Node-RED node for reading measurements from Sensirion SCD40 and SCD41, the CO2, temperature, and humidity sensors.
Uses scd4x-node.
Find the scd4x
node in the sensor
category in the palette, and use in your flow.
The node replaces the message payload with an object containing the measured values:
{
co2Concentration: <number>,
temperature: <number>,
relativeHumidity: <number>
}
The SCD4x must be in periodic measurement mode and a measurement must be available when triggering this node.
The permission to read the I2C bus device (e.g. /dev/i2c-1
) is required.
When starting the Node-RED container, use these options:
--device /dev/i2c-1
– point to the I2C device to which the SCD4x is connected--group-add <id of i2c group>
– make the container process run as a member of the i2c
groupFor example:
docker run -d \
-p 1880:1880 \
-v /home/pi/.node-red:/data \
--device /dev/i2c-1 \
--group-add 998 \
--name nodered \
nodered/node-red