> From: Tony Duell <ard_at_p850ug1.demon.co.uk>
<> >Any other AM29xx chips on it, like a 2909 or 2910 sequencer? Or is this
<> >just a demo board for a 4-bit ALU chip?
<> >
<> >It sounds like a really interesting find, though. The 29xx series chips
<> >were interesting devices that have been used in all sorts of machines.
<>
<>
<> Yep, there is a 2909 on board too....
<
<Ah, so there's a sequencer. And presumably, therefore, there's some kind
<of control store (ROM or RAM) on the output of that. So it sounds like
<it's a complete processor, albeit a small one.
How small depends on the microcode. It could easily be PDP8 or Nova
emulation with one 2901 though it would be slow. I've seen at one commercal
design that use it as a fast version of TMS1000 4bitter.
It's an interesting chip. I have a bunch of the raw 2901C and 2911 parts.
One day when I have time I'd like to try an extended wordlength PDP-8 like
machine using them. Say something obcenely long like 20 or 32bits. After
all working with that chip 8bits or 80 is as easy from the microcode
perspective. Besides it's the microcontroller that is the complex part.
Allison
Received on Sun Feb 27 2000 - 13:26:16 GMT