Editing CP/M (section)

=== ZCPR ===

ZCPR<ref name="ZCPR"/> (the Z80 Command Processor Replacement) was introduced on 2 February 1982 as a drop-in replacement for the standard Digital Research console command processor (CCP) and was initially written by a group of computer hobbyists who called themselves "The CCP Group". They were Frank Wancho, Keith Petersen (the archivist behind [[Simtel]] at the time), Ron Fowler, Charlie Strom, Bob Mathias, and Richard Conn. Richard was, in fact, the driving force in this group (all of whom maintained contact through email).

ZCPR1 was released on a disk put out by SIG/M (Special Interest Group/Microcomputers), a part of the Amateur Computer Club of [[New Jersey]].

ZCPR2 was released on 14 February 1983. It was released as a set of ten disks from SIG/M. ZCPR2 was upgraded to 2.3, and also was released in 8080 code, permitting the use of ZCPR2 on 8080 and 8085 systems.

Conn and Frank Gaude formed Echelon Inc. to publish the next version of ZCPR as a commercial product, while still distributing it as free software.<ref name="byte198409">{{Cite magazine |last1=Markoff |first1=John |last2=Shapiro |first2=Ezra |date=September 1984 |title=Z Whiz |url=https://archive.org/details/BYTE_Vol_09-10_1984-09_Computer_Graphics/page/n397/mode/1up?view=theater |access-date=2025-04-10 |department=BYTE West Coast |magazine=BYTE |pages=396–397}}</ref> ZCPR3<ref name="ZCPR3"/> was released on 14 July 1984, as a set of nine disks from SIG/M. The code for ZCPR3 could also be compiled (with reduced features) for the 8080 and would run on systems that did not have the requisite [[Zilog Z80|Z80]] microprocessor. Features of ZCPR as of version 3 included shells, aliases, I/O redirection, flow control, named directories, search paths, custom menus, passwords, and online help. In January 1987, Richard Conn stopped developing ZCPR, and Echelon asked Jay Sage (who already had a privately enhanced ZCPR 3.1) to continue work on it. Thus, ZCPR 3.3 was developed and released. ZCPR 3.3 no longer supported the 8080 series of microprocessors, and added the most features of any upgrade in the ZCPR line. ZCPR 3.3 also included a full complement of utilities with considerably extended capabilities. While enthusiastically supported by the CP/M user base of the time, ZCPR alone was insufficient to slow the demise of CP/M.