IBM 7090/7094 Page

Welcome to Dave Pitts' IBM 7090 web page. The above picture is the console of the IBM 7090 that I worked on in the Department of Physics at Indiana State University. Due to space considerations the data channel consoles were bolted to the top of the main console. We used the system in conjunction with a Digital PDP-8/I to operate laboratory instrumentation.

The original asm7090 was written in Fortran, by Phil Norisez and I, and ran on ISU's IBM 360/50. When we first got the 7090, government surplus (from the David Taylor Model Basin), all we had, in the way of peripherals, was the card reader and the printer. Later, we got the tape drives, 729 mod VI, and that allowed us to run IBSYS. The tape drives were donated by Columbia Records with an entire IBM 7074 system which was cannibalized for parts.

In seeing some of the retrocomputing effort on behalf of the IBM 7090 I've got some links that may be of interest:

asm7090 - Version 2.3.2: A Cross Assembler for the IBM 709/7090/7094. It is written in 'C' and runs on Linux, Windows and Unix Systems Services (OS/390). Supports both MAP and FAP modes of operation with MACROs and CTSS (cpumode CTSS). The IBSYS nucleus has been assembled with this version and run under the s709 simulator.
lnk7090 - Version 2.2.3: A Cross Linker for the IBM 7090. It is written in 'C' and runs on Linux, Windows and Unix Systems Services (OS/390). This version adds library support for building CTSS executables.
s709 - Version 2.4.1: An IBM 709/7090/7094 simulator originally written by Paul Pierce and mostly rewritten by me. It is written in 'C' and runs under Linux, Windows and Unix Systems Services (OS/390). Supports multi-channel Tape and DASD systems and updated floating point support. Also, supports an updated operator command interface. This version run all IBSYS jobs, including FORTRAN II. Lisp and CTSS are supported under this version. This version adds real tape drive support for Linux and Unix. Here's a zip file of the source.
Here is a zip file ,Version 2.3.5, containing Windows executables.
utilities - Version 1.1.14. Utilities to support the creation of system load tapes, a BCD dump utility, a simple disassembler and a GE label tape reader. Also, the utilities used by the simh simulator have been moved here for one stop shopping. This version adds several utilities to support CTSS development.
IBSYS Source - This source archive has been expanded to contain many of the subsystem sources. This includes: COBOL, FORTRAN (II & IV), MAP assembler, IBSYS nucleus, IBJOB monitor and others.
CTSS - (Compatible Time Sharing System) This is a reconstruction of the system from the listing tapes. The system supports the MAD compiler, FAP assembler, RUNOFF, RUNCOM, some editors, LISP and more.
- CTSS Source - Version 1.0.7: This source archive contains the current snapshot of the CTSS effort.
- CTSS Kit - Version 1.0.7: This archive contains prebuilt "tapes" and images to run CTSS.
- CTSS Windows Kit - Version 1.0.7: This zip archive contains prebuilt "tapes" and images to run CTSS. It also includes a prebuilt s709 and utilities.
Jack Harper's page for information about the IBM 7090 system. It describes the system architecture and has lots of photo links.

Here are some packages for other IBM 7000 architectures:

asm7070 - Version 0.2.0: A Cross Assembler for the IBM 7070/7074. It is written in 'C' and runs on Linux, Windows and Unix Systems Services (OS/390). Is a preliminary release and supports the basic machine instructions and a few of the pseudo operations.
asm7080 - Version 0.3.0: A Cross Assembler for the IBM 705/7080. It is written in 'C' and runs on Linux, Windows and Unix Systems Services (OS/390). Is a preliminary release and supports the basic machine instructions and a few of the pseudo operations. Also, basic system macros have been added.

If you have any IBM 7070 or 7080 code or have programmed on these systems; please drop me a note. I'm looking for programs to test the assemblers.

This home page is maintained by David Pitts. Please email with comments and corrections.
Last modified 2023/06/27.