thumb|PDP-15 console

The PDP-15 was an 18-bit minicomputer by Digital Equipment Corporation that first shipped in February 1970. It was the fifth and last of DEC's 18-bit machines, a series that had started in December 1959 with the PDP-1. More than 400 were ordered within the first eight months.

In addition to operating systems, the PDP-15 has compilers for Fortran and ALGOL.

History

The 18-bit PDP systems preceding the PDP-15 were named PDP-1, PDP-4, PDP-7 and PDP-9. The last PDP-15 was produced in 1979.

Models

The PDP-15 models offered by DEC were:

  • PDP-15/10: a 4K-word paper-tape-based system
  • PDP-15/20: 8K, added DECtape
  • PDP-15/30: 16K word, added memory protection and a foreground/background monitor
  • PDP-15/35: Added a 524K-word fixed-head disk drive
  • PDP-15/40: 24K memory
  • PDP-15/50:

PDP-15/76

  • PDP-15/76: 15/40 plus PDP-11 frontend. The PDP-15/76 was a dual-processor system that shared memory with an attached PDP-11/05.

Software

DECsys, RSX-15, and XVM/RSX were the operating systems supplied by DEC for the PDP-15. A batch processing monitor (BOSS-15: Batch Operating Software System) was also available.

RSX-15

RSX-15 was released by DEC in 1971. The main architect for RSX-15 (later renamed XVM/RSX) was Dennis "Dan" Brevik.

Once XVM/RSX was released, DEC facilitated that "a PDP-15 can be field-upgraded to XVM" but it required "the addition of the XM15 memory processor."

Origin of the RSX-15 name

Commenting on the RSX acronym, Brevik says:

XVM/RSX

Later versions of the PDP-15 could run a real-time multi-user OS called XVM/RSX, an outgrowth of RSX-15. XVM Support for the PDP-15/76 included using an RK05 disk drive.

non-DEC

The MUMPS operating system, which was originally developed in 1966, was developed on the PDP-7 outside DEC. It is also available for the PDP-15.

Application software

DEC provided mathematical, scientific and commercial software application tools.

See also

  • Programmed Data Processor

References

  • a diary re PDP-15 & RSX-15