Most recent revision dated Nov 19 2007. Previously this document was "isis.txt". Here's a link to the old document. (c)Copyright Herb Johnson 2007 except as quoted remarks.
This document describes the earliest Intel 8-bit development systems and their software. There's also information about subsequent ownership of these products after Intel sold off the rights; and Web links to sites with more information and software.
In the early 1970's, Intel offered a hardware development system which used the 4040 processor on a proprietary set of (non-Multibus) Intel cards to operate a paper-tape and PROM based system for 4004 and 4040 development, called the "Intellec 4" for the 4004,and the "Intellect 4/MOD 40" for the 4040. Details are described in a section below. Later, there was an 8008 version and an 8080 version, the "Intellec 8" and "Intellec 8 mod 80".
At some point ISIS, a floppy disk based OS, was available for the 8080 on the Intellect 8/MOD 80 system. Versions of the ISIS OS also ran on their subsequent Multibus-based, 8080-based "Intellec MDS" system, followed by their 8086 based systems. The programming language PL/M supported only the 8008 and 8080 and is also described in this and related Web pages. iRMX, not described here, was a later Intel real-time operating system which ran on Intel processors and Multibus cards.
Dr. Gary Kildall, who founded Digital Research in 1975 to promote CP/M, provided many of Intel's 8008 and 8080 software products including the PL/M compiler and cross-assemblers, which were written in FORTRAN. The earliest CP/M's had a BIOS for use with a Intel 8080 Multibus system. Intel turned down Gary Kildall's offer of what became CP/M. Further discussion of Gary Kildall and PL/M and CP/M is on my DRI Web page and other pages linked from it.
I have a substantial Multibus card and document collection. (But I'd like to get pre-Multibus Intel products and info, let me know if you have them!)
Details about these early development products are difficult to find in the 21st century, because Intel never marketed them except as development systems, so published
accounts of the period are limited to trade magazines and conference papers and Intel manuals.
(Intel offered a simple 8008 development system in 1972, using a 8008 processor and
memory board called "SIM8-01" inserted into a motherboard (possibly called "MP7-02") with lights, switches and a power supply. A 4004 model was also available. I will write more about this system at a later time. My references include discussions of the development of the MCM-70 computer in 1971-72, using this development system, as described by the York University Computer Museum MCM-70 collection. A nice view of a SIM-08 card is at
this link.)
Intel's first Intellec-branded
hardware system, first offered after 1972, used cards using the 4004 and later
the 8008 processor These were followed by their 4040 and 8080 products,
then the Multibus product line. Intellec products used a 100-pin bus and cards smaller than Multibus
cards with its 86-pin bus and secondary bus connector. . By the mid-1970's,
Intel was marketing their Multibus-based system and these older products fell
into disuse.
I have an Intel 4040 processor reference book from 1974", which discusses the Intellect 4/40. The 4/40 was used
without a disk operating system for development of 4004 and 4040 products. Software was loaded and saved via
front panel, punched paper tape, or by ROM; a PROM programmer was one of the peripherals available. The 4040-based "Intellec" is described (page 13-8 following) as the "Intellec 4/MOD 40 Microcomputer Development System" and is photographed as a box badged with "Intellec 4/40",
By board size and other graphics I can confirm it is not a Multibus-based system. The standard software was
the "PROM resident system monitor, the RAM resident macro assembler". No floppy products
or hardware are described. The 4004 processor is not described for this product in the 1977
Intel catalog referenced here.
A typical document of the era for more information is: "Automatic design of multiprocessor microprocessor systems"
by Hoo-min D. Doon of MIT; pages 6-14, Annual ACM IEEE Design Automation Conference, published 1977 in the "Proceedings
of the Symposium on Design Automation and Microprocessors".
A paper I've not reviewed yet is: "Intel SIM8-01: A Proto-PC ", Zbigniew Stachniak York University, Canada; from the "IEEE Annals of the History of Computing", Volume 29, Issue 1 (January 2007), pages 34-48
Most of the quotes below are from the "Intel Data Catalog 1977", and most of those
quotes are from Ch 13, "Intellec Development Systems":
(page 13-29 to 31, quoting) Title: Software - Intel Systems Implementation Supervisor (ISIS-II)
The ISIS-II operating system resides on the system diskette and supports a broad range
of user-oriented design aid software. Total file management and input editing features
greatly reduce software development time. the ISIS-II Relocating Macro Assembler, Linker,
Object Locator and Library Manager can be loaded from the diskette in seconds. All passes
of the assembler can be executeed without the need for user intervention. Object code
and listing may be directed to any output device, or stored as diskette files.
Powerful system console commands are provided in an easy-to-use English context.
Monitor mode can be entered by a special prefix to any system command or program call.
A file is a user-defined collection of information of variable length. ISIS-II also treats
each of the standard Intellec system peripherals as files through preassignment of unique
file names to each device. In this manner data can be copied from one device to another
(i.e. tape reader to tape punch) using the same command required to copy one diskette
data file to another. ISIS-II provides automatic implementation of random access files.
Each file is identified by a user-chosen name unique on its diskette. Up to 200 files
may be stored on each 1/4 million byte diskette."
The ATRIB, DELETE, and DIR commands have the additional capability of operating on several
files at once via the wildcard file-naming convention. As an example, the command
"DELETE *.OBJ" deletes all files in the diskette directory with the suffix ".obj"..
--end quotes--
Programs described in the "Intel Data Catalog 1977" include the 8080 Macro Assembler, Linker, Object locator, PL/M-80 "resident compiler", Text Editor, Library Manager. Also there's a reference to the ICE-80, an in-circuit emulator which includes hardware to plug into the 8080 processor socket of a target system.
Required hardware for ISIS-II is referenced as an "Intellec Microcomputer Development System, 32K bytes RAM memory, System console, Single Floppy Disk drive". Required hardware for ISIS-I (the only mention of this product in this manual) is an "Intellec Microcomputer Development System, 16K bytes RAM memory, System console, Single Floppy Disk drive." Media is the soft-sectored 8-inch SSSD diskette. The floppy controller hardware in the Intellec system was a two-card FDC channel board and FDC interface board, referred to collectively as the SBC 201 Diskette Controller; these are Multibus cards. A photo of the interface card shows it with a (c) 1975 copyright. (It's not clear that the
Intel non-Multibus system had a floppy controller card set: I simply don't know for sure - Herb Johnson).
The 8080-based "Intellec" is described as the "Intellec Microcomputer Development System" and is photographed as a box badged with "Intellec MDS", and contains Multibus cards. The "2K 8080 Intellec system monitor" provided means to load or save paper tape programs and files for assembly & text editing. The 8080 assembler is identified as "written in PL/M". Floppy disks, disk controllers and disk-based operations are not discussed in the text, but a diskette drive was described graphically as an "option".
PL/M-80 is described in a subsequent section (pages 13-33) as an "Intellec Resident Compiler" which "has been substantially enhanced since its introduction in 1973".
(I presume that refers to the 8008 version.) Another section describes it as a FORTRAN-based cross complier running on minicomputers and mainframes. Intel's early product development tools ran either as cross-products or as paper-tape or ROM-based native products, until both the 8080 and a floppy disk subsystem were developed.
In a 1975 article written by Kildall, "Microcomputer software design - a checklist"
(National Computer Conference 1975, published in conference proceedings), Kildall
describes "Intel's language, called PL/M, has been available since mid-1973 through
a cross compiler, while National's product, called PL/M+, will be available in mid-1975
...[and] is designed for the IMP-16 and PACE microcomputers." The article describes PL/M
as producing code for the 8008 and 8080 processor. Kildall developed the Intel PL/M product; it's not clear if he developed the National product. A number of other companies provided PL/I-like cross-compilers. Later, Digital Research provided a PL/I subset G native compiler for CP/M-86.
I have much more to say about PL/M in my Web page on the history of Gary Kildall and Digital Research..
This section describes the origins and history of ownership of Intel's Multibus line and software.
In brief, Intel developed the Multibus, an 86-pin bus with a secondary bus
connector, in the mid-1970's. In 1999 Intel sold its Multibus I rights to Radisys:
see these SEC document extracts for some business details.
However, it's not clear if Radisys bought or supported the old iRMX
or ISIS system software as well. As of about 2001, Radisys in turn sold their rights to Multibus and iRMX products and services to UST. Other companies continued to offer iRMX services or related products. As of 2007, I'm not sure who "owns" ISIS
or iRMX. I've tried to find links to all these and they are listed below.
Profimatics GmbH is apparently
a company in Germany which offers some iRMX support. Their site has some iRMX manuals
in PDF format, as of Dec 2003.
Tenasys is apparently another company which offers iRMX type operating systems. They say they were founded by former Intel iRMX developers. Check their site for details.
The subsequent owners of Intel Multibus rights and materials was InBus Engineering: as of 2005 the Inbus site said they are "the world's largest supplier of retired Intel Motherboards and systems". But by Dec 2005
US Technologies
had this Web page statement, a letter from Radisys dated about 2002:
"UST is the exclusive authorized and licensed source for Intel/RadiSys Multibus I and II printed circuit boards in the world. Only UST has the original Multibus I and II test software, test fixtures and engineering updates insuring you the highest quality OEM Multibus product. RadiSys has recently sold their entire Multibus business to UST. We are the world's #1 source for long-term support, including repair, upgrade, and refurbishment services for all Multibus products previously manufactured by Intel or RadiSys."
Check my Digital Research Web page for some discussion of PL/M and ISIS.
Hitex Ltd. is a UK company which offers software development tools. They have a long history of 8080 based tools and provide some support for use of old Intel tools. On their
Web site, I found this document which discusses the history of use of ISIS, MDS systems and so forth particularly in military applications support. The document says: "Ultimately, the death nell for all the old Intel MDS was Intel’s 1993 decision to jettison its tools arm and stop support for all the old systems." They add "Hitex was one of the leading pioneers of PC-hosted development tools for Intel microprocessors in the early 1980s. Unlike other independent tool manufacturers of the time, Hitex developed PC/MS-DOS interfaces to Intel MDSs and their operating systems. These are still available from Hitex to help in the maintenance of older projects."
Hitex's support seems to be through emulators, simulators, and similar tools on MS-DOS based systems
which can run the older products..
Check my Digital Research Web page for some discussion of PL/M and ISIS.
An odd source of iRMX manuals (as of Oct 2006) is from Stanford University's support site for SLAC. They have an online list of PDF's to support their use of an iRMX system. A PL/M 386 manual is among them.
The Classic Cmp Web site in Oct 2006 has a page by Joe Rigdon from about 2000 to 2003 which describes one Intel MDS product and lists some manuals. Unfortunately it's hard to navigate this site to see the other MDS systems he describes; search his
home page for "intel" to find other MDS sections.
The Unofficial CP/M Web site has some PL/M compiler sources in Fortran. Look around the page and site, for example the ISIS emulator at http://www.cpm.z80.de/binary.html under the "PLM compiler" as "plm80.zip".
In 2006-07, Udo Munk announced his updates to his Z80pack CP/M emulator for UNIX systems. This includes a number of collected CP/M OS sources, and also an MS-DOS version of an ISIS emulator to run the Intel PL/M native compiler. See my S-100 Web pointers page for more discussion of Udo Munk's work.
Matthiew Benoit has a page on the Intel iPDS and ISIS and PL/M, with documents and files and links.
Hitex, an embedded tools developer has a page which discusses old 8086 development tools including Intel's.
The 2006 Wikipedia entry for PL/M has some interesting information and Web links. It will change of course over time.
An old INFO-CPM thread, "Wanted: PL/M-80 compiler" from 1989 included a post from a Mark Alexander, possibly at Apple at the time. Says he wrote an ISIS emulator for MS-DOS and he offered sources. Reference was also made to an emulator by "RTCS Corp". The thread includes unhappy comments about some PL/M products at that time.
Here on my Web site we have some Intel and Multibus information, docs and boards. Also I have some Intel-related links in my Web page of S-100 and CP/M Web links. Parts of this document were moved from those pages in 2006-2007.
Contact information:
Copyright © 2007 Herb JohnsonBefore the 8080 and Multibus
ISIS operating system
ISIS-II SYSTEM COMMANDS
ATTRIB Assigns spedified attributes to a file such as write protect.
COPY creates copies of existing diskette files or transfers files from one device to another.
DELETE Removes a file from the diskette, thererby freeing space for allocation of other files.
DIR Listes name,s ize and attributes of files from a specified diskette directory
RENAME Allows diskette files to be crenamed.
FORMAT Initializes a diskette and allows creation of additional system or data diskettes.
DEBUG Loads a specified program from a diskette into memory and then transfers control
to the Intellec monitor for execution and/or debugging
SUBMIT Provides the capability to execute a series of ISIS-II commands which have
been previously written to a diskette file.
PL/M
ISIS and Multibus ownership
PL/M and ISIS Web links
New Jersey, USA
To email @ me, see see my ordering Web page.
