Ollie Matthews / Heater

Heater for threaded program

Dependents:   LEX_Threaded_Programming

Heater.cpp@25:09a315a59956, 2019-08-19 (annotated)

Committer:
omatthews
Date:
Mon Aug 19 07:55:38 2019 +0000
Revision:
25:09a315a59956
Parent:
23:947850bbf325
Child:
26:f6c98b05ee85
10/08/2019

Who changed what in which revision?

UserRevisionLine numberNew contents of line
omatthews 0:4e33cc8171f4 1 /*------------------------------------------------------------------------------
omatthews 0:4e33cc8171f4 2 Library code file for interface to Heater
omatthews 0:4e33cc8171f4 3 Date: 16/07/2018
omatthews 0:4e33cc8171f4 4
omatthews 0:4e33cc8171f4 5
omatthews 0:4e33cc8171f4 6 ------------------------------------------------------------------------------*/
omatthews 1:4435d407d827 7 #include "mbed.h"
omatthews 1:4435d407d827 8 #include "MODSERIAL.h"
omatthews 0:4e33cc8171f4 9 #include "Heater.h"
omatthews 0:4e33cc8171f4 10 #include "ADS8568_ADC.h"
omatthews 0:4e33cc8171f4 11
omatthews 0:4e33cc8171f4 12 extern ADS8568_ADC adc;
omatthews 0:4e33cc8171f4 13 extern Timer timer;
omatthews 1:4435d407d827 14 extern DigitalIn adc_busy;
omatthews 1:4435d407d827 15 extern MODSERIAL pc;
omatthews 20:2d34a03ae57e 16 extern DigitalOut led_0;
omatthews 0:4e33cc8171f4 17
omatthews 0:4e33cc8171f4 18
omatthews 19:fccdd7127f94 19 Heater::Heater(const int i_port, const int v_port, FastPWM * drive, FastPWM * guard, const float corr_grad, const float corr_int, float R_ref)
omatthews 19:fccdd7127f94 20 :R_ref(R_ref),i_port(i_port),v_port(v_port),drive(drive),guard(guard),corr_grad(corr_grad),corr_int(corr_int) {}
omatthews 7:59ece353eea2 21
omatthews 0:4e33cc8171f4 22
omatthews 18:f5d26d3d532f 23 void Heater::output()const
omatthews 11:785a0329f802 24 {
omatthews 18:f5d26d3d532f 25 //Prints the current state to the terminal
omatthews 17:0bfed0e96927 26 pc.printf("%d,%f,%f,%f,%f,%f\n",timer.read_ms(),R_ref,R,error,error_integrated,drive->read());
omatthews 11:785a0329f802 27 }
omatthews 0:4e33cc8171f4 28
omatthews 2:7f15386fcc90 29 void Heater::read()
omatthews 0:4e33cc8171f4 30 {
omatthews 1:4435d407d827 31 //Reads R and then resets the drive back to its previous value
omatthews 25:09a315a59956 32
omatthews 1:4435d407d827 33 int i = 0;
omatthews 18:f5d26d3d532f 34 //float error_prev = error;
omatthews 17:0bfed0e96927 35
omatthews 17:0bfed0e96927 36 double drive_prev = drive->read(); //Store previous value of drive
omatthews 18:f5d26d3d532f 37 *drive = 1.0f; //Turn the driver on for the measurement
omatthews 7:59ece353eea2 38 wait_us(MEAS_DELAY); //Wait for ADC to settle
omatthews 25:09a315a59956 39
omatthews 25:09a315a59956 40 adc.start_conversion(15);
omatthews 25:09a315a59956 41
omatthews 18:f5d26d3d532f 42 //Incremental back off until ADC is free
omatthews 1:4435d407d827 43 while(adc_busy == 1)
omatthews 1:4435d407d827 44 {
omatthews 1:4435d407d827 45 wait_us(1);
omatthews 1:4435d407d827 46 i++;
omatthews 18:f5d26d3d532f 47 }
omatthews 25:09a315a59956 48
omatthews 20:2d34a03ae57e 49 drive->write(0); //Reset the duty cycle back to what it was
omatthews 18:f5d26d3d532f 50
omatthews 18:f5d26d3d532f 51 //Get voltage, current and R values from the ADC conversion
omatthews 0:4e33cc8171f4 52 adc.read_channels();
omatthews 7:59ece353eea2 53 curr = adc.read_channel_result(i_port);
omatthews 7:59ece353eea2 54 v = adc.read_channel_result(v_port);
omatthews 18:f5d26d3d532f 55
omatthews 17:0bfed0e96927 56 if (curr > 0) {R = (float)v/curr;} //Avoid dividing by 0
omatthews 12:8a048f111140 57
omatthews 18:f5d26d3d532f 58 //Get error values
omatthews 18:f5d26d3d532f 59
omatthews 17:0bfed0e96927 60 error = R_ref - R;
omatthews 14:f266bf960b8d 61
omatthews 25:09a315a59956 62 //Only allow positive integrated errors and limit change in integrated error
omatthews 25:09a315a59956 63 //to help avoid integral windup
omatthews 25:09a315a59956 64
omatthews 20:2d34a03ae57e 65 if (abs(error) < WIND_UP_LIMIT) {error_integrated += error;}
omatthews 23:947850bbf325 66 if (error_integrated < 0.0) {error_integrated = 0.0;}
omatthews 20:2d34a03ae57e 67
omatthews 0:4e33cc8171f4 68 }
omatthews 0:4e33cc8171f4 69
omatthews 2:7f15386fcc90 70
omatthews 2:7f15386fcc90 71
omatthews 2:7f15386fcc90 72
omatthews 25:09a315a59956 73 void Heater::update()
omatthews 7:59ece353eea2 74 {
omatthews 25:09a315a59956 75 //Update PWM from setpoint and resistance
omatthews 25:09a315a59956 76 read();
omatthews 25:09a315a59956 77 drive->write((double) (Kp * (error + error_integrated/Ti)));
omatthews 25:09a315a59956 78 guard->write((double) (Kp * GUARD_PWM_RATIO * (error + error_integrated/Ti)));
omatthews 25:09a315a59956 79 log_count++;
omatthews 25:09a315a59956 80 if (log_count >= LOG_LIM)
omatthews 7:59ece353eea2 81 {
omatthews 25:09a315a59956 82 log_count = 0;
omatthews 25:09a315a59956 83 output();
omatthews 7:59ece353eea2 84 }
omatthews 25:09a315a59956 85
omatthews 7:59ece353eea2 86 }
omatthews 18:f5d26d3d532f 87
omatthews 18:f5d26d3d532f 88
omatthews 18:f5d26d3d532f 89
omatthews 25:09a315a59956 90 void Heater::Set_ref(float R)
omatthews 19:fccdd7127f94 91 {
omatthews 19:fccdd7127f94 92 R_ref = R;
omatthews 19:fccdd7127f94 93 }
omatthews 25:09a315a59956 94 void Heater::Set_D(float D) {
omatthews 25:09a315a59956 95 drive->write(D);
omatthews 25:09a315a59956 96 guard->write(D*GUARD_PWM_RATIO);
omatthews 25:09a315a59956 97 }
omatthews 0:4e33cc8171f4 98
omatthews 18:f5d26d3d532f 99 int Heater::Get_i() const {return curr;}
omatthews 18:f5d26d3d532f 100 int Heater::Get_v() const {return v;}
omatthews 2:7f15386fcc90 101
omatthews 18:f5d26d3d532f 102 float Heater::Get_R() const {return R;}
omatthews 0:4e33cc8171f4 103
omatthews 19:fccdd7127f94 104 void Heater::turn_on ()
omatthews 19:fccdd7127f94 105 {
omatthews 19:fccdd7127f94 106 *drive = 1;
omatthews 19:fccdd7127f94 107 *guard = GUARD_PWM_RATIO;
omatthews 19:fccdd7127f94 108 }
omatthews 1:4435d407d827 109
omatthews 19:fccdd7127f94 110 void Heater::turn_off ()
omatthews 19:fccdd7127f94 111 {
omatthews 19:fccdd7127f94 112 *drive = 0;
omatthews 19:fccdd7127f94 113 *guard = 0;
omatthews 19:fccdd7127f94 114 }