Faster SHIFTOUT without dedicated hardware, possible?

[CuriousOne]

I also tried to add some NOPs as suggested above - no difference.

[tumbleweed]

Don't know what to tell you... the routine transfers any values for WREG so there's no difference between odd/even values.

Must be some issue with the APA102C timing/format.

[CuriousOne]

I will hook up scope and check both "versions", to find the possible issue.