assembly - When are the carry flags set? -

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what meant "applying neg instruction nonzero operand sets carry flag."

 why substracting 2 1 set carry flag?             00000001 (1)  +         11111110 (-2) [in 2-complement form]  --------------------- cf:1       11111111 (-1) [ why carry flag set here???]

you view neg a equivalent sub 0, a. if a non-zero, set carry flag (as always result in unsigned overflow).


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