@DATABASE
@NODE MAIN "Drive Solution for news A1200/A4000T            ©1997 Mauro Lourenço"


                           @{b}PC HD Drive Solution@{ub}

                           @{fg shine}©1997 Mauro Lourenço@{fg text}


 
                @{"    Warning     " LINK Warning}     Danger! Pay attention!
                @{"    History     " LINK History}     Why I do it?
                @{"     A4000T     " LINK A4000T}     You should be careful!!
                @{"Schemes & Images" LINK Schemes}     The mine map!
                @{"Another solution" LINK Another}     If it is more easy to you....
                @{"     Author     " LINK Author}     Any doubt, contact me.
@ENDNODE
@NODE Warning


           @{i} *** WARNING *** WARNING *** WARNING *** WARNING ***@{ui}


Only expert technicians should be able to make changes! If you are just a
curious...take care with your A1200/A4000T! 

Note: This solution is to do PC HD drive work like DF0 DD drive only on
      new A1200/A4000T from Amiga Technologies!

@ENDNODE
@NODE History


                    @{i} A little and beautiful history...@{ui}

My friend Frank Hoffmann (http://www.nitnet.com.br/~hoffmann) bought an
A1200 (made in French) at England and he had a problem:  the drive didn't
work with NDOS games and softwares like X-Copy.

I oppened the A1200 and I saw that the drive was a PC HD type.  The pin 34
was connected with pin 2 because the actual drives don't use READY signal
anymore and the DISKCHANGE now is on pin 34.  So, Amiga Technologies (actual
Amiga International??  - GO GO GO Gateway!!) changed the connections on the
A1200 board and not on the drive cable or on the drive.

So I solved make two changes and "manufacture" a READY signal but what is
it?  READY signal appears 0.5 sec after the MOTOR ON signal on pin 16 goes
to down level and it means that the drive informs to interface that it is
"ready" to do reads or writes operations.  Well, I thought that the actual
drives are faster than older ones and I solved just to switch the pins 16
and 2 at same time.  I decided to put a germanium diode like 1N60 type
between MOTOR ON and READY. I saw that is safer put it on drive soldering
it on the pins 16 and 2. You can use others replacement germanium types but
don't use Silicon ones! There are several types like AA113, AA118, OA90,
1N34, 1N93 that can be tested.

Results: the drive worked fine! The NDOS games and X-Copy ran!

@ENDNODE
@NODE A4000T


               @{i} You can make changes on A4000T board too...@{ui}

Some A4000T has a PC HD working as DD drive.  These schematics are valid to
it but the cuts on the board maybe not.  Take a look if any other connection
is near of the pins 2 and 34 from drive board connector.

@ENDNODE
@NODE Schemes


                          @{i} The solution is here!@{ui}

Original scheme from @{"Commodore" system "run >NIL: multiview commodore.iff"}, @{"AT" system "run >NIL: multiview AT.iff"} and my @{"solution" system "run >NIL: multiview solution.iff"}. You also can see the
images below (256 colors) with a viewer program:

@{"Connectors" system "run >NIL: multiview Connectors.iff"} - See the cuts made by AT and me. Try to find them on your
              board using an ohmmeter. Both are narrow cuts.

@{"Wires" system "run >NIL: multiview Wires.iff"} - See the wires to change READY <-> DISKCHANGE pins. I profit the
         brown wire from AT and I add on another white. The brown wire
         was connected between pins 2 and 34.

@ENDNODE
@NODE Another


                         @{i} Try this if you want...@{ui}

Two options:

1)
If your drive was a Panasonic JU257A 605P you can try to make changes on it.
Back to the original scheme from @{"Commodore" system "run >NIL: multiview commodore.iff"} connecting the brown wire
between pin 34 of CN11 connector and pin 1 of drive DB23 connector and get
the Bruce Abbott's file ju257.lha from Aminet hard/hack dir to learn to make
changes on drive.

2)
You can back to the original like above and change pins 2 and 34 on the
drive making cuts and put the diode on it board like my solution.

Note: There is another solution on Aminet from Christian Sauer's file
      A1200FDfix.lha but you will have to mount a circuit on a PCB.

@ENDNODE
@NODE Author


                                 @{i} Well...@{ui}

If anything doesn't appear ok for you or if you didn't understand nothing so
write me:

Mauro Sergio Lourenço

email: lourenco@urbi.com.br

Mail:  Rua João Pessoa, 361 - Icaraí
       Niterói - RJ
       Brasil
       CEP 24220-330

20-April-97
@ENDNODE