After a few years of trouble-free operation, my TX stopped working:
1- It does not do the auto-calibration (left/right limits) on power-up. On power-up, the Mode light on the lower left first turns red briefly, then green briefly, then blinks red (about 3 per sec.).
2- The wheel is locked up and vibrates, as though the FFB motor is fighting itself. There are very small left/right movements of the wheel occasionally.
After lots of digging around, including motor disassembly to check the rotor (it was fine), I found that one of the 3 mosfet pairs was not getting a signal to its gate. I traced this back to the microcontroller's PWM output pins and sure enough, one of the 3 pairs is not putting out a signal. One output is stuck high and one stuck low. The other 2 PWM pin pairs look like normal output.
I assume this is why the motor is stuck in a vibrating mode, since it can't rotate with one of its poles not getting energized. The question is whether the microcontroller is bad or maybe its not getting position information from the motor?? I do see a pulse waveform coming from the rotary encoder PCB on the end of the motor shaft. The pulses change when the shaft is rotated but I can't interpret whether its correct.
Also, does anyone know if the cylindrical magnet on the motor shaft has to be oriented in some way relative to the shaft? I would think the start-up calibration would handle this. But when checking out the motor, I found the magnet was just friction fit to the shaft -- pretty firmly and I doubt it would rotate -- but I could (and did) move it. There are no visible alignment marks on it. There's about a 1mm / 1/16" gap between the magnet and bottom of the encoder PCB. I don't think its an encoder problem, but it seems odd that one PWM channel of the microcontroller would suddenly fail.
Note- PC driver and TX firmware both install without errors and are up-to-date, but wheel is not seen by TX Control Panel. As soon as the firmware upload completes, the wheel tries to do an auto-calibrate and immediately locks up.
Any clues?
1- It does not do the auto-calibration (left/right limits) on power-up. On power-up, the Mode light on the lower left first turns red briefly, then green briefly, then blinks red (about 3 per sec.).
2- The wheel is locked up and vibrates, as though the FFB motor is fighting itself. There are very small left/right movements of the wheel occasionally.
After lots of digging around, including motor disassembly to check the rotor (it was fine), I found that one of the 3 mosfet pairs was not getting a signal to its gate. I traced this back to the microcontroller's PWM output pins and sure enough, one of the 3 pairs is not putting out a signal. One output is stuck high and one stuck low. The other 2 PWM pin pairs look like normal output.
I assume this is why the motor is stuck in a vibrating mode, since it can't rotate with one of its poles not getting energized. The question is whether the microcontroller is bad or maybe its not getting position information from the motor?? I do see a pulse waveform coming from the rotary encoder PCB on the end of the motor shaft. The pulses change when the shaft is rotated but I can't interpret whether its correct.
Also, does anyone know if the cylindrical magnet on the motor shaft has to be oriented in some way relative to the shaft? I would think the start-up calibration would handle this. But when checking out the motor, I found the magnet was just friction fit to the shaft -- pretty firmly and I doubt it would rotate -- but I could (and did) move it. There are no visible alignment marks on it. There's about a 1mm / 1/16" gap between the magnet and bottom of the encoder PCB. I don't think its an encoder problem, but it seems odd that one PWM channel of the microcontroller would suddenly fail.
Note- PC driver and TX firmware both install without errors and are up-to-date, but wheel is not seen by TX Control Panel. As soon as the firmware upload completes, the wheel tries to do an auto-calibrate and immediately locks up.
Any clues?
