                                                  Excession!

Echo - previously known as oidsemu

Version 0.3beta (0.1+0.2 with a few MORE fixes !)

This program is a preview of an Atari ST emulator - therefore it's full of bugs and should only be run at your own risk!

Make sure you have a soundblaster compatible sound card, and 16bit vesa video card before running this program
A ROM-dump of the Operation System is needed and should be called
tos.img in this directory.

Press F11 to bring up a really dodgy menu (it'll be better in the next
version!)

For the interested -
This version emulates the following parts of an Atari ST/STE

(generally speaking 50% complete emulation - )

Motorola
68000 - at approx. 8 mhz  (you may need to increase this to
                             run some games)
        There are many bugs in the core, and alot of work needs to be
        done with cycle counting (for the obvious ... ;)

Shifter - All video modes, no overscan yet. Cycle accurate shifter 
          emulation is not enabled in this version (I haven't sorted               out my dodgy VAP register code ..)
IKBD - lots of things done, lots of things still to do (especially
       midi) - in mouse key mode pressing 2 buttons at the same time
       doesn't work (needed for Megalomania)

MFP - Most things emulated, I haven't looked at priorities much

Interfaces (printer, serial, midi, etc) - Not yet!

Disk (FDC) - read/writing (so be warned !) - seems to work ok (but can
             crash the emulator if a duff image is used)

Hardisk (gemdos emulation) - Very buggy, most things work but may or
         may not do strange things. Different Tos version will do 
         different things (probably).

Yamaha Sound - still need to improve emulation - a volume control
               can be found somewhere in the menus - use this mostly
               to tweak sound sample replay emulation. Samples
               and normal yamaha sound don't work concurrently - this
               will be fixed sometime!
               Check "Adaptive Sound" to improve sample sound 
               quality in a few games (Llamatron STFM, xenon,
               Captain Blood etc)
               Let me know if you want this to work in your favourite
               game (it may crash if it doesn't work!)

DMA sound (STE) - stereo sound works, but is lacking proper timer A
                  tiggering

Microwire (STE) - registers emulated (roughly), doesn't affect sound.
                  DMA&yamaha not concurrent.

Blitter - Emulated, but probably doesn't work! no attempt has been
          made for co-op/hog mode emulation

Bugs
----

When switching vesa mode, ST memory is corrupted (don't know why!)
Volume control (mostly used for my own use) only with yamaha sound.
Disk changing (the media change is not implemented when switching
               disks - so be careful)
Crashing with invalid disk images
IKBD (and/or PC keyboard routines) - these routines need improved, it's
     annoying in oids when the emulator (or oids) doesn't detect key
     releases and/or presses :(
     * Actually - I think I fixed this now (silly Ikbd timing !)
No joystick support (I don't have one !) - you're stuck with the arrow
 keys and right-ctrl !


Lots of games don't run, lots of demos don't run.
Try WinSTon or Pacifist if you can't get a game to run (but I guess
you know that already !)

            Approx size of this project !
1.9 MB (50 files) of source code of which

   130K used for CPU/BLitter code generation
   850K generated cpu code
   300K generated blitter code
   700K Emulator code

not including header files, or dos specific (Vesa, Soundblaster) code
A lot of the code is not enabled/used in this version.


Hellos to Damien Burke, and whoever is creating a Falcon Emulator ;)

Write to me (I like postcards!) -

Nick Madsen
Flat 2/2
349 Tantallon Road
Glasgow
G41 3HJ
Scotland

if you like this emulator or would like something fixed !

13/12/1998 00:45
