Jump to content
 







Main menu
   


Navigation  



Main page
Contents
Current events
Random article
About Wikipedia
Contact us
Donate
 




Contribute  



Help
Learn to edit
Community portal
Recent changes
Upload file
 








Search  

































Create account

Log in
 









Create account
 Log in
 




Pages for logged out editors learn more  



Contributions
Talk
 



















Contents

   



(Top)
 


1 References  














CPMulator







Add links
 









Article
Talk
 

















Read
Edit
View history
 








Tools
   


Actions  



Read
Edit
View history
 




General  



What links here
Related changes
Upload file
Special pages
Permanent link
Page information
Cite this page
Get shortened URL
Download QR code
Wikidata item
 




Print/export  



Download as PDF
Printable version
 
















Appearance
   

 






From Wikipedia, the free encyclopedia
 


CPMulator
Developer(s)Keystone Software Development
Initial release1984; 40 years ago (1984)
Operating systemDOS
Platformx86
TypeEmulator
LicenseProprietary software

CPMulator is a program to emulate the CP/M operating system under x86 DOS. The program was developed in 1984 by Keystone Software Development. The company was owned and operated by Jay Sprenkle.[1]

The NEC V20 processor released that year was guaranteed to be hardware compatible with the Intel 8088. After reviewing the instruction timing of the math operations and instruction addressing hardware it was determined it could slightly speed up existing 8088 based IBM PC machines.[2] Keystone software started advertising "PC Speedup Kits" in PCWeek magazine. The CPU was socketed in IBM PC's so it could easily be replaced. In practice most programs received a 5% speed increase but those that were math intensive were much improved. One customer reported his monte carlo simulation of a nuclear reactor was so much faster that he "double checked the results because he couldn't believe it was finished."

CPMulator was developed after the release of the V20. The processor was also able to emulate the Intel 8080 instruction set in hardware.[2] This opened the possibility of running older code on the new IBM machines. CPMulator was designed to modify CP/M binaries to make them run as if native 8088 DOS programs. The code to put the CPU in emulation mode was prefixed to each CP/M executable. Any calls to the CP/M operating system were intercepted and translated to DOS operating system calls. The program would leave 8080 emulation mode, make the operating system call, translate the results to CP/M standards and returned to emulation mode and continue the original program.

The product went out of production after AT class machines became prevalent and NEC produced no V series pin for pin compatible version of 80286 processor.

References[edit]

  1. ^ Stevens, Kenneth (2008). The Emulation User's Guide. Lulu.com. pp. 62–63. ISBN 978-1-43575373-0. Retrieved 2020-01-25.
  • ^ a b Davis, Randy (December 1985 – January 1986). Written at Greenville, Texas, USA. "The New NEC Microprocessors - 8080, 8086, Or 8088?" (PDF). Micro Cornucopia. No. 27. Bend, Oregon, USA. pp. 4–7. ISSN 0747-587X. Archived from the original (PDF) on 2020-02-11. Retrieved 2020-02-11.

  • Retrieved from "https://en.wikipedia.org/w/index.php?title=CPMulator&oldid=1124640464"

    Categories: 
    CP/M
    Microcomputer software
    Hidden categories: 
    CS1 location test
    Articles needing additional references from July 2018
    All articles needing additional references
    Use dmy dates from January 2020
     



    This page was last edited on 29 November 2022, at 19:23 (UTC).

    Text is available under the Creative Commons Attribution-ShareAlike License 4.0; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.



    Privacy policy

    About Wikipedia

    Disclaimers

    Contact Wikipedia

    Code of Conduct

    Developers

    Statistics

    Cookie statement

    Mobile view



    Wikimedia Foundation
    Powered by MediaWiki