Another component you'll need for a straightforward LED sign build is a Pi HAT. A Pi HAT is a term used to describe additional hardware attached to the top of a Raspberry Pi unit.

Vcc Labs has created a Raspberry Pi RP2040-powered RGB LED matrix that's super small and powered via USB Type-C.

The LED display in question is of the 64×64 RGB type, available from Aliexpress and other electronics suppliers online. To run the display, an Adafruit RGB Matrix Hat is used with the Raspberry ...

Second, it has a 4-pin I2C connector instead of a 3-pin debug connector. And third, the BPI-Pico-RP2040 has an RGB LED light. Otherwise, the two boards are nearly identical.