A Cortex programming question for the oldheads

Tell me what I’m missing here. This is the exact same code I’ve used for years to tankdrive a squarebot chassis

#pragma config(Motor,  port2,           leftDrive,     tmotorVex393_MC29, openLoop)
#pragma config(Motor,  port3,           rightDrive,    tmotorVex393_MC29, openLoop, reversed)
//*!!Code automatically generated by 'ROBOTC' configuration wizard               !!*//

task main()
motor[port2] = vexRT[Ch3];
motor[port3] = vexRT[Ch2];

What it should do is left joystick controls left drive, right joystick controls right drive. What it does do is run both motors for 4 seconds and stops.

I don’t see anything wrong with the code, perhaps code is not being downloaded to the cortex properly for some reason.


I’ve written other programs (run motor for 1 second, stop) and they work fine. I’ve updated CPU and Cortex firmwares on the cortex, updated joystick firmware on the controller, used multiple joysticks, cortexes, and programming cables.
I’ve checked that I don’t have any other programs in background tabs.
I’ve set it to VEX Cortex 2.0 and to Natural Language PLTW.

I’m out of ideas as to why a historically simple, rock solid program is acting this way.

I’ve seen this before where the download is something old. Dig in the cortex code directory for the .hex file and delete it. That will force the compile to happen.

The only .hex file I could find there, VEX_Cortex_1056.hex, gives me the error message “FILE ACCESS DENIED You need permission from SYSTEM to make changes to this file”

yea, don’t delete that one, it’s the RobotC firmware.


I found a laptop with RobotC and was able to program using it. I guess my teacher desktop is just borked. Thanks to those who tried to help.

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