SDX High Memory

About the BASIC system (not including PROGRAMMING)
Bill B
Posts: 243
Joined: 26 Jan 2014 16:31

Re: SDX High Memory

Post by Bill B » 28 Mar 2020 19:43

Should anybody be interested, attached is my disassembly of the SDX high memory.

There are two major areas of unused memory at:
  • EC5F - F5B0
  • F5EF - FA52
Much of this space is used by data structures for the NODE RING if that is installed.

Adopting the principle of overwriting unused parts of the BDOS and BIOS, the following space could also potentially be used:
  • D812 - D840 - Part of Read Console Buffer
  • D912 - ???? - Depends how low the BDOS stack gets - More of Read Console Buffer
  • E5C3 - E67D - BIOS Cold Boot code
  • E700 - E7E0 - Keyboard, Display and Serial I/O
Attachments
sdxmem.zip
(40.45 KiB) Downloaded 37 times

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