Hi, I've got a device I'd like to interface with which uses 2.8V serial signaling. What's the simplest route I can take to translate between arduino's 5V signaling and the 2.8V I need? I intend to use the 'soft serial' example I've seen on the arduino site for communication.
An excellent explanation (although no simple solution)
I've successfully used a transciever to do this. It allows you to communicate between 2 data buses, where each can run at a different voltage. I needed to do something similar to what you are trying to do, except in my case it was Arduino to XBee, where the latter expects 3.3v. I used an SN74LS245 chip to drive the 3.3v Rx input on the XBee from the Arduino 5v Tx pin. Going the other way, i.e. XBee to Arduino, I simply pass the 3.3v from the XBee directly into the Arduino, the 3.3v being sufficient to register as HIGH in the Arduino. I should also mention that this approach also requires a power supply at the required voltage, in your case 2.8v. This shouldn't be too much of a problem so long as you can find a voltage regulator that takes 5v input and outputs the 2.8v.