CM4-WRT-A: Raspberry Pi CM4 Gigabit Router Baseboard with NVME Support
The CM4-WRT-A is a Raspberry Pi CM4 carrier board that can be used to create a gigabit router capable of supporting WiFi 6/6E as well as a 4G/5G backup connection.
How to install OpenWrt on a CM4-WRT-A router
The first step is to generate a firmware image with all the necessary drivers to access the second Ethernet port (ETH1), NVME storage devices, as well as the i2c bus on the CM4-WRT-A router board.
How to monitor the CM4-WRT-A board temperatures and fan speed (RPM) in InfluxDB
The CM4-WRT-A OpenWrt image includes a service called picod, which communicates with the Raspberry Pi Pico collecting periodic measurements from six temperature sensors on the CM4-WRT-A board, as well as the system fan Revolutions Per Minute (RPM).
How to interact with the OpenWrt service picod on the command line via ubus
The CM4-WRT-A software includes a service called picod, which naively supports ubus (micro bus). The OpenWrt micro bus architecture provides inter-process communication between various daemons and applications in the OpenWrt project.