Some Examples

All hex numbers represent signed decimal in two’s complement format.

$ FF = -1

+ $ 01 = + 1-------- $ 00 = 0

Note there is a carry out, but the answer is correct. Can’t have 2’s complement overflow when adding positive and negative number.

$ FF = -1

+ $ 80 = -128-------- $ 7F = +127 (incorrect!!)

Added two negative numbers, got a positive number. Twos Complement overflow.

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