While the first such systems were purchased from DEC, when DEC abandoned the PDP-10 architecture in favor of the VAX, CompuServe and other PDP-10 customers began purchasing plug compatible computers from Systems Concepts.

As of January 2007, CompuServe continues to operate a small number of PDP-10 architecture machines to perform some billing and routing functions.

* TOPS-10 Operating System for PDP-10 36-bit architecture ( True SMP since version 7. 01 )

The Adventure FORTRAN code took full advantage of the machine-dependent 36-bit architecture of the PDP-10.

The PDP-10 architecture has a few instructions which are sensitive ( alter or query the processor's mode ) but not privileged.

Some DEC PDP-10 machines stored their microcode in SRAM chips ( about 80 bits wide x 2 Kwords ), which was typically loaded on power-on through some other front-end CPU.

The PDP-10 was as much a success as the PDP-6 was a failure ; during its lifetime about 700 mainframe PDP-10s were sold before production ended in 1984.

The PDP-10 was widely used in university settings, and thus was the basis of many advances in computing and operating system design during the 1970s.

One of the most unusual peripherals produced for the PDP-10 was the DECtape.

Don Daglow wrote an enhanced version of the program called Ecala on a PDP-10 mainframe computer at Pomona College in 1973 before writing what was possibly the second or third computer role-playing game, Dungeon ( 1975 ) ( The first was probably " dnd ", written on and for the PLATO system in 1974, and the second may have been Moria, written in 1975 ).

The PDP-10 successor was to have been built by the Super Foonly project at the Stanford Artificial Intelligence Laboratory ( SAIL ) along with a new operating system.

The F-1 was the fastest PDP-10 ever built, with a clock rate of 90-100 ns per cycle, but only one was ever made.

The PDP-10 machine AI at MIT, which was running the ITS operating system and which was connected to the Arpanet, provided an early hacker meeting point.

Colossal Cave Adventure, created in 1975 by Will Crowther on a DEC PDP-10 computer, was the first widely used adventure game.

MIST ran until the machine that hosted it, a PDP-10, was superseded in early 1991.

The PDP-10 was a mainframe computer family manufactured by Digital Equipment Corporation ( DEC ) from the late 1960s on ; the name stands for " Programmed Data Processor model 10 ".

The original PDP-10 processor was the KA10, introduced in 1968.

The original PDP-10 operating system was simply called " Monitor ", but was later renamed TOPS-10.

Eventually the PDP-10 system itself was renamed the DECsystem-10.

Another modification made to the PDP-10 by CompuServe engineers was the replacement of the hundreds of incandescent indicator lamps on the KI10 processor cabinet with LED lamp modules.

The PDP-10 was eventually eclipsed by the VAX superminicomputer machines ( descendants of the PDP-11 ) when DEC recognized that the PDP-10 and VAX product lines were competing with each other and decided to concentrate its software development effort on the more profitable VAX.

The PDP-10 product line cancellation was announced in 1983, including cancelling the on-going Jupiter project to produce a new high-end PDP-10 processor ( despite that project being in good shape at the time of the cancellation ) and the Minnow project to produce a desktop PDP-10, which may then have been at the prototyping stage.

It was influential primarily as the prototype ( effectively ) for the later PDP-10 ; the instruction sets of the two machines are almost identical.

The first version of Zork was written in 1977 – 1979 using the MDL programming language on a DEC PDP-10 computer.

The original version was limited by the 18-bit word address of the PDP-10, and considerable effort was expended in keeping the implementation lean and simple.

* PIP10 ( a version of PIP used to copy files to from PDP-10 DECtapes )

The PDP-10 version of Interlisp became Interlisp-10 ; BBN had an internal project to build Interlisp-Jericho and there was a 1982 port to Berkeley Unix on the VAX by Stanford University, ISI and Xerox PARC, called Interlisp-VAX.

The first version of Zork was written in 1977 – 1979 in the MDL programming language on a DEC PDP-10 computer by Anderson, Marc Blank, Bruce Daniels, and Dave Lebling.

Julian Davies, in Edinburgh, implemented an extended version of POP-2, which he called POP-10 on the PDP-10 computer running TOPS-10.

A version of Baseball was distributed by the Digital Equipment DECUS file sharing network in 1972 to a handful of universities and other PDP-10 sites, but it fell far short of the popularity of Daglow's 1972 Star Trek.

Blank and a handful of friends wrote the original version of Zork on a PDP-10 while he was attending medical school at Albert Einstein College of Medicine in New York.

The free-play university version of Zork first became available on the MIT-DM PDP-10 in June 1977.

Colossal Cave was a year earlier, but on a mainframe, the PDP-10.

When the Flip Chip packaging allowed the PDP-6 to be re-implemented at a much lower cost, DEC took the opportunity to carry out a similar evolution of their 36-bit design and introduced the PDP-10 in 1968.

See the " References " section on the LISP article — the 36-bit word size of the PDP-6 and PDP-10 was influenced by the programming convenience of having 2 LISP pointers, each 18 bits, in one word.

Maclisp ran on DEC PDP-6 / 10 computers, initially only on ITS, but later under all the other PDP-10 operating systems.

Later MATHLAB was made available to users on PDP-6 and PDP-10 Systems running TOPS-10 or TENEX in universities.

The PDP-6 supported time sharing through the use of a status bit selecting between two operating modes (" Executive " and " User ", with access to I / O, etc., being restricted in the latter ), and a single relocation / protection register which allowed a user's address space to be limited to a set section of main memory ( a second relocation / protection register for shareable " high segments " was added on the PDP-10 ).

** ITS ( MIT's Incompatible Timesharing System for the DEC PDP-6 and PDP-10 )

** WAITS ( SAIL, Stanford Artificial Intelligence Laboratory, time-sharing system for DEC PDP-6 and PDP-10, later TOPS-10 )

ITS was written in assembly, and initially developed for the Digital Equipment Corporation PDP-6 computer, and later moved to the PDP-10 once it became available, where it saw the majority of its development and use.

Maclisp itself ran primarily on PDP-6 and PDP-10 computers, but also on the Multics OS and on the Lisp Machine architectures.

WAITS was a heavily-modified variant of Digital Equipment Corporation's Monitor operating system ( later renamed to, and better known as TOPS-10 ) for the PDP-6 and PDP-10 mainframe computers, used at the Stanford Artificial Intelligence Laboratory ( SAIL ) up until 1990 ; the mainframe computer it ran on also went by the name of " SAIL ".

Greenblatt was convinced by Ed Fredkin that time-sharing systems could be more beneficial, so he set out, along with Nelson, to write a new time-sharing system called ITS, or Incompatible Time-sharing System, initially for the PDP-6, and later the PDP-10.

In the 1950s-1970s the AI Group shared a computer room with a computer ( initially a PDP-6, and later a PDP-10 ) for which they built a time-sharing operating system called ITS.

Greenblatt, along with Tom Knight and Stewart Nelson, co-wrote the Incompatible Timesharing System, a highly influential timesharing operating system for the PDP-6 and PDP-10 used at MIT.

DECtape, originally called " Microtape ", was a magnetic tape data storage medium used with many Digital Equipment Corporation computers, including the PDP-6, PDP-8, LINC-8, PDP-10, PDP-11, PDP-12, and the PDP-15.

Computers with 36-bit words included the MIT Lincoln Laboratory TX-2, the IBM 701 / 704 / 709 / 7090 / 7094, the UNIVAC 1103 / 1103A / 1105 / 1100 / 2200, the General Electric GE-600 / Honeywell 6000, the Digital Equipment Corporation PDP-6 / PDP-10 ( as used in the DECsystem-10 / DECSYSTEM-20 ), and the Symbolics 3600 series.

It was used on the PDP-6 and PDP-10 under the name sixbit.

ITS ran on PDP-6 and, later, PDP-10 computers.

RADIX-50's 40-character repertoire ( 050 in octal ) can encode 6 characters plus 4 additional bits into one 36-bit word ( PDP-6, PDP-10 / DECsystem-10, DECSYSTEM-20 ); 3 characters plus 2 additional bits into one 18-bit word ( PDP-9, PDP-15 ); or 3 characters in one 16-bit word ( PDP-11, VAX ).