Custom Arduino with ATmega2560

Projects General Guidance
4

GoForSmoke:
Cross Roads Electronics

See if the mini-2560 has 3.3V option. If not, Bob would probably sell you one set up for 3.3V.

If you only need an extra serial port, more pins and RAM, look into the ATmega1284P, it's got 16K RAM.

I need four UART channels.