I am trying to do a mechanical efficiency project with my students, but we need to be able to hook a V5 motor to a breadboard. I cut a cable and it has 4 wires (red, black, yellow, green). I assume red and black are power and green and yellow are encoder, but not positive about that. When I hook red and black to power I get nothing. I assume it has something to do with the internal encoder, but not sure how to satisfy it or override it. Has anyone done this successfully?
Not an expert on vex by any means, so take what I say with a grain of salt.
It looks like the VEX motors use the “RS485” protocol.
So you are at least partially correct - the red/black are power. The green/yellow are serial data links for said protocol.
You cannot just apply a voltage and expect the motor to do something, as it needs some form of instruction along those two data lines. It may be possible to splice in a control signal from a vex brain(?), but I’m unsure about this
I don’t have an answer for you, but you might be better off asking on https://vexforum.com since iirc there are technical peeps from VEX, as well as people who may have done a similar project there.