Hi. I recently have ran into an issue with my VEX EDR (old green robot) cortex and its functionality. I am doing a maker project for my school where I basically am going to mount the flywheel system of the nerf nemesis onto FPV drone motors and launch the yellow nerf balls out of it. Progress with that is steady, but i just ran into an issue that has stopped me dead in my tracks. Yesterday, I was finishing wiring all 4 of my drive motors to the cortex, (inputs 2-5) and it worked great, but when I plugged my ESC for the arm function (clawbot) it wouldn’t work. I put it into the 6th compartment so i could control it with the up/down buttons on the front left side of the controller, but it simply did not work. I experimented and tried again, but still nothing. Sometimes when i moved the joysticks it would raise the arm a bit, but that’s about it. Before this, I had so many different ESC’s plugged into it for the claw, one to rotate the claw, and of course, the arm, and it worked perfectly. Not sure what made it change since, but I can’t really progress with this issue, and i’m totally stumped. Could someone please tell me what the issue is, and how i can fix it? Thank you.
Are you programming your own code for it or are you using the factory default (or whatever is left) code that is installed on the Cortex?
factory default code.
I would look at the following:
1-3 ports are left drive motors
4-5, 10 ports are right drive motors
As for the other motors, yeesh.
Heres some simple code I made from a long time ago for you to program on your own. Also note that ROBOTC should have sample code you can download as well if you have ROBOTC installed:
im new to all of this. What is ROBOTC? I’ve only ever coded the newer IQ bots in my robotics class a couple years back. I know nothing about coding the EDR cortex and i have 13 days to complete this project 
ROBOTC was one of the programming environments used to program the cortex era brains, not been updated in many years, essentially obsolete at this point.
How would i go about programming it? Could you provide me with instructions to do so? Also if you could tell me how long you think it would take, I would appreciate that.
Also- I got the drone motors figured out but they have to function with a joystick. Problem being, I can’t drive the robot otherwise, unless it’s with one joystick. Is that possible?