![](/media/cache/img/default_profile.jpg.50x50_q85.jpg)
run this here
Dependencies: Hexi_KW40Z Hexi_OLED_SSD1351
Diff: main.cpp
- Revision:
- 0:2b94f7017e4e
- Child:
- 1:b965810f9bb3
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/main.cpp Fri Apr 27 05:53:47 2018 +0000 @@ -0,0 +1,348 @@ +#include "mbed.h" +#include "Ticker.h" +#include <stdlib.h> + +InterruptIn catchChange(PTD2); +Serial pc(USBTX, USBRX); + +// software PWM using DigitalOut +DigitalOut pulse(PTA10); + +float PERIOD = 0.06f; +float DUTYCYCLE = 0.50f; + +// period and duty cycle that we'll be changing +float currentPeriod = PERIOD; +float currentDutyCycle = DUTYCYCLE; + +// period is the time between the previous rising edge +// and the current one, so recompute each time you +// encounter a rising edge +float period; +Timer t; + +// D is fraction of time that was high during the preceding interval +float D; +Timer highTime; +Timer lowTime; + +// every 10 rising edges, print T and D +int risingEdges = 0; + +// add in a thread that will do printing so it +// doesn't interfere with my measurements +EventQueue q1; +Thread t1; + +// ticker to change from low to high and one to change from high to low +Ticker lowToHigh; // low to high every period seconds +Ticker highToLow; // high to low every period + period * duty_cycle seconds + +// switch the digital signal whenever the ticker goes off +void tickerHandle() { + if (pulse.read() == 1) { + pulse.write(0); + } else { + pulse.write(1); + } +} + +void printData() { + // this does not run in the ISR + pc.printf("mbed> %i, %.3f\n\r",(int)(period*1000000.0f),D); +} + +void riseHandle() { + // recompute the period + period = t.read(); + t.reset(); + t.start(); + + // if it's the first rising edge of a 10 edge interval, + // then reset both timers + if (risingEdges == 0) { + lowTime.reset(); + highTime.reset(); + lowTime.stop(); + highTime.start(); + + // and you're in high time on the first rising edge + risingEdges++; + } + + // if it's the tenth, then store D so that someone else can + // print it out. reset the timers and rising edge count + else if (risingEdges >= 9) { + float h = highTime.read(); + float l = lowTime.read(); + D = h / (h + l); + + lowTime.reset(); + highTime.reset(); + lowTime.stop(); + highTime.start(); + + risingEdges++; + } + + // if it's rising edge 2 ... 9, then just increment and start + // the high timer and stop the low timer + else { + risingEdges++; + lowTime.stop(); + highTime.start(); + } + + // then defer the possible printf call to the other thread + if (risingEdges == 10) { + q1.call(&printData); + risingEdges = 0; + } +} + +// when you come to a falling edge, you should stop the high timer and +// start the low timer +void fallHandle() { + lowTime.start(); + highTime.stop(); +} + +void inputHandle() { + char buff[256]; + gets(buff); + + // extract out the values from the character array + int i = 0; + char p[20]; + while (buff[i] != ',') { + p[i] = buff[i]; + ++i; + } + p[i] = '\0'; + + i += 2; + int j = 0; + char dc[20]; + while (buff[i] != '\0') { + dc[j] = buff[i]; + ++i; + ++j; + } + + int T_temp = atoi(p); + float D_temp = atof(dc); + + // make the changes to the period and duty cycle as long + // as they are within range + if ((T_temp >= 1000.0f && T_temp <= 60000.0f) && + (D_temp >= 0.0f && D_temp <= 1.0f)) + { + currentPeriod = ((float)T_temp) / 1000000.0f; + currentDutyCycle = D_temp; + // set to low + pulse.write(0); + // reset the low to high ticker + lowToHigh.detach(); + lowToHigh.attach(&tickerHandle, currentPeriod); + highToLow.detach(); + // wait period * duty cycle + wait(currentPeriod * currentDutyCycle); + // reset the high to low ticker + highToLow.attach(&tickerHandle, currentPeriod); + } + + // print an error, non-blocking, if they input bad values + else { + q1.call(printf,"mbed> ERROR\r\n"); + } +} + +// main() runs in its own thread in the OS +int main() { + + // each time you see a rising edge, recompute the period + // and stop timing the low signal + catchChange.rise(&riseHandle); + catchChange.fall(&fallHandle); + + // when the user inputs something + pc.attach(&inputHandle); + + // start low + pulse.write(0); + + // ticker that goes from low to high every period seconds + lowToHigh.attach(&tickerHandle, currentPeriod); + // wait period * duty cycle + wait(currentPeriod * currentDutyCycle); + // ticker that goes from high to low every period seconds + highToLow.attach(&tickerHandle, currentPeriod); + + t1.start(callback(&q1, &EventQueue::dispatch_forever)); + + wait(osWaitForever); +} + + + + + + + + + +//#include "mbed.h" +//#include <string> +//#include <sstream> +//#include "Ticker.h" +// +// +//InterruptIn catchChange(PTD2); +//// printing from the device +//Serial pc(USBTX, USBRX); +// +//// software PWM using DigitalOut +//DigitalOut pulse(PTA10); +// +//// some defaults +//float DEFAULT_PERIOD = 0.1f; +//float DEFAULT_DUTYCYCLE = 0.5f; +//float currentPeriod; +//float currentDutyCycle; +// +//// ticker to change from low to high and one to change from high to low +//Ticker lowToHigh; +//Ticker highToLow; +// +//// every 10 rising edges, print T and D +//int risingEdges = 0; +// +//// T is time between current edge and the previous one +//int T_prev = -1; +//int T_curr = -1; +//int T; +// +//// D is fraction of time that was high during the preceding interval +//float D; +//Timer highTime; +//Timer lowTime; +// +// +//// when you come on a rising edge, you should increment the rising edges +//// and count the time as high, meaning stop the low timer and start the +//// high timer +//void riseHandle() { +// // every time, manage the time difference between the previous rising +// // edge and the one that came after it +// T_prev = T_curr; +// T_curr = (int)(highTime.read() * 1000000.0f); +// +// // if it's the first rising edge of a 10 edge interval, +// // then reset both timers +// if (risingEdges == 0) { +// lowTime.stop(); +// highTime.start(); +// lowTime.reset(); +// highTime.reset(); +// +// // and you're in high time on the first rising edge +// risingEdges++; +// } +// +// // if it's the tenth, then store D so that someone else can +// // print it out. reset the timers and rising edge count +// else if (risingEdges == 9) { +// float h = highTime.read(); +// float l = lowTime.read(); +// D = h / (h + l); +// +// T = T_curr - T_prev; +// +//// pc.printf("previous rising edge: %i, this rising edge: %i\n\r",T_prev,T_curr); +// +// lowTime.stop(); +// highTime.start(); +// lowTime.reset(); +// highTime.reset(); +// +// risingEdges++; +// } +// +// // if it's rising edge 2 ... 9, then just increment and start +// // the high timer and stop the low timer +// else { +// risingEdges++; +// lowTime.stop(); +// highTime.start(); +// } +//} +// +//// when you come to a falling edge, you should stop the high timer and +//// start the low timer +//void fallHandle() { +// lowTime.start(); +// highTime.stop(); +//} +// +//void inputHandle() { +// int T_temp; +// float D_temp; +// pc.scanf("%i, %f",&T_temp,&D_temp); +// pc.printf("read in T as %i, D as %f\r\n",T_temp,D_temp); +// +// // make the changes to the period and duty cycle as long +// // as they are within range +// if ((T_temp >= 1000 && T_temp <= 60000) && +// (D_temp >= 0.0f && D_temp <= 1.0f)) +// { +// currentPeriod = (float)T_temp / 1000000.0f; +// currentDutyCycle = D_temp; +// +// pc.printf("period is now %f, duty cycle is now %f\n\r",(float)T_temp/1000000.0f,D_temp); +// } +// +// else { +// pc.printf("mbed> ERROR\n\r"); +// } +//} +// +//void tickerHandle() { +// if (pulse.read() == 1) { +// pulse.write(0); +// } else { +// pulse.write(1); +// } +//} +// +//int main() { +// catchChange.rise(&riseHandle); +// catchChange.fall(&fallHandle); +// pc.attach(&inputHandle); +// +// currentPeriod = DEFAULT_PERIOD; +// currentDutyCycle = DEFAULT_DUTYCYCLE; +// +// // start at a low signal +// pulse.write(0); +// +// // go from low to high every period seconds +// float riseInterval = currentPeriod; +// // go from high to low every period + period*dutyCycle seconds +// float fallInterval = riseInterval + currentPeriod * currentDutyCycle; +// +// // set ticker to change signal given intervals above +// lowToHigh.attach(&tickerHandle, riseInterval); +// highToLow.attach(&tickerHandle, fallInterval); +// +// pc.printf("Starting main function!!!\n\r"); +// +// pc.printf("rise interval: %f, fall interval: %f\n\r",riseInterval,fallInterval); +// +// while (1) { +// if (risingEdges >= 10) { +// risingEdges = 0; +// pc.printf("mbed> %u, %.3f\n\r", T, D); +// } +// +// } +//}