Changes

X-MEM

863 bytes added, 09:42, 14 January 2018
CPC X-MEM
 
== Technical ==
 
ROMs are selected using the normal ROM selection I/O port (DFxx).
 
The CPC sees Roms the X-MEM at rom slots 0-15 and &40-&4f.
 
&40-&4f are always visible regardless of the ROM lock or ROM boot switches. If you wish to program the flash use the &40-&4f range.
 
When "boot from CPC" is activated, rom 0 and OS are not paged in by the X-MEM but can still be accessed at &40 etc.
 
The flash is mapped contiguously to roms 0-15 so that when programming the flash you need to translate the flash address from the documentation to an appropriate rom slot and address in the range &c000-&ffff.
 
e.g. for flash address &05555 use DF41 and address &D555. For &2aaa this is DF40 and address &EAAA.
 
TO BE CONFIRMED: Writing to the flash also writes to the RAM underneath the ROM?
TO BE CONFIRMED: Writing to the flash requires upper ROM to be paged in?
 
 
== X-MEM Floppy Disc Utilities ==
=== X-MEM Init Pass ===
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