>>I was needing an (very) efficient way to rotate a byte a variable number
>> of positions when the following popped on my mind:
>>
>>
>>        btfsc    TABLAT, 2, ACCESS
>>        swapf    PRODL, F, ACCESS
>>        btfsc    TABLAT, 1, ACCESS
>>        rrncf    PRODL, F, ACCESS
>>        btfsc    TABLAT, 1, ACCESS
>>        rrncf    PRODL, F, ACCESS
>>        btfsc    TABLAT, 0, ACCESS
>>        rrncf    PRODL, F, ACCESS
>>
>>
>> The number of positions to rotate is in TABLAT and the value to be
>> rotated is in PRODL.
>> The routine can rotate from zero to 7 positions, takes only 8
>> instructions and as a bonus it is isochronous.

Actually, this algorithm properly handles rotate counts from 0 through 255!

-- Bob Ammerman=20
RAm Systems

--=20
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