strange assembly problem

CJ

for some reason, I get garbage data in my Gamecube controller driver when trying to optimize some of my code

I clear the data holding registers at the beginning of my loop to 0
then as the data comes in I use the carry flag to set the data bits accordingly

I am trying to replace this

IF_C OR data1, #1
        SHL data1, #1

with this

RCL data1, #1

are these not equivalent, or am I missing something here?

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Mike Green

They're not equivalent. The first one effectively copies the C flag into the LSB of data1, then shifts it left. The second one shifts data1 left, then copies the C flag into the LSB (sort of).

CJ

thanks, looks like I have some LSB bugs to tackle in my recently posted objects, fortunately they stem from one source

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