Editing TSX-Plus (section)

==Overview==
The system is highly configurable and tunable.{{Fact|date=February 2007}}

Due to the constraints of the memory management system in the PDP-11/LSI-11, the entire operating system core must occupy no more than 40 [[kibibyte]]s of memory, out of a maximum possible 4 [[mebibyte]]s of [[primary storage|physical memory]] that can actually be installed in those machines (mandated by the 22-bit [[address space]]). The strength of TSX-Plus is to simultaneously provide to multiple users the services of DEC's single-user [[RT-11]].<ref>{{cite magazine
   |magazine=Hardcopy  |title=The RT-11 Perspective
   |date=January 1985  |page=125 |author=Milton Campbell}}</ref> Depending on which PDP-11 model and the amount of memory, the system could support a minimum of 12 users<ref name=TSX32.DCLdialog>{{cite news
|newspaper=[[Computerworld]] |title=S&H TSX-Plus on 11/23, 11/34
|quote= efficient, general-purpose timesharing for up to 20 users on 11/23 and 11/34 based ...
|date=December 1, 1980  |page=67}}</ref> (14-18 users on a 2Mb 11/73, depending on workload). A productivity feature called "''virtual lines''" "allows a single user to control several tasks from a single terminal."<ref>{{cite magazine |magazine=Hardcopy |date=October 1982 |page=9 |title=TSX-Plus: Time Share RT-11}}</ref>

The software included a WP package named Lex-11<ref>See Tom Barnard and Ace Microsystems, Australia. New Scientist, 5 May 1983, Vol 98, No 1356, in Google Books.</ref> and a spreadsheet from [[Saturn Software]]. The machine slowed considerably if more than 8 students wanted to use the word-processing package at the same time. There was also a decision-table language called "D" from the NCC in Manchester which worked very well on TSX Plus.