TReX TTL at 3.3V

Are the TReX and TReX Jr. friendly with controllers using TTL 3.3V?

It has been working fairly well but I’ve encountered a few issues that I can’t seem to resolve while using a 3.3V chip to communicate with a single TReX. Figured I would ask this question before I assume one way or the other :slight_smile:

Hello.

The TReX and TReX should be able to handle 3.3V signals. The serial input line on the TReX is guaranteed to interpret any voltage above 0.6*Vcc (~3V) as high. 3.3V is close to this limit, so your tolerance for noise will be much lower. Do you have an oscilloscope you can use to see if there’s any noise on your serial line? Please note that the TReX transmit line will be transmitting at 5V, so please ensure that your 3.3V side is 5V tolerant, or use intermediary electronics (e.g. a voltage divider) to protect it.

- Ben