This is a software emulator for a minicomputer architecture sold by Prime Computer from the early 70s through about 1993. Prime's initial business plan was to make systems compatible with the Honeywell x16 family, which had then-recently been discontinued. Prime extended the architecture heavily.
Beginning in 2005, Jim Wilcoxson developed an emulator for Prime Computer's 50-Series architecture. The emulator originally ran on the PowerPC architecture. In late 2011, Jim ported it so it would run on x86. This entailed solving endianness issues (The 50-Series is big-endian), as well as re-optimizing the code for performance without the host processor having a large set of general-purpose registers.
Coming soon, we swear! There is a unix man page included in this repository.
Github discussions are now enabled for this repository, and can be used to ask for help.
There are a set of emulators available for public use. These may be
accessed via telnet to the appropriate port on em.prirun.com.
| PRIMOS Revision | Port |
|---|---|
| 18.3.1 | 8007 |
| 19.2 | 8001 |
| 20.2.8 | 8002 |
| 21.0.6 | 8003 |
| 22.1.4 | 8004 |
| 23.4.Y2K.R1 | 8005 |
| 24.0.0.r15 | 8006 |
For example, telnet em.prirun.com 8001.
Some information about the Prime company is available in the FAQ which was assembled by denizens of the comp.sys.prime usenet group and Info-Prime mailing list around the time Prime's 50-Series business unit ceased to exist. A reformatted copy is available here.
A growing collection of Prime and related documentation is available at sysovl.info. A howto on installing PRIMOS in the emulator is here. Discussion of adapting these instructions to 22.1.4 has been occurring on the cctalk mailing list.
Distribution tape sets for four versions of PRIMOS, with small sets of layered products, are available from sysovl.info:
- Rev 21.0.6, including BASIC, FTN, BRMS, INFORMATION
- Rev 23.2.0, including BASIC, FTN, MIDASPLUS, DRB, DTB, FS_RECOVER, PL1_LIBRARY
- Rev 23.4.Y2K,R1, including BASIC, FTN, MIDASPLUS, DRB, DTB, FS_RECOVER, PL1_LIBRARY
- Rev 24.0.0.r15, including BASIC, FTN, MIDASPLUS, DRB, DTB, FS_RECOVER, PL1_LIBRARY
Tapes for two versions of PRIMOS (these are not clean distribution sets) are available from Bitsavers:
- Rev 22.1.4 [has issues, written with newer magsav, can't restore itself]
- Rev 22.1.4 repacked [use this instead, resaved with Rev. 22 magsav]
- Rev 19.? [a backup from an installed system]
We'd prefer that you build your own from the source tree, but if that's not possible, a set of pre-compiled binaries is available. Included are:
- Linux i386
- Linux amd64
- Linux armhf (RasPi / BeagleBone)
- FreeBSD amd64
- Solaris amd64
A set of sample system images derived from the public emulators can
be downloaded to get you started. These tarballs preserve sparse
allocation ("holes"), so that uninitialized space in the disk images
does not occupy actual space. You may need to tell tar to preserve
this sparse allocation when you extract, e.g. with the -S option.
The current tarball is 150,029,183 bytes, and its sha256sum is f5b8008d7c53171f50ad95dd5cc537ba48ca419049518f8ea28deee009c6541a. (gzip compression would only reduce this by ~400 kilobytes.)
V5 adds the source code for PRIMOS 19.2, and the diagnostics programs, to that image.
V4 corrected ACL problems in the Rev19 and Rev24 images.
V3 removed additional junk, and rebuilt the disk images as 600
MB drives, split 30/10 heads filesystem/paging. It also included
enhancements to the wrapper scripts: directory independence and the
ability to run the runem script from a terminal.