For a robot project I am using an Arduino Uno, and am running out of pins. The simplest solution would be to use digital pins 0/1. I know this means that I won't be able to use Serial communication (which is fine), but I also know that these pins are also used when uploading code to the board, and connecting components to these pins can interfere with the upload.
Are there certain types of components/interfaces that can be connected to these pins that won't interfere with the upload (without having to disconnect them every time I want to upload)?
In my case, I can choose between either using these pins to drive inputs for an L298N motor driver (TTL inputs), or to read quadrature motor encoder signals. My guess would be that the latter won't work, as these signals may be high and interfere (and I don't know whether applying a voltage to the encoder outputs would cause damage - I have no datasheets for them).
However maybe the TTL inputs of the L298N would be fine? Or do I have no choice but to either have a switch to disconnect the when uploading or find some other way to reduce pin usage (or go for a bigger Arduino)?