300px|thumb|IBM 4381

The IBM 4300 series (ECPS:VSE) features. The 4341-2 introduced the Extended Control Program Support:MVS (ECPS:MVS) option, a subset of System/370 extended facility.

On 20 October 1982, IBM announced a new entry-level 4341 model, Model Group 9 and a new top-of-the-line 4341, Model Group 12. Model Group 12 included the Dual Address Space (DAS) facility.

The 4341 was withdrawn on 11 February 1986.

IBM 4321

The IBM 4321 was announced on 18 November 1981.

Model Groups 1 and 2 were announced 15 September 1983 and withdrawn on 11 February 1986.

Model Group 3 was announced on 25 October 1984 and withdrawn on 11 February 1986.

Model Groups 11, 12, 13 and 14 were announced on 11 February 1986.

Model Groups 21, 22, 23 and 24 were announced on 19 May 1987 and withdrawn on 19 August 1992.

Operating systems

New releases of:

  • Disk Operating System/Virtual Storage Extended (DOS/VSE)

Other

  • Hughes Aircraft Company was the first IBM customer to install Endicott's
  • Molly-guard

Notes

References

Further reading

  • (NB. Describes the 4381.)
  • Request a login to Living Computers: Museum + Labs IBM 4361.