@BEGIN_FILE_ID.DIZHow to make your A1200 into a Tower! Good!
@END_FILE_ID.DIZ

               AMIGA 1200Tower (Or Table version up to you)

Here you will get instructions of a solution how to install an Amiga 1200
In a PC Towerbox or Tablebox.. it's all up to you.


This is QUITE simple electronics but if you are not used to electronics
let someone else do this for you.

I take *NO* responsability if anything goes wrong (specifications changes
or whatever) and destrys your computer. I have done as told in THIS text
on my OWN Amiga 1200 with a fine result.

Please BEFORE buying a box check if the PCB actually DOES fit..
I wanted a Mini-Tower but the Mini-Towers I checked was far too small.

---------------------------------------------------------------------------

Harddrisk problem:

If you want to use expensive and SLOW 2 1/2" harddrives you can skip
this part.  This describes how to connect a 3 1/2" harddrive to an A1200.

I will include the specifications of the IDE cables:

    The pinouts are as follows:  (_NAME means signal active low)

    Name      2.5"   3.5"    Desc
    _RESET  |   1  |   1  |  Drive reset
    GROUND  |   2  |   2  |
    DD7     |   3  |   3  |  Drive data bus bit 7
    DD8     |   4  |   4  |  Drive data bus bit 8
    DD6     |   5  |   5  |  Drive data bus bit 6
    DD9     |   6  |   6  |  Drive data bus bit 9
    DD5     |   7  |   7  |  Drive data bus bit 5
    DD10    |   8  |   8  |  Drive data bus bit 10
    DD4     |   9  |   9  |  Drive data bus bit 4
    DD11    |  10  |  10  |  Drive data bus bit 11
    DD3     |  11  |  11  |  Drive data bus bit 3
    DD12    |  12  |  12  |  Drive data bus bit 12
    DD2     |  13  |  13  |  Drive data bus bit 2
    DD13    |  14  |  14  |  Drive data bus bit 13
    DD1     |  15  |  15  |  Drive data bus bit 1
    DD14    |  16  |  16  |  Drive data bus bit 14
    DD0     |  17  |  17  |  Drive data bus bit 0
    DD15    |  18  |  18  |  Drive data bus bit 15
    GROUND  |  19  |  19  |
    key     |  20  |  20  |  Key for interface connector
    DMARQ   |  21  |  21  |  DMA request (not supported yet)
    GROUND  |  22  |  22  |
    _DIOW   |  23  |  23  |  Drive I/O write
    GROUND  |  24  |  24  |
    _DIOR   |  25  |  25  |  Drive I/O read
    GROUND  |  26  |  26  |
    IORDY   |  27  |  27  |  I/O channel ready
    SPSYNC  |  28  |  28  |  Spindle sync (not supported yet)
    _DMACK  |  29  |  29  |  DMA acknowledge (not supported yet)
    GROUND  |  30  |  30  |
    INTRQ   |  31  |  31  |  Drive interrupt
    _IOCS16 |  32  |  32  |  Drive 16 bit I/O
    DA1     |  33  |  33  |  Drive address bus bit 1
    _PDIAG  |  34  |  34  |  Passed diagnostics
    DA0     |  35  |  35  |  Drive address bus bit 0
    DA2     |  36  |  36  |  Drive address bus bit 2
    _CS1FX  |  37  |  37  |  Chip select 0
    _CS3FX  |  38  |  38  |  Chip select 1
    _DASP   |  39  |  39  |  Drive active/slave present
    GROUND  |  40  |  40  |
    +5v     |  41  |  --  |  +5v supply
    +5v     |  42  |  --  |  +5v supply
    GROUND  |  43  |  --  |
    RESERVED|  44  |  --  |  Reserved for future definition





As you can see the difference between a 2 1/2" and a 3 1/2" cable is that
the 2 1/2" cable contains +5V power aswell..  so you simply just BUY one
of those 3 1/2" -> 2 1/2" adapters or make one yourself.

It's quite simple to make the cable.  buy a 2 1/2" cable and one 3 1/2" cable
cut the cables in half..  solder pin 1 from the 2 1/2" cable to pin 1 of the
3 1/2" cable, then pin 2 etc etc until you have done 40 of them.. now you
are finished. (you can skip the last 4 on the 2 1/2" cable)

the power is easyest to take from the powersupply in your box. if you still
want's to use power from your Amiga them take it from the diskdrive:

 Diskdrive power connector in the computer:
 
    ---- <- A protection in your 1200 so you cant turn the contact WRONG
    1234                  1=+5V      2 och 3 = GND    4=+12V
  
  
 The HD Contact:
    ______ 
   |      |
   | 1234 |               1 = +12V   2 och 3 = GND    4 = +5V
    \____/
 
 

Now that is done..  if you want a HD cable for TWO IDE drives (you know
you can connect 2 IDE drives on the same controller) you just have two
40 pin IDE connectors on the cable!  no twistings etc.  and set the
last drive in SLAVE mode. (se documentitations for your HD about this)

---------------------------------------------------------------------------

Keyboard problem:

This is the biggest problem when doing this is to get a nice BOX.. I was
lucky and got hold of an old Amiga 2000 keyboard.

You will NEED:

a Keyboardcontroller for the Amiga 500.

Connect the A500-Keyboard controller to the A1200 keyboard cable now you
solder a cable from the controller that contains:

Pin   Action

  1   _KBDATA
  2   _KBCLOCK
  3   _KBRESET
  4   +5V
  7   GND

the rest is not needed (you can unsolder the leds) now you must connect those
signals to the Amiga 1200.

Find the 8520 (surface mounted) and get pin 42 and 43 (counted from 0)   its
found at: (It's the 8520 mounted closest to the keyboard connector)

                 _________________________
                |                         |
                |                         |
                |                         |
                |                         |
                |                         |
                |                         |
                |                         |
                |                         |
                |         8520            |
                |                         |
                |                         |
                |                         |
                |                         |
                |                         |
                |                         |
                |                         | etc
                |                         | 6
                |                         | 5
                |_________________________| 4
                           ^^^
                           ||0  1  2  3  etc tec
                           ||
                           ||_Pin 43
                           |
                           |__Pin 42

As you can see pin 42 and 43 is the LAST pins on the 8520..

Now solder _KBDATA to pin 42 and _KBCLOCK to pin 43  (if you do connect
those wrong the computer will pump out a shitload of crapchars!  change
the pins and it will work)

_KBRESET must be soldered to pin 128 in the internal trapdoor (where
32 bit memorycards etc are mounted)

now you got a nice external keyboard for your 1200..


AND!!!!!!!! the annoying pause between "the-magic-three-ones" and the reset
is GONE.

Several Towerboxes have switces for "RESET" just connect _KBRESET to GND
and your computer will reset.


I tried with the Keyboard controller from the A2000 but it didn't work.
I think it must be cauze of the handling of the RESET signal differs on
A2000/3000 etc compared to A500.

-----------------------------------------------------------------------------

Bonus hacks:

Level 7 IRQ, this can be nice if you want to make a program that starts when
             a special button is pressed.
             Or if you want to use the LEVEL7 RESQUE function in Trash-em one
             etc.  or want a temporary Halt.

Get three diods. solder them to pin 81, 82 and 83 in the trapdoor
( _IPL signal) and at the other end of the diods you solder them together to
ONE point. when this signal is grounded the Level 7 IRQ is made.

CPU HALT, This completly freezes the computer.
          Just Connect pin 86 in the trapdoor ( _HLT) to ground.  this will
          freeze the computer.



A tip to make this on a good way is to connect all wires to a internal contact
so if you want to you can remove the PCB and still not have to unsolder a lot
of wires.  I used a 25 pin D-Sub for this and configurated the pins like this:

          1 _KBDATA
          2 _KBCLOCK
          3 _KBRESET
          4 +5V
          5 GND
          6 N/A
          7 +12V
          8 DISKDRIVE (Led-Board from the A1200)
          9 +5V (from the LED-board)
          10 POWER LED (from the Led-Board)
          11 _HLT
          12 HARDDISK LED (from the Led-Board)
          13 Lev 7 IRQ
          14-25 GND


So now im completely free to remove the A1200 PCB whenever I want to.

Ok how to get the parallel, serial etc connectors to the outside? there are
TWO ways of doing this: one not expensive and one expensive way.

first the LOW-priced one:

unsolder all connectors solder a ribboncable (like the IDE cable) to them
and mount them on the box.

this is not a very good solution but doesn't cost THAT much. but it's easy to
get poroblems etc later on.

the EXPENSIVE way: (but MUCH better)

Get two connectors of each contact one in male and one femal gender. the BEST
is for ribboncable.. and do cables of this..  now you doesn't have so solder
so much on the Amiga PCB and the risc for destroying your computer is
minimized.

I will enclose a list for the contacts and the order number for ELFA in Sweden:

9Pin  D-Sub Male Ribboncable       43-669-02
9Pin  D-Sub Female Ribboncable     43-669-10
15Pin HDD-Sub Female for soldering 44-071-28 (for the VGA/MS monitor)
23Pin D-Sub Male for soldering     44-058-41
23Pin D-Sub Female for soldering   44-058-90
25Pin D-Sub Male for ribboncable   43-669-69
25Pin D-Sub Female for ribboncable 43-669-51
RCA Double Chassimontage Female    42-252-15 (for Audio/Video etc)
RCA SINGLE Male                    42-259-00
5Pin DIN ChassiMontage             42-206-04 (Keyboard connector)

Cables:

24Pin 55-660-88 (Monitor, Diskdrive)
25Pin 55-660-62 (Parallel, Serial)
9 Pin 55-660-05 (Joystick, Mouse)
15Pin 55-660-47 (VGA/Multisync monitor)
40Pin 55-661-38 (IDE Harddrive)

IDE Connector (3 1/2" version dunno abt 2 1/2") 43-646-67

I actually forgot to order cable etc for the diskdrive so you have to find
that yourself. :)  The diskdrive have 34 Pins.



Please DOUBLECHECK everything before turning ON your computer.. and enjoy your
Amiga 1200Tower.


I still havent solved how to use Zorro II or III cards in the A1200. If you
know how to do that PLEASE contact me ASAP.


Ways of contacting me:

Fidonet: 2:203/603.53 John Hertell
BBS: +46 (0)554-12133 US Robotics V32Terbo/ASL/DualStandard/FAX 9600-21600 BPS
Voice: +46 (0)554-40403 (Between 18:00-23:00 Swedish time)
Snail: John Hertell
       Hckgatan 3
       665 32 Kil
       Sweden


I must send out some thanx for helping me with this thing:

Jetfire (Stefan Johannesdal):
        He helped me to find the _KBCLOCK and _KBDATA signal with the help of
        his ocilloscope..  too bad the A2000 board didn't work on the A1200.
        it SURE bugged us when we tested it.

Core/TRSI:
        For selling his broke A2000 keyboard to me..  that one took me THREE
        HOURS to fix.. what have you DONE with the keyboard man? :)

MR AGA:
        For finding the ELFA Order-codes for contacts and cables etc.
        AND for finding that my powersupply WASN'T broke  it just didn't
        startup if the equipment connected to it didn't use enough power.
        (a tip for all you guys there having the problem that the supply
         just turns OFF after one secound, but one A1200 and HD did the thing)

SOFTSENSE in Karlstad:
        Actually just for selling me the Maxi-Tower box with powersupply for
        just 400SEK..  But i SURE doesn't like their attitude..

and everyone in fidonet that have come up with ideas how to solve the
keyboard problem. ( AMIGASVHARD )


Happy soldering                      Chucky of Virtual  SYSOP at GANGBANG BBS
 
