Re: A85: FA70-FBFF?
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Re: A85: FA70-FBFF?
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-> assembly-85-outgoing; Thu, 21 Aug 1997 00:39:08 +0200
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-> Date: Thu, 21 Aug 1997 00:31:01 -0700
-> From: Jimmy Mårdell <mja@algonet.se>
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-> Subject: Re: A85: FA70-FBFF?
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-> Richardlewis wrote:
-> >
-> > What is in memory at FA70-FBFF?
-> > Is it just zeros, or is it actual data?
-> > TI-RAM11.TXT has no information on it. If it is just zeros, it
-> could be > used for an interrupt table (ROCK ON!!). Then we wouldn't
-> have to use a table > internal to the shell, or the graph mem.
-> It's the stack, which usually only uses 20-30 byte (starting at $FBFF
-> going down).
-> You could most likely use $FA70-$FB80 without worrying about colliding
-> with the
-> stack. You can't put an interrupt table there, since it would need to
-> start
-> at $FB00 and end at $FC00, ie one byte too much :(
Couldn't you move the stack, then change the stack pointer?
I even got an idea on how to load SP in to HL (there is no direct Z80
command to do that).
Here is the source to ld HL,SP:
ld HL,$0000 ;HL = 0
add HL,SP ;HL = SP (0+SP)
easy enough!
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