Mystery A500 expansion port splitter

[SpookyAmiga]

Not sure if hardware problems is really the place for this so appologies if not.

I've posted this question on another forum but am hoping to get a bit more info here.

I am currently working on getting together enough bits to rebuild the Amiga system I used to have many years ago. There is one piece of hardware which I don't even know if I will be able to get a hold of, for one I don't even know what it was officially called or who made it!

It was basicly a simple board that plugged into the expansion port on the left side of the A500, it has a passthrough connector so that you could connect something like an A590, which I did. It also had a second connector which was mounted on top of the board, this could be used to plug in an additional expansion port peripheral. I used the second port for my Action Replay.

The closest thing I have found so far is this:

Alfa Data: 86pin Expansion Adaptor
http://www.amiga-hardware.com/showha...cgi?HARDID=709

However I'm fairly sure this is not the same splitter that I had.
The one I had was probably about the same size but the second upward pointing port consisted of another ISA style connector with a short PCB plugged into it rather than soldered on the board and it also sat more central on the passthrough board. I also seem to remember that the lines weren't all directly wired thought as this one seems to be, there may even have been a few capacitors and resistors mounted on it, though I can't be sure about the components.

I realise that the chance of finding either the original I had or the Alfa data board are almost non-existent but I would at least like to find a picture of it and know what it was called and who made it.

Has anyone got any ideas?

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

zipper on amiga.org responded to this question with:
"The splitter was made by Datel, to be used with Action Replay; I had it and used the passthrough for Supraturbo28. Sold 12 years ago :-("

Does anyone else have any further info on this adapter or better still a picture of it? I realise I probably will never get a hold of one, but with some good pictures if theres nothing too special about the board I'd like to have a go at making one from components.

Any info would be appreciated because this is really irritating me now, to the point where I know there were ads for it in some Amiga magazines and I might have to buy a load and find the damn advert

Thanks, Spooky.

[rkauer]

If the board is a Zorro slot adaptor, you check the pinout on pinouts.ru site. Easy to spot the power supply rails and number of pins.

If it is not, the chances are Zipper have the correct answer.

[SpookyAmiga]

It's more of a splitter than an adapter really as it doesn't convert the slot to a different type of slot just gives you two.
Though as this was for use with the Action Replay and also made by Datel I'm unsure if it was wired in any special way or not.

I don't really know enough about the expansion bus and the way it and connected peripherals work. I am a bit puzzled really as if this simply connects everything to the bus in parallel I'd have thought that it wouldn't work, as I know normally you can only have one active piece of hardware on a databus at a time or bad things can happen.

It certainly looks like the Alfa Data adapter/splitter connects everything up in parallel. If that works then I'd be tempted to just make something myself.

[rkauer]

The side expansion slot just uses a twist in a pair of logical lines to attach more than one device.

[SpookyAmiga]

Ah, Ok. That makes some sense. A bit like the method used on OC floppy drives where the last connection has a twist before the connector.
So does that mean you could attach 3 devices to it then?
I am asking that as I was hoping to plug in the A590, Action Replay and a Supra 28 accelerator.

I guess I will have to find time to sit down and study the pinouts properly and read up a bit to get a better understanding of it all.

[prowler]

Hi Spooky,

There is a service manual for the A500+ in the Zone at the moment. It has some schematics in it which might shed some light on the question of connecting more than one device on the expansion port.

When you get in the Zone, scroll down until you reach the file (it's near the bottom). The filename is A500PlusR1.zip.

[SpookyAmiga]

Thanks for the info on that. I didn't even know there was a "zone"
Unfortunately I don't seem to have permission to access it. Is there a requirement with number of forum posts to be able to get on? I have done the activation process from the email sent to me when I first signed up.

[Graham Humphrey]

Check out the 'Rules & Help' link at the top of the forum.

[SpookyAmiga]

Sorry ignore that. Just found out what to do. Should explore more first and ask later