This project was developed and tested on Raspberry Pi 4 with GrovePi+ on Bullseye (Rasperry Pi OS 11), Node 18.19.1 and npm 10.2.4.
-
npm install node-red-contrib-iot4h-grovepi
(in /home/pi/.node-red/node_modules/) node-red-restart
See https://www.dexterindustries.com/GrovePi/engineering/port-description/
In addition to a node for each of the most common sensors, there are four “general” nodes.
- Digital Input, values: 0 or 1
- Analog Input, values: 0 to 1023
- Digital Output, values: 0 or 1
- Analog Output, values: 0 to 255
See https://nodered.org/docs/user-guide/messages
Usually, the "value" of a message is stored in its payload
field.
To make integration with other nodes easy, the payload of a sensor
message only contains its values, all additional information is stored
in other properties.
If a sensor returns multiple values (e.g. temperature and humidity),
msg.payload
is an array of these values.
In addition to that, msg.valueTypes
is an array of value type
specifications {unit: ..., name: ..., type: ...}
.
This additional information is used for displaying sensor values on the LCD and when sending datapoints to the OpenDash platform.
The name
and id
values used in the open.DASH JSON object are
stored in msg.sensorname
and msg.sensorid
.
user
is set by the "RMQ Output" node and uses the "Username" value
entered in the node configuration.
For some sensors, like the button, it might be useful to send an event only when the sensor value changes.
To do so, set the reading interval to a low value (e.g. 200ms), then connect the sensor to a "rbe" node.
This node only lets messages through if their payload has changed. It can be found at the bottom of the "Functions" section.
- Button
- Switch
- Rotary Angle
- Potentiometer
- DTH11 Temperature & Humidity
- DTH22 Temperature & Humidity
- Analog Input
- Digital Input
- Water
- Moisture
- Piezo Vibration
- Gas
- Ultrasonic Ranger
- Air Quality
- Light
- LCD RGB-Backlight
- LED
- Buzzer
- Analog Output
- Digital Output
When connecting a I2C sensor, it doesn't matter which pin is used.
If a sensor returns false
instead of a numeric value,
check if the red LED on the GrovePI board is on.
In that case, disconnect all sensors from the board, detach the GrovePI board and put it back on.
Package contents obtained in part from node-red-contrib-od-grovepi and extended with own nodes for easier access to complex functionality. The main purpose is to avoid using written code at all.
Salvaged packages for existing sensor nodes for NodeRed:
- https://github.com/memetolsen/node-red-grovepi-nodes
- https://github.com/O-Hahn/node-red-contrib-grovepi
- https://github.com/DexterInd/GrovePi/tree/master/Software/NodeJS
- https://github.com/ia-cloud/GrovePi
- https://www.npmjs.com/package/node-red-contrib-od-grovepi
- https://www.npmjs.com/package/node-red-contrib-grovepi-nodes?activeTab=code