Add Some Prototype Code for the SG112A/B CO2 Sensor

This commit is contained in:
seiichiro 2021-02-02 21:12:31 +01:00
parent 899dc743f2
commit 0180a0342f
4 changed files with 83 additions and 10 deletions

View file

@ -1,22 +1,77 @@
#include <Arduino.h>
#include "SG112A.h"
void GA112A(void) {
SG112A::SG112A(void) {
Serial.begin(9600);
Serial.setTimeout(READ_TIMEOUT);
delay(5000);
write(CMD_GET_PPM);
read();
}
void SG112A::getSensorData(lora_data &loradata) {
write(CMD_GET_PPM);
delay(50);
uint8_t byteLen = read();
if (byteLen > 0) {
switch(buffer[3]) {
case 0x15:
loradata.ppm = (buffer[5]*256) + buffer[4];
break;
}
}
}
uint16_t SG112A::getPPM(void) {
void SG112A::write(byte cmd) {
uint8_t _cmd[6] = {0xAA, 0x55, cmd, 0x00, 0x00, 0x00};
uint16_t crc = crc16(_cmd, 4);
_cmd[4] = (uint8_t)(crc & 0xFF);
_cmd[5] = (uint8_t)(crc >> 8);
while (Serial.available() > 0) Serial.read();
Serial.write(_cmd, 6);
Serial.flush();
}
void SG112A::sendCmd(uint8_t *cmd, uint8_t len) {
uint8_t SG112A::read() {
uint8_t ret = 0;
zeroBuffer();
if (Serial.available() > 0) {
ret = Serial.readBytes(buffer, SER_BUF_LEN);
}
uint16_t SG112A::crc16(uint8_t *cmd, uint8_t len){
if (buffer[0] != 0xBB && buffer[1] != 0x66)
ret = 0;
// TODO: Do CRC Check Here
return ret;
}
void SG112A::zeroBuffer() {
for (int i=0; i < SER_BUF_LEN; i++)
buffer[i] = 0x00;
}
uint16_t SG112A::crc16(uint8_t *cmd, int len){
uint16_t ret = 0xffff;
uint16_t polynomial = 0xa001;
int shift = 0x0;
int i = 0;
for (i = len - 1; i >= 0 ; i-- ){
uint16_t code = ( uint16_t )( cmd [ len -1 - i ] & 0xff );
ret = ret^code;
shift = 0x0;
while ( shift <= 7 ){
if ( ret & 0x1 ) {
ret = ret >> 1;
ret = ret^polynomial ;
} else {
ret = ret >> 1;
}
shift++;
}
}
return ret;
}

View file

@ -6,11 +6,23 @@ struct lora_data {
int16_t ppm;
} __attribute__ ((packed));
#define READ_TIMEOUT 500
#define SER_BUF_LEN 16
#define CMD_GET_VER 0x10
#define CMD_GET_SER 0x12
#define CMD_GET_PPM 0x14
class SG112A {
private:
void sendCmd(uint8_t *cmd, uint8_t len);
uint16_t crc16(uint8_t *cmd, uint8_t len);
uint8_t buffer[SER_BUF_LEN];
void write(byte cmd);
uint8_t read();
void zeroBuffer(void);
uint16_t crc16(uint8_t *cmd, int len);
uint16_t getPPM(void);
public:
SG112A(void);
void getSensorData(lora_data &loradata);

View file

@ -3,11 +3,14 @@
#define LED_PIN PIN_PA7
// Enable Serial Debugging. Parameters for the Serial Port are 115200
// Please be aware that the SG112A/B CO2 Sensor uses the HW-UART, so
// Serial Debug Output is not available with this Sensor.
// #define DEBUG
// Define which Sensor is installed
#define HAS_BME280
// #define HAS_SHT21
// #define HAS_SG112A
// #define HAS_NO_SENSOR
// How many minutes to sleep between Measuring/Sending

View file

@ -35,6 +35,9 @@ void blink(uint8_t num) {
struct lora_data {
uint8_t bat;
} __attribute ((packed));
#elif defined HAS_SG112A
#include <SG112A.h>
SG112A sensor;
#elif defined HAS_BME280
#include <BME280.h>
BME280 sensor;
@ -68,7 +71,7 @@ const lmic_pinmap lmic_pins = {
};
// List of unused Pins - will be disabled for Power Saving
#ifdef DEBUG
#if defined DEBUG || defined HAS_SG112A
const int disabledPins[] = {PIN_PB5, PIN_PB4, PIN_PB1, PIN_PB0, PIN_PC3, PIN_PC2, PIN_PC1, PIN_PC0};
#else
const int disabledPins[] = {PIN_PB5, PIN_PB4, PIN_PB3, PIN_PB2, PIN_PB1, PIN_PB0, PIN_PC3, PIN_PC2, PIN_PC1, PIN_PC0};