I replaced the thumbsticks on my 1697 model with new hall effect based thumbsticks. Is it possible to calibrate the thumb sticks? The controller firmware seems to have internal stored calibration values of old ALPS potentiometer thumbsticks. Unfortunately the new ones are slightly off center and have different full-scale deflection ratio. At about 50% stick deflection the controller reports 100% value. I accuse the stored calibration, because I measured the full-scale deflection linearity of hall effect sensor in circuit. Output voltage range of hall effect sensor "wiper pin" is about 0.2V - 1.7V but interpreted range of ADC input seems to be somewhere from 0.5V - 1.4V.
I guess the controller still has its original firmware and I cannot upgrade firmware or use XBOX Accessories App (also the downgrade launch option doesn't help). Tried on multiple PCs with USB or wireless.
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I also tried newer XBOX controllers, but I do not want to use them as they still do not use hall effect sensors and even worse, the firmware uses an integrated averaging filter for the thumbstick to "heal" drift issues, so that users won't notice the drift. However this filter leads to quadratic and non-concentric stick movement.
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I also tried newer XBOX controllers, but I do not want to use them as they still do not use hall effect sensors and even worse, the firmware uses an integrated averaging filter for the thumbstick to "heal" drift issues, so that users won't notice the drift. However this filter leads to a square gating and not a circular gating stick movement.
Currently I can see only 2 options:
* use an intermediate op-amp mod to adjust the "wiper" range to the old values
* try to reverse engineer the firmware running on the MKL26Z256VMC4 chip and find and update stored calibration values
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I will try the latter one as I'm more into software.
I replaced the thumbsticks on my 1697 model with new hall effect based thumbsticks. Is it possible to calibrate the thumb sticks? The controller firmware seems to have internal stored calibration values of old ALPS potentiometer thumbsticks. Unfortunately the new ones are slightly off center and have different full-scale deflection ratio. At about 50% stick deflection the controller reports 100% value. I accuse the stored calibration, because I measured the full-scale deflection linearity of hall effect sensor in circuit. Output voltage range of hall effect sensor "wiper pin" is about 0.2V - 1.7V but interpreted range of ADC input seems to be somewhere from 0.5V - 1.4V.
I guess the controller still has its original firmware and I cannot upgrade firmware or use XBOX Accessories App (also the downgrade launch option doesn't help). Tried on multiple PCs with USB or wireless.
I also tried newer XBOX controllers, but I do not want to use them as they still do not use hall effect sensors and even worse, the firmware uses an integrated averaging filter for the thumbstick to "heal" drift issues, so that users won't notice the drift. However this filter leads to quadratic and non-concentric stick movement.
Currently I can see only 2 options:
* use an intermediate op-amp mod to adjust the "wiper" range to the old values
* try to reverse engineer the firmware running on the MKL26Z256VMC4 chip and find and update stored calibration values
I will try the latter one as I'm more into software.