A PDP-7 in Oslo, Norway
|Manufacturer:||Digital Equipment Corporation|
|Word Size:||18 bits|
|Logic Type:||PNP Transistor FLIP CHIPs|
|Memory Speed:||1.75 μsec|
|Physical Address Size:||15 bits (32K words)|
|Virtual Address Size:||13 bits (direct), 15 bits (extended)|
The PDP-7 was the third of Digital's 18-bit machines, with essentially the same instruction set and architecture as the predecessor PDP-4 and successor PDP-9. It was the first wire-wrapped PDP. It was the first to use their Flip-Chip® technology, but also included the older System Modules.
In 1969, Ken Thompson wrote the first UNIX system in assembly language on a PDP-7, then named Unics as a somewhat treacherous pun on Multics, as the operating system for Space Travel, a game which required graphics to depict the motion of the planets. A PDP-7 was also the development system used during the development of MUMPS at MGH in Boston a few years earlier.
There are a few remaining PDP-7's still in operable condition. One under restoration in Oslo, Norway, has been thrown away.
The PDP-7 can be emulated with SIMH. DECSys and some other software is available and can run on the emulator.
- Digital Equipment Corporation PDP-7 - Extensive site with a large amount of material
- "The famous PDP-7 comes to the rescue" (Bell Labs' Unix history)
- http://research.microsoft.com/~gbell/Digital/timeline/1964-3.htm PDP-7 entry from Year 1964 in the DIGITAL Computing Timeline
- http://heim.ifi.uio.no/~toresbe/dec PDP-7 restoration project located in Oslo, Norway