I run the QEP modules in the PWMSS subsystems. All works well, unless I try 
to switch the Quadrature Count mode (QDECCTL:QSRC bits). My target is to 
change the mode dynamically (while the module is running). This works well 
when I switch from Quadrature-count mode to Up-count mode.

But when I switch the other way from Up-count mode to Quadrature-count 
mode, the Edge Caption Unit doesn't generate UPEVNT signals at low speed 
for a certain time. Then, after some time (or at high speed), it starts to 
work as expected. The down-time at low speed varies between 5 and about 500 
Unit timeout events (at random).

The TRM says 

The QCAPCTL register should not be modified dynamically (such as switching 
> CAPCLK
> prescaling mode from QCLK/4 to QCLK/8). The capture unit must be disabled 
> before
> changing the prescaler.
>

I don't change the prescaler (CCPS bits), just the binary divider (UPPS 
bits). But even if I disable the Edge Caption Unit before changing its 
configuration and re-enabling it, it doesn't work immediately.

Did anybody see this issue yet? Or solved it? If so, how?

Thanks in advance!

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