Intel 4004 simulator and tools

From: Dwight Elvey <elvey_at_hal.com>
Date: Tue Feb 9 19:36:06 1999

Doug <doug_at_blinkenlights.com> wrote:
> On Tue, 9 Feb 1999, Dwight Elvey wrote:
>
> > The simulator was specifically setup for the SIM4-01
> > board but could be easily modified for most any hardware.
>
> Hi, Dwight.
>
> Could you give us more info about the SIM4 board? I've always been
> somewhat confused by Intel's naming conventions, and since this is a very
> historically significant computer, I want to understand what's what.
>
> Here's what I *think* I understand:
>
> Intel made the 4004 CPU in 1971 as part of a complete computer chip set
> called the MCS-4 (MCS = Micro Computer Set). They also created a few
> computer systems around the MCS-4, including
> * the Intellec-4, a full fledged system with front-panel
> * the SIM-4, a single-board computer for evaluation
>
> Did they make any others? I think there were variations of the SIM-4,
> right? Dates?

Hi Doug
 The SIM4-01 was made to take 4 1702's for program ROMs and
had 4 4002 RAM chips. The board had simulated I/O to act like
the I/O that came on the 4001 mask ROM chips. There was also
a SIM4-02 board that could take up to sixteen PROMs and had
sixteen 4002 RAM chips. The MCS-4 chip set originally included
4004 ( uP ), 4001 ( Mask ROM and 4 I/O pins ) and the 4002
( RAM and 4 Outputs ). Later additions were the 4003 ( Serial/Parallel
I/O ) and 4008/4009 ( TTL level converters ).
 The Intellec-4 was made later. The Intellec-4 was soon replaced with
the Intellec-4/40 that used the newer 4040 version of the
4004. They were bus compatible. When I was at Intel, I think
we were the last to use the 4040's in our UPP ( Universal Prom
Programmer ).
 The 4004 used a Harvard architecture and had some what of a restricted
instruction set. It didn't even include such things as bitwise
AND and OR. These had to be generated by using the add instruction
and built a bit at a time. The adder at a bit location is
the XOR of the bits and the carry generated is the AND of
the bits.
 The SIM4-01 usually came with a back plane board called the
MCB-4 and a PROM programmer card called MP7-0x. Depending on
revision, it was designed to program 1702, 1602, 1701, 1601
and later versions did 1702A's. It should also be noted that,
as I recall, Intel also made the first EPROMs. The SIM4-01 board
came with 3 PROM's with code to program the PROMs. The board, using the I/O
space of the ROM's and RAM's, had a 20ma current loop serial.
Luckily they were using ASCII instead of Baudit in those
days. I made a simple RS232 interface to convert to my
PC at 110 Baud. I'll try to get a picture up on my
web page for show and tell.
 Intel originally made the 4004 for a company call Busicom.
It was to be used in one of their calculators. It was
dropped in favor of a dedicated calculator chip but
as we know, many applications were just waiting for the
uP to happen.
 I'm not sure of all the dates but the 4004 was introduced
in 1971. My SIM4-01 board has all the date codes in 1972.
 Many think that the 8008 was the first 8 bit uP but
Fairchild was first with a two chip F8 by a small margin.
 Wow, I feel old. I remember reading about the 8008 when
it first came out.
Dwight
Received on Tue Feb 09 1999 - 19:36:06 GMT