pi_clock

Show the time and weather using a Raspberry Pi and an LCD display

Usage:

Build and run locally

cargo run -- --uri='http://some-cache.local'

Build and deploy to remote sever

There is a deploy script provided to facilitate cross-compilation and deployment.

It requires cross to be installed

./deploy --target 10.0.1.10 --release

Raspberry Pi config

Some useful configuration for Raspberry Pis:

Setting up SSH and Wifi

The official Raspberry Pi Imager tool supports initial config like hostname, wifi config, enabling SSH, etc.

The 64-bit lite OS is a good option: modern hardware (e.g. Pi 3, Pi 4, Pi Zero 2) supports 64-bit instructions and there is no need to install the full desktop OS.

The Pi Zero W only supports 2.4GHz; the Pi 4B also supports 5GHz.

Enabling Pulse-width Modulation (PWM)

PWM is used for the brightness of the LCD and TFT displays.

• Add the line dtoverlay=pwm-2chan to the file /boot/config.txt and reboot.

Enabling I2C

I2C is used to connect to the VEML7700 light sensor.

• Enable it via the raspi-config utility.

Enabling programs to run on startup

• Add the command (with a trailing & to /etc/rc.local) and restart.

GPIO permissions

On the first run, we often see GPIO permissions issues. Subsequent executions seem to be fine.