Daniel Camuti
/
CoupledTankSystem
Mbed code for the lab
main.cpp
- Committer:
- DCamuti
- Date:
- 2015-09-24
- Revision:
- 0:108062801773
- Child:
- 1:abca5455262a
File content as of revision 0:108062801773:
#include "mbed.h" // APIs Serial pc(USBTX, USBRX); // tx, rx for serial USB interface to pc SPI spi_max1270(p5, p6, p7); SPI spi(p5, p6, p7); DigitalOut max1270_cs(p8); //MAX1270 ADC CS DigitalOut mot1_ph1(p21); //DigitalOut mot1_ph2(p22); PwmOut mot_en1(p23); LocalFileSystem local("local"); // Create the local filesystem under the name "local" int read_max1270(int chan, int range, int bipol){ int cword=0x80; //set the start bit spi_max1270.frequency(10000000); spi_max1270.format(8, 0); // 8 data bits, CPOL0, and CPHA0 (datasheet Digital Interface) cword |= (chan << 4); //shift channel cword |= (range << 3); cword |= (bipol << 2); max1270_cs = 0; spi_max1270.write(cword); wait_us(15); //15us spi_max1270.format(12, 3); int result = spi_max1270.write(0); max1270_cs = 1; spi_max1270.format(8, 0); return result; } float read_max1270_volts(int chan, int range, int bipol){ float rangevolts=0.0; float volts=0.0; int adc_res; //read the ADC converter adc_res = read_max1270(chan, range, bipol) & 0xFFF; //Determine the voltage range if(range) //RNG bit rangevolts=10.0; else rangevolts=5.0; //bi-polar input range if(bipol){ //BIP is set, input is +/- if(adc_res < 0x800){ //if result was positive volts = ((float)adc_res/0x7FF) * rangevolts; } else{ //result was negative volts = -(-((float)adc_res/0x7FF) * rangevolts) - (rangevolts * 2.0); } } else{ //input is positive polarity only volts = ((float)adc_res/0xFFF) * rangevolts; } return volts; } float Tank1,Tank2,dt; float Ts = 1.0; // Sampling period 1/Ts Hz // Arrays for data storage float etime[200]; float t1v[200]; float t2v[200]; float dcp[200]; Timer t; float cntr; float dc; int k; int main () { pc.baud(921600); // Establish baud rate mot_en1.period_us(50); // Set PWM length to 50 us max1270_cs = 1; // Activate A/D cntr = 0.0; // cntr used to keep track of sample period and elpased time // initialize data vectors for(k=0;k<100;k++) { etime[k] = 0.0; t1v[k] = 0.0; t2v[k] = 0.0; dcp[k] = 0.0; } k = 0; // Reset index counter pc.printf("Time Tank1 Tank2 DC \n\r"); while(cntr*Ts <= 60) { t.start(); // start measuring comp time // Read pressure sensors Tank1 = read_max1270_volts(1, 1, 1); // in volt Tank2 = read_max1270_volts(0, 1, 1); // Select pump duty cycle, start time, and end time if (cntr*Ts <= 10) { //start time dc = 0.0; } else if (cntr*Ts <= 20) { //end time // //dc = -0.80; // duty cycle (must be negative) //dc=-0.60; //dc=-0.65; //dc=-0.70; //dc=-0.75; dc = -0.0; } else { dc = 0.0; } if(dc > 0.0){ //mot1_ph2 = 0; mot1_ph1 = 1; mot_en1 = dc; } else if(dc <=0.0){ mot1_ph1 = 0; //mot1_ph2 = 1; mot_en1 = abs(dc);} // Log data etime[k] = cntr*Ts; t1v[k] = Tank1; t2v[k] = Tank2; dcp[k] = -dc; k++; t.stop(); // end measuring comp time dt = Ts-t.read(); //pc.printf("%5.2f %5.2f %5.2f %5.2f \n\r",cntr*Ts,Tank1,Tank2,dc); pc.printf("%5.2f %5.2f %5.2f %5.2f \n\r",cntr*Ts,Tank1,Tank2,dc); t.reset(); cntr=cntr+1; wait(dt); // wait to ensure sampling period set by Ts }//while //mot1_ph2 = 0; mot_en1 = 0.0; }//main