Re: 6502 flag behaviour

[dalloff@freenet.columbus.oh.us (Dave Althoff)]

David Schmidt (anonymous@fight.spam) wrote:

: This is actually pretty common in 6502 assembly--I did it all the time.  If you
: need to jump to somewhere within +/- 127 bytes, look above and find some
: condition that is always true, and branch on it.  Compared to a regular JMP,
: saves 1 byte and several machine cycles.

Not to mention that conditional branches are relocatable.  Granted, that
isn't a problem if you are writing linked modules for GS/OS, but if you
are doing classic 6502 code, fully relocatable code can be really useful. 
For example, if you want to have a code library floating above the end of
an Applesoft program, it had better be relocatable...which means no
internal ($4C) JMPs or ($20) JSRs...

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