2 Replies Latest reply on Jan 24, 2014 5:15 AM by RaAl_264636

    Datapath shift operation: what happens on a left/right shift if the shift output is set to right/left?






      I'm digging deeper into the datapath shift operation. I wonder what happens if a left/right shift operation is executed with the shift input or output set to right/left? Unfortunately I couldn't find explicit information about this special cases in the architecture technical reference manual.




      For example, a typical configuration would be Shift = right, Shift in = from left (SIL), Shift out = right (SOR)


      Now, if Shift out = left (SOL_MSB), the shift output will simply follow the shift input, right?




      What happens if Shift out = right (SOR) and Shift in = from right (SIR)? If I understand the shift mechanism right, this combination is not possible, because the shift direction automatically selects the corresponding shift input. Is this true?