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+---- Thread: What is the reserved data at $FF18 - $FFFF? (/showthread.php?tid=883)
What is the reserved data at $FF18 - $FFFF? - JMcGibbitts - 06-16-2019
Hi.
I see data from address $FF18 (65304) - $FFFF. 231 bytes. It seems to start with F3 0D CE 0B E3 50 CE 0B... I have not seen it change size or start address across a few programs.
What is this data? Does it remain constant / static?
Provided I keep my main program code < $C000 and I copy this reserved data from $FF18, into all 128K banks 1-7, will I be free to use 128K paging as I choose, loading data and / or binary code into each page at specific addresses?
Will the program need this reserved data in the other 128K pages or is it maybe only used during program initialisation?
Thanks!
Re: What is the reserved data at $FF18 - $FFFF? - boriel - 06-16-2019
That's mostly old RAMTOP data plus UDG old data (unused). So it's not reserved. If you use --sinclair for compatibility, then yes, UDG will be used in another memory region.