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Re: Micro UK101 Build
Posted: Fri Oct 11, 2013 3:55 am
by clockpulse
Certain factors make this trick undesirable. Yes, it saves a byte or two (compared with an actual BRA or JMP). But -- besides any human confusion it may cause! -- there will also be an access to location $07A9, and that can disrupt operation of certain I/O chips should they happen to be mapped there.
I have ran into things like this before, I think on some occasions the programmer may have used this trick to fool a disassembler and keep their code a little more secure but without thinking about possible problems that you mention.
Re: Micro UK101 Build
Posted: Sun Oct 13, 2013 6:04 pm
by Simon
Cool, thanks for the explanation. That's used a few times in the MS Basic code. Unfortunately I didn't get any time to play with it in the weekend. My PC melted down on Saturday so I ended up building a new one. Still trying to get the on board parallel port working so I can use my ROM programmer.
Simon