Intel 3000 series

dwight dkelvey at
Fri May 4 22:36:49 CDT 2018

As Allison says, some other controller would be a lot easier to deal with. The 3000 controller was intended for speed.

I knew the fellow that wrote the code for the M2FM controller while at Intel ( Lou Bolardo sp? ).  He was not my kind of person ( we never got along ) but he was one of the smartest people I have ever met.


From: cctalk <cctalk-bounces at> on behalf of allison via cctalk <cctalk at>
Sent: Friday, May 4, 2018 7:40:18 PM
To: cctalk at
Subject: Re: Intel 3000 series

On 05/04/2018 09:16 PM, dwight via cctalk wrote:
> I'm not sure how much good a 2900 assembler would be for a 3000 series part. The 2900 has an address controller more like a typical micro computer, while the 3000 is more like playing a game of chess.
There seems to be the presumption the bit slices have a uniform organization
like a micro.  They generally don not.  The opcodes and micro code are
and created by the developer and their minions along the lines of some
architecture they wish to create.  they tend to have a pattern and thats
about it.

The 2900 has an address controller if you used the 2910 or 2911, no rule
says you must.
Random logic an be used.

The 3000 series was very similar only 2 bits wide.  I haven't seen one
of 40 years but likely
have the book somewhere.  I think the only thing I've seen them in was
the MDS-800
Disks system (the DD one).

They all (don't forget the 6300 series) are similar, an alu not unlike
the 74181, some glue
and muxes for bus organization and few (usually 16) registers you can
use how you wish,

In the end they are all microprogrammed and the architecture is very
fluid well beyond the
slice width.  Even the order of control bit fields is up to the designer
and can even be vertically
encoded for systems with narrow microstore.
> Of course, you can always use 3000 series alu's with a 2900 series address controller ( 2910 or 2911 as I recall ).
Also depending on which you use the bit assignments, stacks, available
temp registers are not identical.

I've done that using 74157 muxes and 163 synchronous counters  even had
conditional micro jumps.
Made my own assembler written in Pascal.    Never had commercial one
available to me.


> Dwight
> ________________________________
> From: cctalk <cctalk-bounces at> on behalf of Eric Smith via cctalk <cctalk at>
> Sent: Friday, May 4, 2018 1:40:17 PM
> To: Kyle Owen
> Cc: General Discussion: On-Topic and Off-Topic Posts
> Subject: Re: Intel 3000 series
> On Fri, May 4, 2018 at 2:10 PM, Kyle Owen <kylevowen at> wrote:
>> I assume it's one of these?
> Any tips on how to get it running in SimH or the like? I don't see any text
>> file describing the system or format.
> Should be in there somewhere. The IMD files are ImageDisk format. The ZIP
> files contain the extracted CP/M files.  I ran it some years ago but don't
> recall the details.
> Some time ago I started working on an AMDASM clone written in Python 3, but
>>> it's not yet far enough along to be useful.
>> Sweet! I wonder if there is enough in the way of microcoded stuff that a
>> microdisassembler wouldn't be handy as well. Does something like that
>> already exist?
> I haven't heard of a general-purpose microcode disassembler. I wrote a
> custom disassembler for the Atari Am2900-based "Math Box" used in
> Battlezone, Red Baron, and Tempest, and a few others for even more obscure
> machines.

More information about the cctech mailing list