hydroponic-controller/include/ec.h

189 lines
4.7 KiB
C

#ifndef _EC_H_
#define _EC_H_
#include <Arduino.h>
float ecEC_ADS_CHANNEL_mean=0;
bool ec_flag_measurement_available=false;
#define EC_PIN_RELAY_PROBE 27
#define EC_PIN_RELAY_RANGEMSB 25
#define EC_PIN_RELAY_RANGELSB 26
//#define EC_PIN_ADC 4
#define EC_ADS_CHANNEL 0
#define EC_PIN_FREQ 5
#define EC_PWM_CH 0
#define EC_RESOLUTION 8
#define EC_FREQUENCY 5000
#define EC_ARRAY_SIZE 64
uint16_t ec_array_range00[EC_ARRAY_SIZE]; //00=NC,NC = highest value
uint16_t ec_array_range01[EC_ARRAY_SIZE];
uint16_t ec_array_range10[EC_ARRAY_SIZE];
uint16_t ec_array_range11[EC_ARRAY_SIZE]; //11= NO,NO = lowest value
uint16_t ec_array_pos=EC_ARRAY_SIZE*4;
unsigned long last_measurement_ec=0;
#define EC_MEASUREMENT_INTERVAL 10000 //complete filtered measurement every x ms
//One filtered measurement takes EC_READ_INTERVAL*EC_ARRAY_SIZE*4
#define EC_READ_INTERVAL 2 //interval of reading adc value inside a measurement
#define EC_RELAY_SWITCH_SETTLETIME 500 //time until voltage of ec circuit has settled
const uint16_t ec_centerADCvalue=1909; //adc value when probe resistance is equal to the range resistor (mean of both)
unsigned long ec_last_change_relay=0; //millis of last relay change
enum ECState{IDLE,MEASURE};
ECState ecstate=IDLE;
float adc_range00;
float adc_range01;
float adc_range10;
float adc_range11;
bool ec_measurementReady();
void ec_startMeasurement();
void ec_setRange(uint8_t range);
void ec_connectProbe(bool);
void ec_releaseRelay();
void ec_setup() {
//pinMode(EC_PIN_ADC,INPUT);
ledcSetup(EC_PWM_CH, EC_FREQUENCY, EC_RESOLUTION);
ledcAttachPin(EC_PIN_FREQ, EC_PWM_CH);
ledcWrite(EC_PWM_CH, 127); //50% duty cycle
pinMode(EC_PIN_RELAY_PROBE,OUTPUT); //LOW=Calibration/idle, HIGH=Probe connected
pinMode(EC_PIN_RELAY_RANGELSB,OUTPUT); //LOW=NC, HIGH=NO
pinMode(EC_PIN_RELAY_RANGEMSB,OUTPUT); //LOW=NC, HIGH=NO
ec_releaseRelay();
}
void ec_loop(unsigned long loopmillis) {
static unsigned long last_read_ec=0;
switch (ecstate) {
case IDLE:
if (loopmillis>last_measurement_ec+EC_MEASUREMENT_INTERVAL && ecstate==IDLE) { //start measurement if idle
last_measurement_ec=loopmillis;
ec_startMeasurement();
ec_connectProbe(true);
ecstate=MEASURE;
}
break;
case MEASURE:
if (ec_measurementReady()) {
ec_releaseRelay();
adc_range00=getMean(ec_array_range00,EC_ARRAY_SIZE); //good for low conductivity/high resistance
adc_range01=getMean(ec_array_range01,EC_ARRAY_SIZE);
adc_range10=getMean(ec_array_range10,EC_ARRAY_SIZE);
adc_range11=getMean(ec_array_range11,EC_ARRAY_SIZE); //good for high conductivity/low resistance
//ec_mean=0; //TODO select right range of all readings
ec_flag_measurement_available=true;
ecstate=IDLE;
}
break;
}
if (loopmillis>last_read_ec+EC_READ_INTERVAL && ec_array_pos/4<EC_ARRAY_SIZE) { //take reading into array if measurement running
last_read_ec=loopmillis;
//flag_print= ec_array_pos==EC_ARRAY_SIZE;
//ec_array_pos%=EC_ARRAY_SIZE;
ec_setRange(ec_array_pos/EC_ARRAY_SIZE);
if (loopmillis>ec_last_change_relay+EC_RELAY_SWITCH_SETTLETIME) { //values have settled
//uint16_t value=analogRead(EC_PIN_ADC);
uint16_t value = ADS.readADC(EC_ADS_CHANNEL);
switch (ec_array_pos/EC_ARRAY_SIZE){ //low range
case 0:
ec_array_range00[ec_array_pos%EC_ARRAY_SIZE]=value;
break;
case 1:
ec_array_range01[ec_array_pos%EC_ARRAY_SIZE]=value;
break;
case 2:
ec_array_range10[ec_array_pos%EC_ARRAY_SIZE]=value;
break;
case 3:
ec_array_range11[ec_array_pos%EC_ARRAY_SIZE]=value;
break;
}
ec_array_pos++;
}
}
}
void ec_startMeasurement() {
ec_array_pos=0;
}
bool ec_measurementReady(){
if (ec_array_pos/EC_ARRAY_SIZE>=4) { //reached end of both arrays
return true;
}else{
return false;
}
}
void ec_setRange(uint8_t range) {
//range low means low resistor value -> NO -> relay High
uint8_t crange=digitalRead(EC_PIN_RELAY_RANGELSB)+2*digitalRead(EC_PIN_RELAY_RANGEMSB);
if (crange!=range) { //write only if different
digitalWrite(EC_PIN_RELAY_RANGELSB,range%2);
digitalWrite(EC_PIN_RELAY_RANGEMSB,range/2);
ec_last_change_relay=millis();
}
}
void ec_connectProbe(bool relay) {
bool val=digitalRead(EC_PIN_RELAY_PROBE);
if (val!=relay) { //write only if different
digitalWrite(EC_PIN_RELAY_PROBE,relay);
ec_last_change_relay=millis();
}
}
void ec_releaseRelay() {
digitalWrite(EC_PIN_RELAY_PROBE,LOW);
digitalWrite(EC_PIN_RELAY_RANGEMSB,LOW);
digitalWrite(EC_PIN_RELAY_RANGELSB,LOW);
ec_last_change_relay=millis();
}
#endif