IME Issues

I’ve read in multiple places on the forums that the IME’s are not the best choice for sensors to use on your robot for distance control. But I’ve been trying to work with them all year and for the most part they have been great. My team uses easyC for the programming software and the problems that we are having now is that in the on-line window it shows that the encoders are reading values and all that. But once the smart tasks come into play it doesn’t seem to use the values. For example, say we had it set to drive at 50 motor value for 180 degrees, it uses the motor value but the motors never stop turning. After a lot of trouble shooting we got the IME to work that is on the drive motor. But the one on the lift continues to give us problems. I’m wondering if anyone else has had similar issues and how they fixed it. We’ve tried different 4 wire cables, different encoders, different order of encoders in the daisy chain and I can’t seem to find a solution. Thanks for any help in advance.

@skoched967 It sounds like a coding problem. If you include the code then I might be able to help, but other than that I’m not sure.

If your IMEs were working fine before, and are not working now, it sounds like you have a problem with the devices themselves or the cables connecting them. Do all of the lights on your IMEs blink green the way they’re supposed to? When not in use they should do a green double-blink, then off for a few seconds, then repeat. When the motor is running, the green light should flash constantly in proportion to how fast the motor is turning – slow motor, slow, evenly flashing green light; fast motor, fast evenly flashing green light.

The first comment in this thread, from @jpearman has a good troubleshooting process to help confirm that each IME and each cable is functioning properly. Unless you know for sure, starting from the cable leading out of the cortex, that every cable and every IME is functional, you can’t eliminate a physical defect as a source of your problems.

Do you have an LCD screen? It will help tremendously to do your troubleshooting to have values written to the screen as your robot is performing its functions instead of having to be connected to the on-line window; with the online window, as you can tell, you only know what’s happening in a testing environment, you don’t know what’s actually happening when the robot is running your code. With an LCD screen, you can have 2 encoder values printed to the 2 lines of the screen continuously (or at selected points of your program), so you can see if the robot is even reading the values during the program. (We also use easyC.)

Hope this helps.