Date   : Wed, 27 Oct 2010 21:31:24 -0500
From   : jules.richardson99@... (Jules Richardson)
Subject: Reversing the Tube ULA (destructively)

J.G.Harston wrote:
> John Kortink wrote:
>> Yes. But properly implementing nDACK can be more involved
>> (depending on the logic chip) due to timing issues. Maybe
>> the ARM evaluation system uses it.
> 
> No, tied to +5v.

Ditto for the 80286 copro.

The interesting ones might be the Springboards (can't tell from my photos, 
sadly - I never took snaps of the underside of the boards) and the A500 "copro 
version" as they may have done things differently.

cheers

Jules