A Python MQTT client to control a Pimoroni MOTE pHAT
Start by updating / upgrading your installation (Optional)
sudo apt-get update
sudo apt-get upgrade
Install the motephat library
curl https://get.pimoroni.com/motephat | bash
Next, install other pre-requisit packages
pip install paho-mqtt simplejson
Next, clone the motephat-mqtt repository (I'll assume to /home/pi/)
git clone https://github.com/circuitbeard/motephat-mqtt.git
Next, update the IP address of the MQTT broker and the topic to connect to
sudo nano motephat-mqtt/motephat-mqtt.py
>>> client.subscribe('YOUR TOPIC')
>>> client.connect('YOUR BROKER IP', 1883, 60)
Next, make sure job.sh is executable
sudo chmod +x motephat-mqtt/job.sh
Next, setup a service to start once a network is available (taken from here)
sudo systemctl edit --force --full motephat-mqtt.service
[Unit]
Description=A MOTE pHAT MQTT Client Service
Wants=network-online.target
After=network-online.target
[Service]
Type=simple
WorkingDirectory=/home/pi/motephat-mqtt
ExecStart=/home/pi/motephat-mqtt/job.sh
[Install]
WantedBy=multi-user.target
sudo systemctl enable motephat-mqtt.service
sudo systemctl start motephat-mqtt.service
The MQTT client supports several commands, all expressed through JSON payloads. For individual commands a single command object should be sent, however you can send multiple commands by sending an array of command objects.
Clear one, multiple or all channels
{
'cmd': 'clear'
}
{
'cmd': 'clear',
'channel': 0
}
{
'cmd': 'clear',
'channels': [0,3]
}
Control the global brightness level
{
'cmd': 'brightness',
'brightness': 0.5
}
Fill one, multiple or all pixels
{
'cmd': 'fill',
'color': 'FF0000'
}
{
'cmd': 'fill',
'channel': 0,
'color': 'FF0000'
}
{
'cmd': 'fill',
'channels': [0,3],
'color': 'FF0000'
}
{
'cmd': 'fill',
'channel': 0,
'pixel': 3,
'color': 'FF0000'
}
{
'cmd': 'fill',
'channel': 0,
'pixels': [0,2,5,7,9],
'color': 'FF0000'
}
{
'cmd': 'fill',
'channels': [0,3],
'pixels': [0,2,5,7,9],
'color': 'FF0000'
}
For all fill commands, colours can be expressed in multiple ways
- 'FF0000' - Standard hex
- 'FF0000CC' - Hex + brightness
- [255,0,0] - Standard RGB
- [255,0,0, 150] - RGB + brightness
In addition to the colour formats, fill commands can also accept multiple colours at once (except where targeting a single pixel).
{
'cmd': 'fill',
'channels': [0,3],
'pixels': [0,2,5,7,9],
'colors': ['FF0000','00FF00','0000FF']
}
When providing multiple colours, as each pixel is rendered in a channel, the pixel will take the colour at the pixels index in the colour list. If the colour list is shorter than the number of pixels, then the colours will be looped through mulitple times. So in the example above, the selected channels will have pixel colours:
red, green, blue, red, green, blue, red...