 1; ledr = 1; ledw = 1; ledg = 0; } else if(volts >=(threshold[4])&&volts <=(threshold[5]) and max_volt==true){ ledy = 1; ledb = 1; ledr = 1; ledw = 1; ledg = 1; } if(volts>=(threshold[5])){ max_volt=false; } else{} vToString(volts, vstring) ; counter++ ; if (counter == 10) { // limit bandwidth of serial pc.printf(vstring) ; counter = 0 ; } } } }