A89: Important question


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A89: Important question




Hi!

I have very important question which I can't check by myself because
I have not a graphlink. The question is: what happens on real 68000
(e.g. on real TI-89) if you tried to jump to the address which is
greater than 16 MB (note that PC register on 68000 is 24-bit long,
so the max address is 16 MB)? My assumption is that the highest byte
will simply be ignored, e.g. the instruction like

jmp $12345678

would be interpreted as

jmp $345678

I hope that the same is true for other "indirect" jumps, especially
using "rts" (e.g. I hope that if the address on the stack is
$12345678, then "rts" will jump to $345678).

Can somebody check this? If my assumptions are true, I have an extremely
simple method to implement "exit" and "atexit" functions in "stdlib.h"
C header file (namely, I want a method for implementing these functions
which does not bloat the compiled code if these functions are not used
in the program). If my assumptions are correct, I have a solution. But
if the assumptions are not correct (e.g. if the result is "Address
Error" or something ugly like this), I am in a lot of troubles...

So, please, can anybody answer to my question?

Cheers,

Zeljko Juric




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