You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
234 lines
6.3 KiB
234 lines
6.3 KiB
// -----------------------------------------------------------------------------
|
|
// SenseAir S8 CO2 Sensor
|
|
// Uses SoftwareSerial library
|
|
// Contribution by Yonsm Guo
|
|
// -----------------------------------------------------------------------------
|
|
|
|
#if SENSOR_SUPPORT && SENSEAIR_SUPPORT
|
|
|
|
#pragma once
|
|
|
|
#include <Arduino.h>
|
|
#include <SoftwareSerial.h>
|
|
|
|
#include "BaseSensor.h"
|
|
|
|
|
|
// SenseAir sensor utils
|
|
class SenseAir
|
|
{
|
|
protected:
|
|
SoftwareSerial *_serial; // Should initialized by child class
|
|
|
|
public:
|
|
int sendCommand(byte command[]) {
|
|
byte recv_buf[7] = {0xff};
|
|
byte data_buf[2] = {0xff};
|
|
long value = -1;
|
|
|
|
_serial->write(command, 8); //Send the byte array
|
|
delay(50);
|
|
|
|
// Read answer from sensor
|
|
int ByteCounter = 0;
|
|
while(_serial->available()) {
|
|
recv_buf[ByteCounter] = _serial->read();
|
|
ByteCounter++;
|
|
}
|
|
|
|
data_buf[0] = recv_buf[3];
|
|
data_buf[1] = recv_buf[4];
|
|
value = (data_buf[0] << 8) | (data_buf[1]);
|
|
|
|
return value;
|
|
}
|
|
|
|
int readCo2(void) {
|
|
int co2 = 0;
|
|
byte frame[8] = {0};
|
|
buildFrame(0xFE, 0x04, 0x03, 1, frame);
|
|
co2 = sendCommand(frame);
|
|
return co2;
|
|
}
|
|
|
|
private:
|
|
// Compute the MODBUS RTU CRC
|
|
static unsigned int modRTU_CRC(byte buf[], int len, byte checkSum[2]) {
|
|
unsigned int crc = 0xFFFF;
|
|
|
|
for (int pos = 0; pos < len; pos++) {
|
|
crc ^= (unsigned int)buf[pos]; // XOR byte into least sig. byte of crc
|
|
|
|
for (int i = 8; i != 0; i--) { // Loop over each bit
|
|
if ((crc & 0x0001) != 0) { // If the LSB is set
|
|
crc >>= 1; // Shift right and XOR 0xA001
|
|
crc ^= 0xA001;
|
|
}
|
|
else // Else LSB is not set
|
|
crc >>= 1; // Just shift right
|
|
}
|
|
}
|
|
// Note, this number has low and high bytes swapped, so use it accordingly (or swap bytes)
|
|
checkSum[1] = (byte)((crc >> 8) & 0xFF);
|
|
checkSum[0] = (byte)(crc & 0xFF);
|
|
return crc;
|
|
}
|
|
|
|
static int getBitOfInt(int reg, int pos) {
|
|
// Create a mask
|
|
int mask = 0x01 << pos;
|
|
|
|
// Mask the status register
|
|
int masked_register = mask & reg;
|
|
|
|
// Shift the result of masked register back to position 0
|
|
int result = masked_register >> pos;
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
static void buildFrame(byte slaveAddress,
|
|
byte functionCode,
|
|
short startAddress,
|
|
short numberOfRegisters,
|
|
byte frame[8]) {
|
|
frame[0] = slaveAddress;
|
|
frame[1] = functionCode;
|
|
frame[2] = (byte)(startAddress >> 8);
|
|
frame[3] = (byte)(startAddress);
|
|
frame[4] = (byte)(numberOfRegisters >> 8);
|
|
frame[5] = (byte)(numberOfRegisters);
|
|
// CRC-calculation
|
|
byte checkSum[2] = {0};
|
|
modRTU_CRC(frame, 6, checkSum);
|
|
frame[6] = checkSum[0];
|
|
frame[7] = checkSum[1];
|
|
}
|
|
};
|
|
|
|
//
|
|
class SenseAirSensor : public BaseSensor, SenseAir {
|
|
|
|
public:
|
|
|
|
// ---------------------------------------------------------------------
|
|
// Public
|
|
// ---------------------------------------------------------------------
|
|
|
|
SenseAirSensor(): BaseSensor() {
|
|
_count = 1;
|
|
_co2 = 0;
|
|
_lastCo2 = 0;
|
|
_serial = NULL;
|
|
_sensor_id = SENSOR_SENSEAIR_ID;
|
|
}
|
|
|
|
~SenseAirSensor() {
|
|
if (_serial) delete _serial;
|
|
_serial = NULL;
|
|
}
|
|
|
|
void setRX(unsigned char pin_rx) {
|
|
if (_pin_rx == pin_rx) return;
|
|
_pin_rx = pin_rx;
|
|
_dirty = true;
|
|
}
|
|
|
|
void setTX(unsigned char pin_tx) {
|
|
if (_pin_tx == pin_tx) return;
|
|
_pin_tx = pin_tx;
|
|
_dirty = true;
|
|
}
|
|
|
|
// ---------------------------------------------------------------------
|
|
|
|
unsigned char getRX() {
|
|
return _pin_rx;
|
|
}
|
|
|
|
unsigned char getTX() {
|
|
return _pin_tx;
|
|
}
|
|
|
|
// ---------------------------------------------------------------------
|
|
// Sensor API
|
|
// ---------------------------------------------------------------------
|
|
|
|
// Initialization method, must be idempotent
|
|
void begin() {
|
|
|
|
if (!_dirty) return;
|
|
|
|
if (_serial) delete _serial;
|
|
|
|
_serial = new SoftwareSerial(_pin_rx, _pin_tx, false, 64);
|
|
_serial->enableIntTx(false);
|
|
_serial->begin(9600);
|
|
_serial->enableRx(true);
|
|
|
|
_startTime = 0;
|
|
_ready = true;
|
|
_dirty = false;
|
|
}
|
|
|
|
// Descriptive name of the sensor
|
|
String description() {
|
|
char buffer[28];
|
|
snprintf(buffer, sizeof(buffer), "SenseAir S8 @ SwSerial(%u,%u)", _pin_rx, _pin_tx);
|
|
return String(buffer);
|
|
}
|
|
|
|
// Descriptive name of the slot # index
|
|
String slot(unsigned char index) {
|
|
return description();
|
|
}
|
|
|
|
// Address of the sensor (it could be the GPIO or I2C address)
|
|
String address(unsigned char index) {
|
|
char buffer[6];
|
|
snprintf(buffer, sizeof(buffer), "%u:%u", _pin_rx, _pin_tx);
|
|
return String(buffer);
|
|
}
|
|
|
|
// Type for slot # index
|
|
unsigned char type(unsigned char index) {
|
|
return MAGNITUDE_CO2;
|
|
}
|
|
|
|
void pre() {
|
|
|
|
if (millis() - _startTime < 20000) {
|
|
_error = SENSOR_ERROR_WARM_UP;
|
|
return;
|
|
}
|
|
|
|
unsigned int co2 = readCo2();
|
|
if (co2 >= 5000 || co2 < 100)
|
|
{
|
|
_co2 = _lastCo2;
|
|
_error = SENSOR_ERROR_OUT_OF_RANGE;
|
|
}
|
|
else
|
|
{
|
|
_co2 = (co2 > _lastCo2 + 2000) ? _lastCo2 : co2;
|
|
_lastCo2 = co2;
|
|
_error = SENSOR_ERROR_OK;
|
|
}
|
|
}
|
|
|
|
// Current value for slot # index
|
|
double value(unsigned char index) {
|
|
return _co2;
|
|
}
|
|
|
|
protected:
|
|
unsigned int _pin_rx;
|
|
unsigned int _pin_tx;
|
|
unsigned long _startTime;
|
|
unsigned int _co2;
|
|
unsigned int _lastCo2;
|
|
};
|
|
|
|
|
|
#endif // SENSOR_SUPPORT && SENSEAIR_SUPPORT
|