| PDP-15 | |
| Developer: | Digital Equipment Corporation |
| Family: | Programmed Data Processor |
| Type: | Minicomputer |
| Lifespan: | 1979 |
| Unitssold: | More than 400 |
| Os: | DECsys, RSX-15, XVM/RSX, MUMPS, DOS-15[1] |
| Platform: | DEC 18-bit |
| Predecessor: | PDP-9 |
The PDP-15 was the fifth and last of the 18-bit minicomputers produced by Digital Equipment Corporation. The PDP-1 was first delivered in December 1959[2] and the first PDP-15 was delivered in February 1970.[3] More than 400 of these successors to the PDP-9 (and 9/L) were ordered within the first eight months.[2]
In addition to operating systems, the PDP-15 has compilers for Fortran[4] and ALGOL.[5]
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.
The PDP-15 was DEC's only 18-bit machine constructed from TTL integrated circuits rather than discrete transistors, and, like every DEC 18-bit system could be equipped with:
The PDP-15 models offered by DEC were:[7] [8] [9] [10]
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.[5]
The first DEC-supplied mass-storage operating system available for the PDP-15 was DECsys, an interactive single-user system. This software was provided on a DECtape reel, of which copies were made for each user. This copied DECtape was then added to by the user, and thus was storagefor personal programs and data. A second DECtape was used as a scratch tape by the assembler and the Fortran compiler.[13]
RSX-15 was released by DEC in 1971.[14] The main architect for RSX-15 (later renamed XVM/RSX) was Dennis "Dan" Brevik.[15] [16]
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."
The RSX-11 operating system began as a port of RSX-15 to the PDP-11, although it later diverged significantly in terms of design and functionality.[17]
Commenting on the RSX acronym, Brevik says:[18]
Later versions of the PDP-15 could run a real-time multi-user OS called XVM/RSX, an outgrowth of RSX-15.[19] [5] The XVM upgrade to RSX was multi-user, and enabled up to six concurrent teletype-based users.[20] XVM Support for the PDP-15/76 included using an RK05 disk drive.[21]
The MUMPS operating system, which was originally developed in 1966,[22] was developed on the PDP-7 outside DEC. It is also available for the PDP-15.
DEC provided mathematical, scientific and commercial software application tools.[6] [23]