The Technology Partnership / Heater_V2

Heater for threaded program

Dependents:   LEX_Threaded_Programming_V3

Heater.cpp@30:055d856f05b5, 2019-08-29 (annotated)

Committer:
omatthews
Date:
Thu Aug 29 16:07:56 2019 +0000
Revision:
30:055d856f05b5
Parent:
28:88d9088ddb8a
Child:
31:7c6f05326c4d
Edits made, but errors in temperature logging

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 26:f6c98b05ee85 12 extern Timer timer;
omatthews 0:4e33cc8171f4 13 extern ADS8568_ADC adc;
omatthews 1:4435d407d827 14 extern DigitalIn adc_busy;
omatthews 30:055d856f05b5 15 extern MODSERIAL pc;
omatthews 20:2d34a03ae57e 16 extern DigitalOut led_0;
omatthews 26:f6c98b05ee85 17 extern FastPWM drive_1;
omatthews 26:f6c98b05ee85 18 extern FastPWM drive_2;
omatthews 26:f6c98b05ee85 19 extern FastPWM guard_1;
omatthews 26:f6c98b05ee85 20 extern FastPWM guard_2;
omatthews 30:055d856f05b5 21
omatthews 30:055d856f05b5 22 Heater::Heater(const int i_port, const int v_port, FastPWM * drive, FastPWM * guard, const memspcr_ThermalConfiguration & thermal)
omatthews 30:055d856f05b5 23 :thermal(thermal), i_port(i_port), v_port(v_port), drive(drive), guard(guard)
omatthews 30:055d856f05b5 24 {
omatthews 30:055d856f05b5 25 drive->prescaler(1);
omatthews 30:055d856f05b5 26 guard->prescaler(1);
omatthews 30:055d856f05b5 27 drive->period_ticks(1000);
omatthews 30:055d856f05b5 28 guard->period_ticks(1000);
omatthews 30:055d856f05b5 29 }
omatthews 30:055d856f05b5 30
omatthews 7:59ece353eea2 31
omatthews 0:4e33cc8171f4 32
omatthews 26:f6c98b05ee85 33 void Heater::log()const
omatthews 11:785a0329f802 34 {
omatthews 18:f5d26d3d532f 35 //Prints the current state to the terminal
omatthews 17:0bfed0e96927 36 pc.printf("%d,%f,%f,%f,%f,%f\n",timer.read_ms(),R_ref,R,error,error_integrated,drive->read());
omatthews 11:785a0329f802 37 }
omatthews 0:4e33cc8171f4 38
omatthews 2:7f15386fcc90 39 void Heater::read()
omatthews 0:4e33cc8171f4 40 {
omatthews 1:4435d407d827 41 //Reads R and then resets the drive back to its previous value
omatthews 30:055d856f05b5 42 int i = 0;
omatthews 17:0bfed0e96927 43 double drive_prev = drive->read(); //Store previous value of drive
omatthews 18:f5d26d3d532f 44 *drive = 1.0f; //Turn the driver on for the measurement
omatthews 26:f6c98b05ee85 45 wait_us(thermal.adc_settling_time_us); //Wait for ADC to settle
omatthews 25:09a315a59956 46 adc.start_conversion(15);
omatthews 25:09a315a59956 47
omatthews 18:f5d26d3d532f 48 //Incremental back off until ADC is free
omatthews 30:055d856f05b5 49 while(adc_busy == 1) {
omatthews 30:055d856f05b5 50 wait_us(1);
omatthews 30:055d856f05b5 51 i++;
omatthews 30:055d856f05b5 52 }
omatthews 25:09a315a59956 53
omatthews 20:2d34a03ae57e 54 drive->write(0); //Reset the duty cycle back to what it was
omatthews 18:f5d26d3d532f 55
omatthews 18:f5d26d3d532f 56 //Get voltage, current and R values from the ADC conversion
omatthews 0:4e33cc8171f4 57 adc.read_channels();
omatthews 7:59ece353eea2 58 curr = adc.read_channel_result(i_port);
omatthews 7:59ece353eea2 59 v = adc.read_channel_result(v_port);
omatthews 30:055d856f05b5 60
omatthews 30:055d856f05b5 61 if (curr > 0) {
omatthews 30:055d856f05b5 62 R = (float)v/curr; //Avoid dividing by 0
omatthews 30:055d856f05b5 63 }
omatthews 12:8a048f111140 64
omatthews 18:f5d26d3d532f 65 //Get error values
omatthews 30:055d856f05b5 66
omatthews 17:0bfed0e96927 67 error = R_ref - R;
omatthews 30:055d856f05b5 68
omatthews 25:09a315a59956 69 //Only allow positive integrated errors and limit change in integrated error
omatthews 30:055d856f05b5 70 //to help avoid integral windup
omatthews 30:055d856f05b5 71
omatthews 30:055d856f05b5 72 if (abs(error) > WIND_UP_LIMIT) {error = error * WIND_UP_LIMIT / abs(error);}
omatthews 25:09a315a59956 73
omatthews 30:055d856f05b5 74 error_integrated += error;
omatthews 30:055d856f05b5 75
omatthews 30:055d856f05b5 76 if (error_integrated < 0.0) {
omatthews 30:055d856f05b5 77 error_integrated = 0.0;
omatthews 30:055d856f05b5 78 }
omatthews 0:4e33cc8171f4 79 }
omatthews 0:4e33cc8171f4 80
omatthews 2:7f15386fcc90 81
omatthews 2:7f15386fcc90 82
omatthews 2:7f15386fcc90 83
omatthews 25:09a315a59956 84 void Heater::update()
omatthews 7:59ece353eea2 85 {
omatthews 25:09a315a59956 86 //Update PWM from setpoint and resistance
omatthews 26:f6c98b05ee85 87 drive->write((double) (thermal.adc_settling_time_us * (error + error_integrated/thermal.pid_integral_time)));
omatthews 26:f6c98b05ee85 88 guard->write((double) (thermal.adc_settling_time_us * thermal.guard_drive_ratio * (error + error_integrated/thermal.pid_integral_time)));
omatthews 7:59ece353eea2 89 }
omatthews 18:f5d26d3d532f 90
omatthews 18:f5d26d3d532f 91
omatthews 30:055d856f05b5 92 void Heater::Set_ref(float R)
omatthews 19:fccdd7127f94 93 {
omatthews 19:fccdd7127f94 94 R_ref = R;
omatthews 19:fccdd7127f94 95 }
omatthews 30:055d856f05b5 96 void Heater::Set_D(float D)
omatthews 30:055d856f05b5 97 {
omatthews 25:09a315a59956 98 drive->write(D);
omatthews 26:f6c98b05ee85 99 guard->write(D*thermal.guard_drive_ratio);
omatthews 30:055d856f05b5 100 }
omatthews 0:4e33cc8171f4 101
omatthews 30:055d856f05b5 102 int Heater::Get_i() const
omatthews 30:055d856f05b5 103 {
omatthews 30:055d856f05b5 104 return curr;
omatthews 30:055d856f05b5 105 }
omatthews 30:055d856f05b5 106 int Heater::Get_v() const
omatthews 30:055d856f05b5 107 {
omatthews 30:055d856f05b5 108 return v;
omatthews 30:055d856f05b5 109 }
omatthews 2:7f15386fcc90 110
omatthews 30:055d856f05b5 111 float Heater::Get_R() const
omatthews 30:055d856f05b5 112 {
omatthews 30:055d856f05b5 113 return R;
omatthews 30:055d856f05b5 114 }
omatthews 0:4e33cc8171f4 115
omatthews 30:055d856f05b5 116 void Heater::turn_on ()
omatthews 19:fccdd7127f94 117 {
omatthews 19:fccdd7127f94 118 *drive = 1;
omatthews 26:f6c98b05ee85 119 *guard = thermal.guard_drive_ratio;
omatthews 19:fccdd7127f94 120 }
omatthews 1:4435d407d827 121
omatthews 30:055d856f05b5 122 void Heater::turn_off ()
omatthews 19:fccdd7127f94 123 {
omatthews 19:fccdd7127f94 124 *drive = 0;
omatthews 19:fccdd7127f94 125 *guard = 0;
omatthews 19:fccdd7127f94 126 }