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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Generale on March 07, 2005, 02:47:37 AM

Title: A500 BUS connector pinout problem...
Post by: Generale on March 07, 2005, 02:47:37 AM

Hey there!

I've been plodding away building the a500IDE on aminet, and I came across something which confuses me.

The pinout listed for the A500 buss connector. I look at the mainboard on the A500 and the pinout given in the doc seems to be a mirror image. Is this so?
What I mean is that the wide contact with the earths is on the left when looking at the A500 and not the right....right?
The top and bottom I assume are correct.

The only reason I'm asking is taht I'm having a terrible time finding another bus pinout or an a500 schematic.

Any help would be appreciated.
Thanks all.

Title: Re: A500 BUS connector pinout problem...
Post by: AmigaEd on March 07, 2005, 03:42:05 AM

It seems to me that I remember something about the A500 interface being inverted from that of the A1000. That may make sense since the port on the A500 is on the left and on the right on the A1000. Perhaps the drawings you are looking at are for the A1000?

I beleive that I've seen posts on here about this interface in the past. Maybe try searching for A500IDE?

Just a few thoughts...

-AmigaEd

Title: Re: A500 BUS connector pinout problem...
Post by: clockmstr on March 07, 2005, 11:24:13 PM

The pinouts of the A500 bus connector are pin 1 closest to Denise to pin 85 at the other end, usually marked on the motherboard. The pin numbers alternate from top to bottom from pin 1 to pin 86, with all uneven numbered pins on top and uneven numbered pins at the bottom.

Pins 1 - 4 are all earthed, that is the first two upper and lower pins on the connector, closest to Denise.

If you have the A500 schematics then you should have each pin assignment, if not either download them from my old site http://www.whirljack.net/jeremy/clockmeister/ or email me at clockmeister at internode dot on dot net and I'll help you with your project.

My interface that can be seen in the images section on amiga.org borrows heavily from the A500IDE project, in particular the first prototype.

Hope this helps :-)
 

Title: Re: A500 BUS connector pinout problem...
Post by: Generale on March 10, 2005, 08:23:37 AM

Woot!!
Thanks for that! I didn't have the schematics.
Sorry this reply took so long. My computer was eaten by maggots or something. Had to reinstall from scratch anyway.

Thanks for that!