---
title: OHIO Scientific Challenger 1P
categories:
- Computers
types:
- Home Computer
origins:
- U.S.A.
years:
- '1979'
cpus:
- '6502'
params:
  name: Challenger 1P
  image: /media/museum/photos/ohioscient_challenger1p_system_1.jpg
  company: /companies/ohio-scientific
  company_name: OHIO Scientific
  specs:
  - label: NAME
    value: Challenger 1P
  - label: MANUFACTURER
    value: OHIO Scientific
  - label: TYPE
    value: Home Computer
  - label: ORIGIN
    value: U.S.A.
  - label: YEAR
    value: '1979'
  - label: BUILT IN LANGUAGE
    value: Microsoft BASIC
  - label: KEYBOARD
    value: Full stroke 53 keys
  - label: CPU
    value: '6502'
  - label: SPEED
    value: 1 MHz.
  - label: CO-PROCESSOR
    value: None
  - label: RAM
    value: 4 KB (static) expandable to 8 KB on board
  - label: VRAM
    value: 1 KB
  - label: ROM
    value: 8 KB
  - label: TEXT MODES
    value: 24 chars. x 24 lines
  - label: GRAPHIC MODES
    value: Only built-in graphic characters
  - label: COLORS
    value: Monochrome
  - label: SOUND
    value: No sound
  - label: SIZE / WEIGHT
    value: Unknown
  - label: I/O PORTS
    value: Tape recorder (input/output jacks for 300 baud Kansas City Standard tape storage), Composite video
  - label: POWER SUPPLY
    value: Built-in 5V power supply unit
  - label: PERIPHERALS
    value: 24 KB memory board, floppy discs
  - label: PRICE
    value: About $350
  tabs:
  - photos
  - links
  - docs
  forum_thread: 794
  photos:
  - title: BACK SIDE
    subtitle: ''
    text: ''
    image: /media/museum/photos/ohioscient_challenger1p_back_1.jpg
  links:
  - title: Web Wiz CAPTCHA
    url: http://www.webwizcaptcha.com
    text: ''
  docs:
  - title: SUPERBOARD II / CHALLENGER 1P - USERS MANUAL
    url: null
    cover: /media/museum/docs/couvs/challenger_user-manual.jpg
    text: |-
      **SUPERBOARD II / CHALLENGER 1P - USERS MANUAL**\
      written by Ohio Scientific

       compiled/archived by David Wilson\
       type of document : PDF\
       size : 2,7 MB\
       source : www.old-computers.com
  - title: THE 8K BASIC-IN-ROM - REFERENCE MANUAL
    url: null
    cover: /media/museum/docs/couvs/doc_ohio-scientific_osi-basic.jpg
    text: |-
      **THE 8K BASIC-IN-ROM - REFERENCE MANUAL**\
      written by Ohio Scientific

       compiled/archived by David Wilson\
       type of document : PDF\
       size : 576 KB\
       source : www.old-computers.com
  - title: CHALLENGER 1P - TECHNICAL REPORT
    url: null
    cover: /media/museum/docs/couvs/challenger-1p_technical-report.jpg
    text: |-
      **CHALLENGER 1P - TECHNICAL REPORT**\
      written by Ohio Scientific

       compiled/archived by David Wilson\
       type of document : PDF\
       size : 1,4 MB\
       source : www.old-computers.com
  - title: THE CHALLENGER CHARACTER GRAPHICS REFERENCE MANUAL
    url: null
    cover: /media/museum/docs/couvs/challenger_characters-graphics-reference-manual.jpg
    text: |-
      **THE CHALLENGER CHARACTER GRAPHICS REFERENCE MANUAL**\
      written by Ohio Scientific

       compiled/archived by David Wilson\
       type of document : PDF\
       size : 1,3 MB\
       source : www.old-computers.com
  related:
  - /museum/ohio-scientific-challenger-4p
  - /museum/ohio-scientific-challenger-ii
  - /museum/ohio-scientific-challenger-iii
  - /museum/ohio-scientific-superboard-ii
  oc_id: 813
  source:
    url: https://web.archive.org/web/20230206200042/http://www.old-computers.com/museum/computer.asp?c=813
    date: '2023-02-06'
---

Ohio Scientific, based in Ohio, USA, were the makers of the Superboard II. The Challenger 1P and Challenger **IIP-MF** were essentially cased versions of this single board system with integrated keyboard, a single 5Volt power supply and the first 6502 version of Microsoft BASIC interpreter.

An optional floppy disk controller and a extra 24K of ram for this unit was available using a 610 expansion board.

The **C1P-MF** was an upgraded version of the C1P having 20 KB of RAM and one 90 KB floppy disc drive. Memory could be upgraded up to 32 KB.

The Superboard and its derivatives had good user support and many programs were available.

---

Some additional information from **Mark Alsing**:\
It had basic keyclick sound capability that could be added by popultaing components (resitors and caps) on the main board.An RS-232 interface could also be added this way and there was a cut-out on the back to mount a DB-25 connector for it. Video output was composite and required an RF modulator to display output on a regular TV. I had a MicroVerter box that put the output on ch. 13 or 14.

**Ken Jordan**, a game developer who got his start on the OSI-C1P, reports :\
The text mode was really 32 x 32, but because of TV overscan only 24 x 24 was used.\
As was common, I soldered Atari joysticks to the numeric keys to allow gaming (there was a standard for this mod).