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Would you like signs with those chars?

Would you like signs with those chars?

Posted Oct 25, 2022 12:54 UTC (Tue) by dskoll (subscriber, #1630)
Parent article: Would you like signs with those chars?

Mostly OT... I first learned assembler on the Motorola 6809. It had two sets of conditional branch instructions: One set interpreted the comparisons as signed, and the other as unsigned. It's been decades since I did any Intel assembler, but I assume the same thing holds? Are there any real architectural reasons to prefer signed over unsigned or vice-versa?

The 6809 had an instruction called SEX. It sign-extended accumulator B into double-accumulator D. It also had a BRA instruction, which was an unconditional branch. Someone tended sophomoric when naming the instructions. :)


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