TMS320F28235: QCTMR writable only if eQEP edge Capture is not activated

Hi Karim,

You're meaning the QPOSCNT register, I assume. See the description below about when QPOSCNT is read-only and guidance on when it is OK to write to the register:

Best,

Kevin

No, Karim means the QCTMR register

My experience is: QCTMR is writable if the CCPS bits are > 0, i.e. when the CAPCLK is lower than SYSCLKOUT, irrespective if CEN is 0 or 1. AT CCPS = 0 then QCTMR is not writable. 

Hi Uwe,

OK I see, thanks for explaining.

I'm not certain why it can't be written to when CCPS = 0, but it could be because QCTMR is constantly counting up on every SYSCLK cycle when CCPS = 0 (i.e. CAPCLK = SYSCLK / 1). This would be similar and match up to the note for the QPOSCNT register 'This Register acts as a Read ONLY register while counter is counting up/down'.

Curiously, why are you wanting to write to the QCTMR register while actively counting?

Best,

Kevin