TOPS-10 System (Timesharing / Total Operating System-10) is a discontinued operating system from Digital Equipment Corporation (DEC) for the PDP-10 (or DECsystem-10) mainframe computer family. Launched in 1967, TOPS-10 evolved from the earlier "Monitor" software for the PDP-6 and PDP-10 computers; this was renamed to TOPS-10 in 1970.
Overview The TOPS-10 operating system was designed to be primarily a time-sharing system, and supported "time sharing, remote batch processing, multiprogrammed batch, real-time, and multiprocessor configurations."
TOPS-10 supported shared memory and allowed the development of one of the first true multiplayer computer games. The game, called DECWAR, was a text-oriented Star Trek-type game. Users at terminals typed in commands and fought each other in real time. TOPS-10 was also the home of the original Multi User Dungeon, MUD, the forerunner to today's MMORPGs.
Another groundbreaking application was called FORUM. This application was perhaps the first so-called CB Simulator that allowed users to converse with one another in what is now known as a chat room. This application showed the potential of multi-user communication and led to the development of CompuServe's chat application.
TOPS-10 featured an application programming interface (API) that used a mechanism called a UUO or Unimplemented User Operation. UUOs implemented operating system calls in a way that made them look like machine instructions. The Monitor Call API allowed developers to use these operations, for system programming on DECsystem-10s..
The TOPS-10 scheduler supported prioritized run queues, and appended a process onto a queue depending on its priority. The system also included User file and Device independence.
Commands The following list of commands are supported by TOPS-10.
ASSIGN ATTACH BACKSPACE BACKUP CCONTINUE COMPILE CONTINUE COPY CORE CPUNCH CREATE CREDIR CREF CSTART D(eposit) DAYTIME DCORE DDT DEASSIGN DEBUG DELETE DETACH DIRECTORY DISABLE DISMOUNT DSK DUMP E(xamine) EDIT ENABLE EOF EXECUTE FILCOM FILE FINISH FUDGE GET GLOB HALT HELP INITIA JCONTINUE KJOB LABEL LIST LOAD LOCATE LOGIN MAKE MERGE MIC MOUNT NETWORK NODE NSAVE NSSAVE OPSER PJOB PLEASE PLOT PRESERVE PRINT PROTECT PUNCH QUEUE QUOLST R REASSIGN REATTACH REENTER RENAME RESOURCES REWIND RUN SAVE SSAVE SCHED SEND SET SKIP START SUBMIT SYSTAT TECO TIME TPUNCH TYPE UNLOAD USESTAT VERSION WHERE ZERO
History Release history The PDP-6 Monitor software was first released in 1964. Support for the PDP-10's KA10 processor was added to the Monitor in release 2.18 in 1967. The TOPS-10 name was first used in 1970 for release 5.01. Release 6.01 (May 1974) was the first TOPS-10 to implement virtual memory (demand paging), enabling programs larger than physical memory to be run. From release 7.00 onwards, symmetrical multiprocessing was available (as opposed to the master/slave arrangement used before). The final release of TOPS-10 was 7.04 in 1988.
TOPS-10 today Hobbyists are now entitled to set up and use TOPS-10 under a Hobbyist's License.
The easiest way for the hobbyist to run TOPS-10 is to acquire a suitable emulator and an operating system image. TOPS-10 may also be generated from archived original distribution "tapes".
Paul Allen maintained several publicly accessible historic computer systems, including a DECsystem-2065 running TOPS-10.
Software Implemented programming languages The TOPS-10 assembler, MACRO-10, was bundled with the TOPS-10 distribution.
The following programming languages were implemented on TOPS-10 as layered products:
ALGOL, as ALGOL-10 v10B, a compiler used for general computing APL, as APL-SF V2, an interpreter used for mathematical modelling BASIC, as BASIC-10 v17F, an interpreter used for general computing BLISS, as BLISS-10 and BLISS-36, compilers used for systems programming COBOL, as COBOL-68 and COBOL-74, compilers used for business computing Fortran, as FORTRAN-10 v11, a compiler used for numerical computing CPL (an interactive PL/I subset)
The following programming languages were implemented on TOPS-10 as contributions from DECUS members:
FOCAL, as FOCAL-10 Forth, a threaded interpreted language IMP72 Lisp, an interpreter used for AI programming Pascal, a compiler used for computing education PILOT SAM76”SAM76 is an interactive text manipulation language” Simula, a compiler used for modeling SNOBOL, an interpreter used for string processing BCPL, a compiler implemented by Essex University
Implemented user utilities The following major user utilities were implemented on TOPS-10:
RMS (Records Management Services) IQL (Interactive Query language) DBMS-10 (CODASYL Database Management System)
Notable games implemented on TOPS-10 ADVENT DECWAR, as noted above FORUM, as noted above HAUNT, an early role-playing game Mac Hack, a chess program by Richard Greenblatt MUD
Legacy MS-DOS was heavily influenced by TOPS-10. Identical elements include three characters long file extensions, several standard extensions (e.g., EXE, TXT), the asterisk () as a wildcard, the usage of the slash () as a switch separator and more.
TOPS-20
Another DEC operating system for the PDP-10 was TOPS-20, which, despite its name, was almost entirely unrelated to TOPS-10. TOPS-20 supported TOPS-10 monitor calls thru an emulation facility which allowed most, but not all, TOPS-10 executables to run unchanged. TOPS-20 was not a direct followup to TOPS-10, and DEC support for both systems continued in parallel until the discontinuance of the PDP-10 line. TOPS-20 is a development of TENEX from BBN.
See also PDP-10 WAITS
References