Low-power example for Longan CANBed 2040

This an a sample project for low-power interrupt-driven operation on the Longan CANBed 2040, ideal if you need to run from a battery. It uses the Pico SDK.

To minimise power consumption, it uses:

• The low-power sleep functionality of the RP2040 chip, similar to the hello_sleep example in pico-examples.
• The low-power mode of the MCP2515 CAN controller.
• The low-power mode of the SN65HVD230 CAN transceiver.

To be able to use the low-power mode of the SN65HVD230, you need to wire the RS pin to a GPIO. I did it so:

To run

./install.sh
cd build
cmake ..
./gregmake.sh