How does autoconfig actually work?

[ReadOnlyCat]

Originally Posted by TroyWilkins

I know this is offtopic here, so I'll keep it brief, but that makes me think of SIO on the (Yes, I know, but they are the direct ancestors to the Amiga) Atari 8-bit machines - 400/800 etc - and how it isn't a billion miles different in some aspects to what we now have in USB...

A certain Jay Miner kitten happens to have been a hardware engineer both for the Atari 8 bit and the Amiga. The ressemblance is definitely not coincidental.

Originally Posted by thebajaguy

On the hardware side, the A500/1000 86-pin edge expansion connectors Config-out signals are grounded, making them auto-config enable signaled to what is connected. The 86-pin CPU slot of the A2000 has it's config input grounded much the same, making it first active, if present, at $E80000, and when done hands it off to the expansion slot logic. The A2000 Rev 6.2 schematics, page 7 (expansion bus), U606 at the top, then have all of the AutoConfig signal In/Out circuitry going through it on each slot's pins 12 and 11 of the various 100-pin expansion slots.

Yup, it is entirely possible to convert the 86 pin expansion slot of the A500 into a full multi-board one provided that the autoconfig routing is handled properly, of course this requires additional circuitry (on the added board, not in the Amiga) so this was rarely done but there are a few expansions which provide this.

The Bodega bay is one of these if I remember correctly (http://www.bigbookofamigahardware.co...t.aspx?id=1362), I saw one on eBay a few years ago but alas it was snatched away before I got a chance at it.

[Daedalus]

Thanks Toni, that makes sense

[idrougge]

Originally Posted by thebajaguy

As far as I recall (and I am talking as far back as my GVP Tech support era 1989-1993), a board that already has a driver from a ROM won't be affected by a SYS:Expansion driver activated by Bindrivers - i.e. during startup. I can't recall any board I ever encountered from 3rd party or C= offerings in that one driver replaced another this way.

Oktapussy does that for Oktagon/BSC/Alfadata controllers.

[TroyWilkins]

Originally Posted by ReadOnlyCat

A certain Jay Miner kitten happens to have been a hardware engineer both for the Atari 8 bit and the Amiga. The ressemblance is definitely not coincidental.

Oh yes, I'm well aware of that, however SIO nor USB were on any "classic" Amiga hardware released by Commodore. I was referring to the Atari 8-bit SIO bus, not the shared design philosophy of the custom chips at the heart of the Atari 8-bit and Amiga machines.

[thebajaguy]

Originally Posted by idrougge

Oktapussy does that for Oktagon/BSC/Alfadata controllers.

I was USA-based, and out of the GVP Tech Support business by March 1993 for the first round of 'thinning the ranks'. Oktagon and the others were from across the puddle, and we tended not to encounter much overseas-developed hardware. The distributors which supported in their local language likely did. I kind of recall Alfa from back then, and years later do recall Oktagon as I looked up hardware on the BBoAH and Amiga Resource sites. I'm thinking I never encountered the hardware in a support capacity.