Heater files
Dependents: LEX-Demo-Firmware-Logging LEX-Demo-Firmware-Logging
Heater.cpp@3:313711a66929, 2019-07-17 (annotated)
- Committer:
- omatthews
- Date:
- Wed Jul 17 20:46:20 2019 +0000
- Revision:
- 3:313711a66929
- Parent:
- 2:7f15386fcc90
- Child:
- 4:29ffcc7b410e
Ramp added
Who changed what in which revision?
User | Revision | Line number | New 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 float scale_factors[8]; |
omatthews | 0:4e33cc8171f4 | 14 | extern Timer timer; |
omatthews | 1:4435d407d827 | 15 | extern DigitalIn adc_busy; |
omatthews | 1:4435d407d827 | 16 | extern MODSERIAL pc; |
omatthews | 1:4435d407d827 | 17 | |
omatthews | 0:4e33cc8171f4 | 18 | |
omatthews | 0:4e33cc8171f4 | 19 | |
omatthews | 3:313711a66929 | 20 | Heater::Heater(int i_port, int v_port, DigitalOut drive, float corr_grad, float corr_int, float R_ref) |
omatthews | 3:313711a66929 | 21 | :R_ref(R_ref),i_port(i_port),v_port(v_port),drive(drive),corr_grad(corr_grad),corr_int(corr_int) {} |
omatthews | 3:313711a66929 | 22 | |
omatthews | 3:313711a66929 | 23 | float Heater::R_to_T(float R) {return R*corr_grad + corr_int;} |
omatthews | 3:313711a66929 | 24 | float Heater::T_to_R(float T) {return (T - corr_int)/corr_grad;} |
omatthews | 0:4e33cc8171f4 | 25 | |
omatthews | 0:4e33cc8171f4 | 26 | |
omatthews | 2:7f15386fcc90 | 27 | void Heater::read() |
omatthews | 0:4e33cc8171f4 | 28 | { |
omatthews | 1:4435d407d827 | 29 | //Reads R and then resets the drive back to its previous value |
omatthews | 1:4435d407d827 | 30 | int i = 0; |
omatthews | 3:313711a66929 | 31 | int drive_prev = drive; //Store previous value of drive |
omatthews | 1:4435d407d827 | 32 | drive = 1; |
omatthews | 3:313711a66929 | 33 | wait_us(MEAS_DELAY); //Wait for ADC to settle |
omatthews | 1:4435d407d827 | 34 | adc.start_conversion(ALL_CH); |
omatthews | 1:4435d407d827 | 35 | while(adc_busy == 1) |
omatthews | 1:4435d407d827 | 36 | { |
omatthews | 1:4435d407d827 | 37 | wait_us(1); |
omatthews | 1:4435d407d827 | 38 | i++; |
omatthews | 1:4435d407d827 | 39 | } |
omatthews | 3:313711a66929 | 40 | adc.read_channels(); |
omatthews | 2:7f15386fcc90 | 41 | |
omatthews | 2:7f15386fcc90 | 42 | drive = drive_prev; |
omatthews | 2:7f15386fcc90 | 43 | |
omatthews | 1:4435d407d827 | 44 | |
omatthews | 1:4435d407d827 | 45 | //pc.printf("conversion took %d us\n", i ); |
omatthews | 1:4435d407d827 | 46 | i=0; |
omatthews | 1:4435d407d827 | 47 | |
omatthews | 1:4435d407d827 | 48 | |
omatthews | 3:313711a66929 | 49 | curr = adc.read_channel_result(i_port); |
omatthews | 3:313711a66929 | 50 | v = adc.read_channel_result(v_port); |
omatthews | 3:313711a66929 | 51 | if (v<0) {pc.printf("v is %d",v);} |
omatthews | 3:313711a66929 | 52 | if (curr > 0) {R = (float)v/curr;} //Avoid dividing by 0 |
omatthews | 0:4e33cc8171f4 | 53 | } |
omatthews | 0:4e33cc8171f4 | 54 | |
omatthews | 2:7f15386fcc90 | 55 | |
omatthews | 2:7f15386fcc90 | 56 | |
omatthews | 2:7f15386fcc90 | 57 | |
omatthews | 0:4e33cc8171f4 | 58 | void Heater::hold(int hold_time) |
omatthews | 0:4e33cc8171f4 | 59 | { |
omatthews | 3:313711a66929 | 60 | //Holds the heater at R_ref for the given hold time |
omatthews | 3:313711a66929 | 61 | // in: int hold_time - is the time in ms to hold the reference |
omatthews | 3:313711a66929 | 62 | |
omatthews | 0:4e33cc8171f4 | 63 | int end_time = timer.read_ms() + hold_time; |
omatthews | 1:4435d407d827 | 64 | float R_avg = 0; |
omatthews | 1:4435d407d827 | 65 | while (timer.read_ms() < end_time) |
omatthews | 0:4e33cc8171f4 | 66 | { |
omatthews | 2:7f15386fcc90 | 67 | read(); |
omatthews | 3:313711a66929 | 68 | R_avg = ((N_ROLL_AVG-1)*R_avg + R)/N_ROLL_AVG; //Enable rolling average |
omatthews | 3:313711a66929 | 69 | if (R_avg > R_ref) |
omatthews | 0:4e33cc8171f4 | 70 | { |
omatthews | 0:4e33cc8171f4 | 71 | drive = 0; |
omatthews | 3:313711a66929 | 72 | wait_us(100); //Minimum duty cycle of 10% |
omatthews | 0:4e33cc8171f4 | 73 | } |
omatthews | 3:313711a66929 | 74 | else |
omatthews | 3:313711a66929 | 75 | { |
omatthews | 3:313711a66929 | 76 | drive = 1; |
omatthews | 3:313711a66929 | 77 | //wait_us(20); //Shorter wait time as there is no cost for checking |
omatthews | 3:313711a66929 | 78 | } |
omatthews | 3:313711a66929 | 79 | |
omatthews | 0:4e33cc8171f4 | 80 | } |
omatthews | 1:4435d407d827 | 81 | } |
omatthews | 1:4435d407d827 | 82 | |
omatthews | 0:4e33cc8171f4 | 83 | |
omatthews | 3:313711a66929 | 84 | void Heater::ramp_R(int ramp_time, float R_final, float R_start) |
omatthews | 3:313711a66929 | 85 | { |
omatthews | 3:313711a66929 | 86 | int start_time = timer.read_ms(); |
omatthews | 3:313711a66929 | 87 | int end_time = start_time + ramp_time; |
omatthews | 3:313711a66929 | 88 | float ramp_rate = (R_final - R_start)/ramp_time; |
omatthews | 3:313711a66929 | 89 | |
omatthews | 3:313711a66929 | 90 | while (int time = timer.read_ms() < end_time) |
omatthews | 3:313711a66929 | 91 | { |
omatthews | 3:313711a66929 | 92 | Set_R_ref(R_start + ramp_rate * (time - start_time)/(end_time - start_time)); |
omatthews | 3:313711a66929 | 93 | hold(1); |
omatthews | 3:313711a66929 | 94 | } |
omatthews | 3:313711a66929 | 95 | } |
omatthews | 3:313711a66929 | 96 | |
omatthews | 3:313711a66929 | 97 | |
omatthews | 3:313711a66929 | 98 | void Heater::Set_R_ref(float R) {R_ref = R;} |
omatthews | 3:313711a66929 | 99 | void Heater::Set_T_ref(float T_ref) {R_ref = T_to_R(T_ref);} |
omatthews | 0:4e33cc8171f4 | 100 | |
omatthews | 2:7f15386fcc90 | 101 | int Heater::Get_i() {return curr;} |
omatthews | 2:7f15386fcc90 | 102 | int Heater::Get_v() {return v;} |
omatthews | 2:7f15386fcc90 | 103 | |
omatthews | 0:4e33cc8171f4 | 104 | float Heater::Get_R() {return R;} |
omatthews | 3:313711a66929 | 105 | float Heater::Get_T() {return R_to_T(R);} |
omatthews | 0:4e33cc8171f4 | 106 | |
omatthews | 1:4435d407d827 | 107 | void Heater::turn_on () {drive = 1;} |
omatthews | 1:4435d407d827 | 108 | |
omatthews | 1:4435d407d827 | 109 | void Heater::turn_off () {drive = 0;} |