Re: A86: Re: Ram Screen program.
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Re: A86: Re: Ram Screen program.
Jeremy Goetsch wrote:
> >Don't ask me why hl points so
> >high when _puts is used, I have no clue. Could someone please explain?
> >
>
> Your sqrtKEY handler program is essentially a program within a program. When
> a key is pressed, the part between "code" and "code_end" will be copied to
> _asm_exec_ram and executed. Hence, the label "code", when executed, will be
> equivelent to _asm_exec_ram. In the installer program, however, this is
> obviously not the case, as there is all that installer code before it. The
> assembler doesn't know that this will be run as a separate program, so it
> calculates the labels, including "memmenu", in relation to the beginning of
> the entire installer program. So what you have to do is subtract the
> difference between the start of the handler code ("code") and the start of
> the installer code (_asm_exec_ram) every time you give an address in the
> handler code (except for relative addresses).
>
> What I like to do is define a macro for this, like:
> #define CodeOffset (code - _asm_exec_ram + 2)
>
> (The +2 is because the 8E28 token will not be copied or executed.)
>
> Then just use:
> ld hl, memmenu - CodeOffset
> instead of:
> ld hl, memmenu
>
> Later,
> Jeremy G.
An easier way to use a second .org, so that the labels are organized under
_asm_exec_ram starting at where the code begins. It can be tricky to get the
copy labels correct, but if you use this for a template, you shouldn't have a
problem: http://www.eden.rutgers.edu/~assets/KeyTemp.asm
Note: TASM will wack out, so only do this if you're using Assembly Studio
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