PDP-10
A series of large, 36-bit mainframe-like systems built by DEC; they were basically a re-implementation of the earlier PDP-6 architecture, whose engineering had been a failure. (The machines were so similar at the programming level that PDP-6 code could run on a PDP-10.)
DEC sold 4 different generations of PDP-10 processors: the KA10, the KI10, the KL10, and the KS10. The first three were marketed as the DECsystem-10, running the TOPS-10 operating system; the third was also sold as the DECSYSTEM-20, running TOPS-20. (The varying capitalization was the result of a trademark infringment suit.)
Two other very important operating systems also ran on PDP-10's: MIT's ITS (a very advanced system, from whence came EMACS, and much more besides), and TENEX, which DEC later turned into TOPS-20.
PDP-10s were very important machines on the early Internet, being one of the few (relatively!) cheaply available machines which could run a full NCP and later TCP/IP stack as a multi-user environment at the time.
They still have a large following today. There are several goodsimulators available, notably SIMH and KLH10.
Commercial clones
- Xerox PARC: MAXC
- Foonly: F-1, F2, F3, F4, F5 (unfinished)
- Systems Concepts: SC-30M, SC-40
- CompuServe: JRG-1 (unfinished)
- XKL: TOAD-1, TOAD-2
Hobbyist recreations
- David Conroy: PDP-10/X
- Neil Franklin: (unfinished)
- Rob Doyle: KS10 FPGA
- Angelo Papenhoff: FPDPGA-6