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Message: 4415

Author: john_elliott_uk

Date: 23/08/2004

Subject: Re: Comments from Geoff Eddy re. Patch Vectors

 

In manicminerandjetsetwilly@yahoogroups.com, Alexandra wrote:

I was using a TAP. If I used seperated files I'd get confused as to
what *actual* spectrum address I was editing. Though I guess there's probably an easy way of working out where the address of room N's
patch is.

If you want to put code in a room definition, then (with +3DOS
files) you use this formula:

rooms.js1: Rooms 0 to 31 (V,W); 0 to 15 (others)
rooms.js3: Rooms 32 to 63 (V,w); 16 to 31 (others)
rooms.js4: Rooms 64 to 95 (V,W); 32 to 47 (others)
rooms.js6: Rooms 96 to 127 (V,W); 48 to 63 (others)

In a V/W game, the rooms are than at 80h, 280h, 480h, 680h...
while in the others, the rooms are at 80h, 480h, 880h, 0C80h...

The current room will always be at Spectrum address 8000h, whatever
the game format. So in a V-format game, your patch vector code will
(probably) start at 8100h.

 

 

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