Hi!
I'm thinking of turning this project into a PCB:
Building a USB UART Serial Adapter
As part of that, I thought a few bits of functionality could be added at low cost:
(a) an MSP430 programmer
(b) perhaps a voltage monitoring capability since there is an ADC on the MCP2221
However, I wanted it to be a super-simple project. The current project uses jumpers to select 5V or 3.3V logic level UARTs. One solution could be
a switch, but it would be nice to not have a switch either.
To eliminate that, I'm thinking of making the Rx pin 5V tolerant, but leave the Tx pin at 3.3V logic levels. This should therefore be compatible with any boards
that use 3.3V levels, but also the 5V Arduino Uno (it should be fine with 3.3V logic level input according to the ATmega datasheet).
(I'll also make it somewhat tolerant to accidentally swapping round of Rx and Tx).
My question is, does anyone know, are there any popular 5V boards that would not be OK with 3.3V logic level?
(I know now there are 1.8V boards too, like the Odroids, but that is a complication too far, so this board will only handle 3.3V and have the tolerance for 5V).
Thanks!
