reverse engineering apple II interface cards - general thread

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speedyG's picture
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reverse engineering apple II interface cards - general thread

In another thread specific related to the wildcard the idea was given to start a general thread...

Hello all together,
instead of starting discussion about which task has priority....
probably it might be more interesting to instead treat this thread as a kind of "wish-list"
or also as "planning task list" - checking out which cards should come on the list,
find out which cards are completely availiable with hard- and software and documentation -
to find out if reengineering is possible .....

and then create/join groups to solve the task ( similar to the moutain expansion box )

and then open for each card on which reengineering will be done an own thread ....

i guess that when the task / i.e. thread for a card is started - in that thread it can be found out,
if there is enough interest to start a "run" or if just the documentation of the reengineering is done -

if there is not enough interest for a "run" and then just publish the gerberfiles to permit those,
who are interested to order with that data a single ( but much more expensive ) prototype board order at a PCB-manufacturer...

if there is not enough interest then there won´t be enough people joining for the task of reengineering and
that card will be anyhow "dead" and kicked off the tasklist because it won´t turn to an own thread....

and if there are enough persons for a "run " - then it´s a part of the task within that single thread to collect orders, get the ( cheaper because more cards being ordered ) "run" from a PCB-manufacturer organized and then solve the orders....

if i would for example do the task on the IIe diagnosis card i´d expect rather only people with several IIe´s or local user-groups with IIe owners to be interested for getting a card, because that would permit to do better and faster service on the units....

just a proposal....
sincerely speedyG

in that thread also the following was posted by mutant pie:

As a general idea to throw out there, in my opinion two of the more interesting and hard to get cards for the Apple II were the Apple issued Video Overlay card, and the Computer Eyes video signal (still image) digitizing card. I have the second one (software and manual), and know that at least one other 'Fritter member would like to have one.

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Re: reverse engineering apple II interface cards - general ...

Couple of custom chips on the Video Overlay Card. There's a MEGA II. And, I believe, an FPGA that configures itself at each power-up.

I probably have a scrap Video Overlay board that could be torn down and x-rayed (multi-layer I think). Then I've got a pristine NIB unit which could not be made available for re-engineering.

I also have a Computer Eyes board, NIB, and one to play with. IIRC, this is all standard stuff, nothing custom..??

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Re: reverse engineering apple II interface cards - general ...

ooops .... bouncing key...

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Re: reverse engineering apple II interface cards - general ...

Hello to all AF-members,

if the desired card contains LSI-chips ( LSI=Large scale Integration ) like Mega II or similar -
well then a reverse engineering is nearly impossible.....
in former days such "custom chips" have been made on demand - and after they have been manufactured - the ordering
company got the entire stuff ( shematics and production data ) back to protect the ordering company from "copy cats"...

if such chips contained read-protect-fuses they normally have been blown in production to make it impossible to read-out
logic tables.... this is quite similar to the PAL´s used in a lot cards ( like PAL18V6 or similar ) .... only in very few cases such read-protection-fuses have been forgotten to blow...... such chips only can be read if the fuse is intact and read-out is still permitted....

sincerely speedyG

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Re: reverse engineering apple II interface cards - general ...

Hello to all AF members,

at the end of April after VCFe has passed by i´m starting to reverse engineer the Apple //e Diagnostic Rom Card.
This card was used by dealers and service technicians to make fast diagnostic on Apple //e systems.
It contained a diagnostic programm in Eproms and was able to uncover nearly every problem known by the Apple IIe.
It has never been released to the public and therefor only very few of this cards have been made.....
but it has for sure quite a large value for larger user communities and local user groups or collectors with
larger amount of IIe computers in their collection for assisting their local staff by maintaining the members computers.....

i´ll therefor perform a reverse engineering task on this card and publish the information here in an own thread....

here at first step a view on the top and solderside of the card:
the topside:

and the bottomside:

sincerely speedyG

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Re: reverse engineering apple II interface cards - general ...

This is an old thread but....
So, how have you made out with the Diag Board?
I think a Thread like this would be fun. I am in the middle of reverse engineering the SCRG Quickloader myself. I am trying to get it on a smaller board with 5 instead of 8 eproms. That size board is less expensive to produce. I feel I have the schematic correct but routing is the problem on the smaller board. I hope you have had success on your Diag Board. I have one so if you need to look at a different board let me know. Wish me luck on the Quickloader.
wm

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Re: reverse engineering apple II interface cards - general ...

Hi wment,

I have a collection of QuikLoader boards, but I have an even smaller collection of
pre-programmed applications (EProms) for them. I can burn EProms without issue but taking the time to
make up applications is time consuming. I suppose when I retire, I can do better with that.

I'm more than happy to share the EProm sets that I have. Would you do the same?
Also, why do you want to reduce the count of Roms down from 8 to 5? Is it only for reducing the board size?
You can likely reduce the board size if you use surface mount ICs for the logic and make the EProms 2 rows of 4.
Let me know if you need help on that.

One of my ambitions is to reverse engineer the WildCard Pro, the version with the microprocessor on the board.
Can't seem to find anyone willing to sell or rent one of those. Sad

Let me know on the QuikLoader EProms... Thankx!

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Re: reverse engineering apple II interface cards - general ...

Hi
Yes the reduction from 8 to 5 was so I could get it on a 100mmx100mm board in Eagle. I got the physical parts to fit but not the routing, not enough space but not giving up. Even using SMT I was not able to get everything on the 100mm boards. The 100mm boards are less expensive to produce also. Since my last post I have completed (I think at this point) the routing for the 8 chip board and almost ready for a PCB quote. I will continue exploring with the SMTs. Using SMTs will require many more VIAs to get signals between layers. My eprom collection is very basic but will be happy to share.

How have you made out with the Diag Cards?

wm

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