AQPy
Repository for scripts and files to read the PMS5003 air quality index sensor and the BME280 temperature/pressure/humidity sensor from a Raspberry Pi. systemctl
is used to manage the read_sensors.py
python script. The data is stored into a postgresql database with the timescaledb extension. From there, Grafana is used to plot the data over time.
Hardware
PMS5003
The PMS5003 is assumed to be connected over serial in the /dev/serial0
position. See the PMS5003 manual for wiring diagram of the PMS5003. The pinout
command on the Raspberry Pi OS will show the function of the GPIO pins.
PMS Wire No. | Raspberry Pi Pin No. |
---|---|
VCC (1) | 2 |
GND (2) | 6 |
SET (3) | unused |
RX (4) | 8 |
TX (5) | 10 |
RESET (6) | unused |
BME280
The BME280 is assumed to be connected with I2C.
BME280 Terminal | Raspberry Pi Pin No. |
---|---|
3V3 | 1 |
GND | 9 |
SCL | 5 |
SDA | 3 |
Installation
- copy
aqi.service
to/etc/systemd/system
withsudo cp aqi.service /etc/systemd/system
- run
sudo systemctl enable aqi
to startaqi.service
at boot - either
sudo reboot
orsudo systemctl start aqi
to start the service - make sure its running with
systemctl status aqi
. It will say "active (running)" if things are working properly.
Maintenance
systemctl
stores logs that can be accessed through journalctl -u aqi
. journalctl
uses the less
linux utility to show the logs. A brief summary of aqi.service
can be obtained by running systemctl status aqi
. If the sensors stop working (or I didn't code things robustly enough) the python runtime errors will be recorded by systemctl
. If the read_sensors.py
script fails, systemctl
will automatically restart it however if it fails too many times it will wait longer and longer between retries.