29 Sep
2006
29 Sep
'06
6:57 a.m.
On Fri, Sep 29, 2006 at 12:28:57AM -0400, Mathieu Bouchard wrote:
On Thu, 28 Sep 2006, Hans-Christoph Steiner wrote:
Obviously usefulness is essential.
Not even: the 6809 CPU has those two curious opcodes in it.
BRA, or branch always, means if(1) goto ...; BRN, or branch never, means if(0) goto ...;
this is among 14 other types of branches like "branch if last result overflowed" and "branch if last result was negative" and other serious stuff.
Note that 6809 already has another goto statement, called JMP.
Weird. Does the BRN have the same side effects, number of cycles etc. as a NOP? Likewise for BRA vs JMP?
Chris.
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