DISCLAIMER:
I will not be held responsible for any damage caused by the use/misuse of
this software. Use it at your own risk. Do not distribute it with ROMs.
Do not ask me for ROMs, or where to find them. I am sure you know how to
use a search engine.

All code written by me D.Devenport (DDevenp666@@aol.com).
Except TWKUSER.C which is public domain written by Robert Schmidt
of Ztiff Zox Softwear, 1992-93.

The archive should contain the following (and only the following files):
    DOS4GW.EXE
    README.TXT
    BBC.EXE

This program is an alpha release of an attempt to emulate the total hardware
of a BBC Model B by Acorn Computers. This program is public domain as long as
it is distrubed for FREE. If you use it send me a email, and tell me what
you think.


Requirements:
First you need two files (Don't ask me for them)
OS.ROM    - this is an image of the OS 1.2 ROM
BASIC.ROM - this is an image of the BASIC2 ROM

This program is compiled for a 386 processor. A Pentium is highly recommended
at this stage of development. Every time I try and optimise the 6502 code I
manage to break it. Therefore it is staying as is for a while, while I get
the graphics modes sorted. Then and only then will a major effort be put into
optimising the code.


Hardware currently supported and emulated (I hope correctly):

    6502 processor - BCD may be dodgy (can anyone test this?)
    6522 VIA's System and User
    ROM Paging
    ADC Controller - although I haven't yet bothered transferring information
                     from the PC joystick to the ADC registers.
    Sound - all registers, although I have yet to pass this on to the sound
            blaster
    6845 CTRC + Video ULA - at the moment only the TELETEXT chip generates
                            any output onto the VGA display. Other modes
                            just display internal information. 'Mode 8' is
                            emulated.
    Keyboard - see below for keyboard mappings


Known problems:
No filing system :(
   - you can '*LOAD' into memory using F11 though :)
Aspect ratio not quite correct on MODE 7 (or other modes for that matter but
they aren't included in this release). If you manage to get a better aspected
240x256 x 256 colours mode let me know!
(Also my 640x256 x 16 colours mode doesn't yet fill the screen vertically -
again let me know).
Keyboard - keys need to be held for sometime on a slow machine to get a
response (Pentium users won't notice this).


Keyboard mappings (different from PC)
Beeb    PC

BREAK   f12
f0-f9   f1-f10 (f0 is f10)
up      up
down    down 
left    left
right   right
- =     - 
^ ~     = 
3 #     3 
6 &     6
7 '     7
8 (     8
9 )     9
0       0
DEL     BACKSPACE
COPY    KEYPAD 0
; +     ;
: *     ' (right quote)
@       ` (left quote)
 _     #
SLOCK   NUM LOCK



Have fun!

Cheers
Dave.
