I am trying to interface a Grove CO2 Sensor with my Electron. I followed the tutorial here by @peekay123 and am running into the following issues:
1. Serial1 unavailable:
In setup, I’ve added a check to see if communication between the Electron and the sensor has been established using a
while(!Serial1.available()){ Serial.println("Waiting for connection");} Serial.println("Connected!");
Serial1 remains unavailable forever until I touch (barely nudge) the TX-RX wires between the sensor and the Electron. I am certain there are no loose connections. I know this because once the Serial1 becomes available after nudging the connection wires, it goes back to “Unavailable” when I merely reset the board without disturbing anything. I’m having to do this each time!
2. Checksum Fails:
According to the datasheet for the grove CO2 sensor:
In code,
(1 + (0xFF ^ (byte)(data[1] + data[2] + data[3] + data[4] + data[5] + data[6] + data[7]))) != data[8]) - This check is always failing!
Here is the output I get:
3. Wrong CO2 Values:
I’m guessing this is due to obvious reasons ( 1 & 2).
Setup Background:
- Electron is connected to my Laptop and a 3.7V LiPo
- Sensor - Electron mapping: Vcc -> Vin (>=4.5V) , GND -> GND, RX -> TX, TX -> RX
- For gas and calibration:
const unsigned char cmd_get_sensor[] = { 0xff, 0x01, 0x86, 0x00, 0x00, 0x00, 0x00, 0x00, 0x79}; - Serial.begin(9600); Serial1.begin(9600); [ tried Serial.begin(115200); too - no change in result]
Much appreciate the help!