I want to interface two MCU's, one is at 3.3V and the other at 5V. The problem is that the 3.3V device is sensitive, and can't handle 5V signals, so I need to step the RX line on the 3.3V device down from 5V to 3.3V. Is it possible to use a voltage divider on a serial line, or another simple way of accomplishing this without using a level converter IC?
UPDATE I haven't tried using a divider yet. I have implemented a TTL converter from Adafruit, and it works, at 9600 baud, but not at higher speeds. I have a certain amount of noise in my system, which I have a hard time getting rid of, and suspect this is the reason. I suspect a divider will be worse in this case.