Motorola 24-Bit Digital Signal Processor, DSP56000 manual Condition Code Computation

CONDITION CODE COMPUTATION

C (Carry Bit)	Set if a carry is generated out of the MS bit of the A or B result of
	an addition or if a borrow is generated out of the MS bit of the A
	or B result of a subtraction. The carry or borrow is generated out
	of bit 55 of the A or B result. Cleared otherwise.

Table A-5shows how each condition code bit is affected by each instruction. Exceptions

to the standard definitions given above are indicated by a number or a “?”. Consult the

corresponding note for the special definition that applies in each particular case.

Although many of the instructions allow optional parallel moves, Table A-5 applies when there are no parallel moves associated with an instruction. With this restriction, the states of the condition code bits are determined only by the execution of the instruction itself. However, the S and L bits may be determined differently than shown in the table

when a parallel move is associated with the instruction. When using an optional parallel move, refer to the individual instruction’s detailed description in Section A.7 to see how the S and L bits are determined.

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