Copyright (C) 1996 by Tom Seddon

Before you can use the emulator, you will need copies on disk of at least two ROMs: the operating system ROM from the BBC, and a paged language ROM. The most useful paged ROM to have would be BASIC (either version) since many programs assume that this is installed, but a ROM such as Wordwise Plus or ADE would do.

The operating system is mapped into memory from &C000 to &FFFF inclusive. To save a copy on disk, use the following command:

*SAVE OS C000+4000

Saving a paged ROM is more tricky. All the ROMs installed in the BBC are mapped, one at a time, into the memory between &8000 and &BFFF inclusive. Using *SAVE will cause the filing system ROM to be mapped in, and a copy of this ROM will result (not useful). The following assembler/BASIC program will save a specified paged ROM to disk.

10PRINT Please specify the paged ROM to save:
20INPUT ROM%
30FOR T%=0 TO 2 STEP 2
40P%=&900:[opt t%
50.start
60lda &F4:pha
70lda #ROM%:sta &F4:sta &FE30
80lda #&00:sta &70:sta &72
90lda #&80:sta &71
100lda #&30:sta &73
110ldx #&40:ldy #0
120.copyloop
130lda (&70),Y:sta (&72),Y
140iny
150bne copyloop
160dex
170bne copyloop
180pla:sta &F4:sta &FE30
190rts
200]NEXT
210$&700=SAVE ROM+STR$(~ROM%)+ 3000+4000
220X%=0:Y%=7:CALL &FFF7
230END

That was the easy bit. Now that you have the ROM images on the BBC end, you have to get them over to the PC.
