Hello!

What you have here is the "shar'dware version" of a graphics adaptor 
for MEGA AT computers. The archive includes the descriptions, the PCB 
layouts and some demonstration software of an adaptor to use IBM PC 
ISA graphics cards with the Tseng Labs ET4000 chipset with Atari 
computers having either a MEGA ST or an elrad ST bus system. Generally 
it's also possible to use this board with the "small" systems like the 
1040ST.

Please notice:
- This descrition is definitive not for beginners! Some explanations 
  are really short. On the other hand I will give you some more 
  detailed information you need e.g. for programming.
- This is not a direct translation of the german instructions! Since 
  there some requests I think it's better to have a short and 
  incomplete description than none. If there are enough requests I 
  will do a complete translation of the german manual.
  
There are hardly alternatives to this board for PAK/3 users now. The 
adaptor works very stable together with the HBS 640 (tested with the 
28MHz version) and with the PAK/3 (tested with up to 50MHz & Fast RAM 
(FRAK)). There are just problems in fitting all that stuff into the 
original case since Holger Zimmermann (the developer of the FRAK) 
ignored my requests in holding some place on the FRAK free since I had 
no choice in placing some parts on the board (especially the ISA 
connector). So it may be necessary to solder one GAL on the FRAK from 
the soldering side into the PCB (be very careful when bending the 
pins of the GAL!). Another solution is to use a socket for the MEGA 
bus connector. This will give you some millimetres more space so that 
the critical GAL on the FRAK may be soldered in its normal position. 
On the other hand you will still be able to close you computer's case.

Some hints for the owners of the "Crazy Dots" from TKR (which does not 
work together with the PAK/3): I've done a modification of one GAL in 
this board (which means that I have included the state machine of the 
MEGA4000 into this GAL). I have not included this GAL here for 
copyright reasons. If you are interested in this modified GAL you have 
to ask TKR. TKR is allowed to distribute and use my logic in a 
non-commercial way.

What will be needed for the graphics system?

- MEGA4000 graphics adaptor
- ET4000AX ISA graphics board (no (!) W32 boards - these don't work 
  very reliable together with NVDI so I don't support these)
- Driver software

What's included in this archive?

After extracting ET4000.TOS *and* ET4000E.TOS you should have the 
following files:
ET4000/README.TXT                         Guess what!
ET4000/MEGA4000/BAU_ES.TXT                description
ET4000/MEGA4000/BUILD_IT.TXT              description
ET4000/MEGA4000/CARDEK/MEGA4000.PLT       PCB for Cardek-like boards 
                                          (with feature connector, 
                                          these boards can be placed 
                                          more distant from the 
                                          switching PSU)
                                          Scooter format
ET4000/MEGA4000/CARDEK/LTSEITE.IMG       PCB as GEM image file, 300dpi,
                                          not mirrored, soldering side
ET4000/MEGA4000/CARDEK/LTSEITE.LJ3       PCB as Laserjet printerfile,
                                          300dpi, not mirrored, 
                                          soldering side
ET4000/MEGA4000/CARDEK/LTSEITE.LJ6       PCB as Laserjet printerfile,
                                          600dpi, not mirrored, 
                                          soldering side
ET4000/MEGA4000/CARDEK/BSTSEITE.IMG       PCB as GEM image file, 300dpi,
                                          mirrored, components side
ET4000/MEGA4000/CARDEK/BSTSEITE.LJ3       PCB as Laserjet printerfile,
                                          300dpi, mirrored, components 
                                          side
ET4000/MEGA4000/CARDEK/BSTSEITE.LJ6       PCB as Laserjet printerfile,
                                          600dpi, mirrored, components 
                                          side
ET4000/MEGA4000/CARDEK/BSTPLAN.IMG        parts placement as GEM 
                                          image file, both sides,
                                          300dpi, top view
ET4000/MEGA4000/C_MASTER.12+/MEGA4000.PLT PCB for Color Master 12-like 
                                          boards (with feature 
                                          connector, these boards must 
                                          be placed less distant from 
                                          the switching PSU)
                                          Scooter format
ET4000/MEGA4000/C_MASTER.12+/LTSEITE.IMG PCB as GEM image file, 300dpi,
                                          not mirrored, soldering side
ET4000/MEGA4000/C_MASTER.12+/LTSEITE.LJ3 PCB as Laserjet printerfile,
                                          300dpi, not mirrored, 
                                          soldering side
ET4000/MEGA4000/C_MASTER.12+/LTSEITE.LJ6 PCB as Laserjet printerfile,
                                          600dpi, not mirrored, 
                                          soldering side
ET4000/MEGA4000/C_MASTER.12+/BSTSEITE.IMG PCB as GEM image file, 300dpi,
                                          mirrored, components side
ET4000/MEGA4000/C_MASTER.12+/BSTSEITE.LJ3 PCB as Laserjet printerfile,
                                          300dpi, mirrored, components 
                                          side
ET4000/MEGA4000/C_MASTER.12+/BSTSEITE.LJ6 PCB as Laserjet printerfile,
                                          600dpi, mirrored, components 
                                          side
ET4000/MEGA4000/C_MASTER.12+/BSTPLAN.IMG  parts placement as GEM image 
                                          file, both sides, 300dpi, 
                                          top view
                                          
ET4000/ELRAD4K/BAU_ES.TXT                 description (extremely short :-)
ET4000/ELRAD4K/STGAMAIN.PLT               Main PCB (4 layers!) 
                                          Scooter format
ET4000/ELRAD4K/STGAVGA.PLT                ISA PCB
ET4000/HANDBUCH/HANDBUCH.TEX              Dummy file to simplify 
                                          printing of the manual. The 
                                          manual itself is still only 
                                          in German now, sorry! The 
                                          most interesting part is the 
                                          appendix with some technical 
                                          information. I think that's 
                                          useable also for English 
                                          reading people.
ET4000/HANDBUCH/HANDBUCH.DVI              The DVI file...
ET4000/HANDBUCH/BLECH.IMG                 Picture
ET4000/HANDBUCH/ISA-SLOT.IMG              Picture
ET4000/HANDBUCH/MEGAST.IMG                Picture
ET4000/HANDBUCH/STROM.IMG                 Picture
ET4000/HANDBUCH/STUETZE.IMG               Picture
ET4000/1040ADAP/ET40006.PLT               An adaptor PCB for the 
                                          "small" Ataris, (C) P. Lechtenfeld
ET4000/1040ADAP/ET40006.TXT               What do you think...
ET4000/ALT_RAM/MEGA_RAM.PRG               The MEGA4000 as Alternate RAM...
ET4000/ALT_RAM/MEGA_RAM.TXT               Blubb blubb...
ET4000/INIT_MOD/STGAIMOD.MOD              Initializing module for the MEGA4000
ET4000/INIT_MOD/STGAIMOD.TXT              Some copyright stuff...
ET4000/MEGAWVBL/MEGAWVBL.PRG              WVBL program for the MEGA4000
ET4000/MEGAWVBL/MEGAWVBL.TXT              Guess what it is...
ET4000/VMG4000/VMG-4000.PRG               Videomode generator version 1.12
ET4000/VMG4000/VMG-4000.RSC               Resource file for it
ET4000/VMG4000/VMG-4000.CFG               Config. file for MEGA4000 
                                          with Cardek TC ET4000 board
ET4000/VMG4000/VMG-4000.TXT               Manual for the VMG, please 
                                          read carefully!!!
ET4000/VMG4000/VMG-ENGL.RSC               English resource file
ET4000/VMG4000/VMG-ENGL.TXT               English manual
ET4000/VMG4000/HISTORY.TXT
ET4000/VMG4000/SVGA.INF                   Info file with some standard 
                                          resolutions

Videomode generator (VMG)

The VMG is not directly part of this package. Anreas Winter allowed me 
to include it so that you can test the MEGA4000. The included version 
can only be used together with the MEGA4000! I decided to include the 
VMG since to my mind it works quite reliable now and because it's a 
good tool for doing first tests. The included VMG is already 
configured for the MEGA4000 but there are still some things to when 
running the VMG for the first time:
- You should fill in the technical data of your monitor in the 
  Option/Monitor dialog. I've filled in the data for an SVGA monitor. 
  It makes not much sense to work with a monitor which isn't at least 
  capable of displaying the SVGA modes...
- The available dot clock frequencies differ between the different 
  ET4000 boards except for two standard frequencies. The included 
  configuration file is for a "Cardek TC" truecolor board but the file 
  should also work with a Color Master 12+ (a really fine board 
  giving you a crisp picture and having single voltage power supply - 
  but it's not available any more).
  At least it's very difficult now to get an ISA ET4000 board at all. 
  Don't buy ET4000W32 boards!!! NVDI is still not working reliable 
  with these boards. It will still need some time until the blitter of 
  the W32 is supported. So even when you use the Stephan Skrodzki's 
  VoFa II (which is much more complex than the MEGA4000 and already 
  supports the useage of NVDI together with ET4000W32 boards) it's at 
  least slower than the MEGA4000 with an ET4000AX board.
- When you use other boards than the Cardek TC or the Color Master 12(+)
  you must test the available dot clocks of your board 
  (Option/Hardware, Detect Dot Clocks). Depending on the board you may 
  also have to change the CLUT values (Option/Hardware, More Options).
- Important: Check out if the board needs an additional negative power 
  supply! You can get the -12V voltage from the TL497 (voltage 
  converter used for the serial port drivers) but this voltage is not 
  very stable. The picture may flicker when using the serial port. 
  Because there are many revisions of the MEGA ST boards I can't give 
  you more details where to find the negative voltage. Another 
  possibility is to use a MAX232 as negative power supply (I've done 
  that for my Cardek TC board). The MAX232 gives you -10V which is OK 
  for the Cardek TC - at least this voltage is more stable than what 
  the TL497 produces. You find some details about the ISA bus - 
  especially where to apply negative voltages - in the appendix of 
  the German manual. When using the elrad ST version you can get the 
  negative voltage from the backplane if you have installed the 
  "right" power supply.
  Just one hint: When a power supply pin of your board is wired it 
  will be needed in most cases.
- When you really want to use ET4000W32 ISA boards (you have been 
  warned) you will notice errors especially with rasters. I don't know 
  if Till Harbaum's driver software works with the W32. In any case 
  you have to do some additional wiring on the MEGA4000 (see 
  description).
 
Some legal stuff:
GALs and layouts are (C) Torsten Lang (that's me :-).
This project is something between shareware and a commercial product. 
In case of a real shareware project the potential customer must have 
the possibility to test the product before buying it. For the MEGA4000 
it's not possible for different reasons:
- Because of the "very special behaviour" of German shareware users i've 
  included a very restricted version of the GALs. Don't try to hack 
  them - you may damage your computer and/or monitor!
- I fear misuse of my GAL logic by some dealers if I would include the 
  full version. Since GALs can be protected misuse (selling my 
  product whithout paying the shareware fee) is not easy to prove.
- The needed driver software is neither share- nor freeware. At least 
  Till's software is prized within the "shareware region".

The files may only be distributed in form of this unmodified archive. 
Commercial use is stricly forbidden without my written permission. 
Including the files or archives in a PD series also requires my 
written permission. This condition is valid for any of the three 
archives ET4000.TOS (the main archive including the PCBs), ET4000G.TOS 
(including the shar'dware GALs) and ET4000E.TOS (including a first 
attempt of an English documentation). 
  
I take no responsibility for any damage caused by this hardware or 
software. So whatever you do - it's your fault! 

You should check PCBs delivered by me for short circuits etc. This is 
especially important for the +12V line since short circuits will lead 
to serious damage of your hardware! 
When shorting some handshake, address or data lines your hardware 
won't die (normally).

Since the hardware doesn't make sense without software I have to tell 
you what's needed and where to get it:

These archives (ET4000.TOS, ET4000G.TOS, ET4000E.TOS):
- MausNet
- Internet (e.g. on ftp.uni-giessen.de in /pub/atari/...

Graphics boards:
- BWZ Elektronik, Hamburg, Tel.: +49/(0)40/201073
  The available boards are similar to the Color Master 12+ but there 
  are some limitations:
  - The boards need an additional voltage of -12V
  - Up to now the dot clocks are limited to a maximum of 65MHz which 
    is suitable for the following resolutions (X*Y*Colors*Vert.-Freq.):
     800*608*256*98Hz
    1024*768*256*62Hz
     640*480*32K*80Hz
     800*608*32K*52Hz
     640*400*16M*65Hz
     640*480*16M*59Hz
  The board costs around 140DM
  There are also W32 boards for the ISA bus available...
  Some other remarks:
  People there took me for serious even when I told them I needed the 
  board for the Atari (they even checked out some other important 
  things I needed to know)!
- Reichelt Elektronik, Wilhelmshaven, Tel.: +49/(0)4421/26381
  They also have ET4000 boards (ISA) but don't say in their ads if 
  it's hicolor or truecolor. I have no details about these boards.
  The board cost around 150DM
  Other remarks:
  Reichelt normally sells electronics stuff (so you may also get 
  parts needed for the MEGA4000 there) but for some time they also 
  offer PC hardware.

Driver software:
- Till Harbaum, Madamenweg 10, 38118 Braunschweig, Tel.: 0531/83494
  The STGA software supports up to 256 colors, the address range of 
  RAM- and IO-area is not configurable since the software was 
  developed for Till's own graphics adaptor, the STGA. Till has 
  changed the software for me so that it's also running with the 
  MEGA4000 now but he missed some necessary changes. So I've done some 
  patches myself. I cannot distribute this version due to Till's 
  copyright. The STGA software does not use any critical ET4000 
  specific tricks and will also work with critical adaptors. Therefore 
  it may also work with W32 based boards but I haven't tested that.
  The software costs 25DM
- Behne & Behne Systemsoftware GbR, Lindenkamp 2, 31515 Wunstorf 
  NVDI/ET4000 is a very well known software driver for ET4000 based 
  boards but has some bugs. The actual version is V3.02 but it isn't 
  very stable. Especially when using it together with the REDIRECT 
  program I experienced strange crashes when doing some tests for the 
  German distributor of the commercial version of the MEGA4000. So I 
  still work with the very stable version 2.51TC where the truecolor 
  driver has a minor bug. So the V3.xx will still need some time 
  until the most serious bugs are fixed. I also heard of problems 
  (errors) concerning the GDOS implementation of V3.xx.
  The software costs around 140DM
  Remarks: 
  Behne & Behne work on the blitter support for the W32 but this may 
  take a while... 

The MEGA4000 should have been tested by the ST Computer either in 6/95 
or 7/8/95. Until now nothing happened! Since MAXON will drop the ST 
Computer completely at the end of 1995 and do a Mac magazine this 
behaviour is simple to understand.

Questions, suggestions and orders go to:

Dipl.-Phys. Torsten Lang
Pestalozzistr. 9A
61231 Bad Nauheim
Germany
Tel.: +49/(0)6032/87496 (but only if it's really important)
EMail: Torsten.Lang@physik.uni-giessen.de

Please do only send letters to order parts (no EMail, no Fax, no phone)!
