HP_series_80

HP Series 80

HP Series 80

1980 Hewlett-Packard small scientific desktop computer

The Hewlett-Packard Series 80 of small scientific desktop computers was introduced in 1980, beginning with the popular HP-85 targeted at engineering and control applications. They provided the capability of the HP 9800 series desktop computers with an integrated monitor in a smaller package including storage and printer, at half the price.

A running HP-85 with a BASIC listing on its screen
HP-85B

Features

HP-86B with 9121 dual diskette drive

The first model of the Series 80 was the HP-85, introduced in January 1980.[1] BYTE wrote "we were impressed with the performance ... the graphics alone make this an attractive, albeit not inexpensive, alternate to existing small systems on the market ... it is our guess that many personal computer experimenters and hackers will want this machine."[2]

In a typewriter-style desktop case, the US$3,250 (equivalent to $12,000 in 2023) HP-85 contains the CPU and keyboard, with a ROM-based operating system (like the 9800 series), 16 KB dynamic RAM, a 5-inch CRT screen (16 lines of 32 characters, or 256×192 pixels), a tape drive for DC-100 cartridges (210 KB capacity, 650 B/s transfer), and a thermal printer. Both the screen and printer display graphics in addition to text, and the printer can copy anything shown on the screen. The chassis includes four module slots in the back for expansion which can hold memory modules, ROM extensions, or interfaces such as RS-232 and GPIB.[2] All components were designed at the Hewlett-Packard Personal Computer Division in Corvallis, Oregon, including the processor and core chipset.[1]

Later models offered variations such as different or external displays, built-in interfaces or a rack-mountable enclosure (see table below for details).

The machines were built around an HP-proprietary CPU code-named Capricorn running at 625 kHz (0.625 MHz) and had a BASIC interpreter in ROM (32 KB).[3] Programs could be stored on DC-100 cartridge tapes or on external disk/tape units.

Despite the comparatively low processor clock frequency, the machines were quite advanced compared to other desktop computers of the time,[4] in particular regarding software features relevant to technical and scientific use. The standard number representation was a floating point format with a 12-digit (decimal) mantissa and exponents up to ±499. The interpreter supported a full set of scientific functions (trigonometric functions, logarithm etc.) at this accuracy. The language supported two-dimensional arrays, and a ROM extension made high-level functions such as matrix multiplication and inversion available.

For the larger HP-86 and HP-87 series, HP also offered a plug-in CP/M processor card with a separate Zilog Z80 processor.

Historical context

The late 1970s saw the development of inexpensive home computers such as the Apple II and TRS-80. Steve Wozniak, while working at HP, had developed the Apple computer in his spare time, with the idea of a computer that worked in BASIC when it was turned on. He offered HP rights to the Apple computer, but was turned down and was given a legal release. In an interview he did note that soon after that, the calculator division was starting an 8-bit computer project called Capricorn, and he wasn't allowed to work on that project.[5] Ultimately, the market for desktop computing would go to IBM PC compatible personal computers with a floppy disk drive based operating system, and an industry standard Intel 8088 processor (the IBM PC was announced shortly after the 80 series).

Hardware

Models

More information Model, Year ...

ROM extensions

82936A drawer with three ROM modules

Note: The HP-86/87 series used different ROMs (yellow labelling) from the 85/83 models (white labelling).

More information 83/85, 86/87 ...

Hardware extensions

Rear of an HP-85B showing the four extension slots
82936AROM drawer for up to six of the above ROMs (max one per unit)
82903A16 K memory module, for HP-85A only (max one per unit) Note: *Do not use with HP-85B, may cause damage*
82908A64 K memory module, for HP-85B or HP-86/87
82909A128 K memory module, for HP-85B or HP-86/87
82900ACP/M System (for HP-86/87 only). Contains a Zilog Z80 microprocessor and 64 kilobytes dedicated RAM.
82928ASystem monitor for assembly development. Sets break-points for debugging.
82929AProgrammable ROM drawer for standard EPROMs

Interfaces

82940A GPIO Interface, enclosure removed

The interface modules for the Series 80 were built around a proprietary bus interface chip connecting a standard Intel 8049 microcontroller to the main bus. Interface functions such as handshaking were offloaded to the 8049 firmware.[15]

82937AHP-IB Interface (GPIB, IEEE-488, IEC625)
82938AHP-IL Interface
82939ARS-232 Serial interface
82940AGPIO interface (general-purpose 4 × 8-bit parallel)
82941ABCD interface (parallel, 11 binary coded decimal digits + sign)
82949APrinter interface (Centronics parallel interface)
82950AModem (110/300 bit/s, Bell 103/113)
82966AData Link Interface (to connect to HP1000/3000 hosts)
82967ASpeech synthesis module, 1500-word vocabulary using a Texas Instruments TMS5220 synthesizer chip[16]

Notes

  1. [1]
    Lynch, Todd R. (July 1980). "A New World of Personal/Professional Computation" (PDF). Hewlett-Packard Journal. 31 (7): 3–7.
  2. [2]
    Morgan, Christopher P (March 1980). "Hewlett-Packard's New Personal Computer". BYTE. p. 60. Retrieved 18 October 2013.
  3. [3]
    Lynch, Todd R. (August 1980). "A Custom LSI Approach to a Personal Compute" (PDF). Hewlett-Packard Journal. 31 (8): 16–22.
  4. [4]
    e.g. Apple II (1977), Tandy TRS-80 (1977), CBM 2001 (1977), Zenith Z89 (1980)
  5. [5]
    Byte Interview with Steve Wozniak
  6. [6]
    US$3,250 (equivalent to $12,000 in 2023) (see Inflation Conversion Factors for Dollars Archived 2007-12-30 at the Wayback Machine)
  7. [7]
    US$2,250 (equivalent to $7,500 in 2023) (ibid.)
  8. [8]
    US$1,795 (equivalent to $5,700 in 2023) (ibid.)
  9. [9]
    "Series 80 Personal Computer Price List, July 1, 1983". Retrieved 2010-02-12.
  10. [10]
    "Series 80 Personal Computer Price List, July 1, 1983". Retrieved 2010-02-12.
  11. [11]
    US$2,995 (equivalent to $9,200 in 2023) (ibid.)
  12. [12]
    "HP 9915A Pricing Information, December 1980". Retrieved 2010-02-12.
  13. [13]
    "ID" refers to the internal ROM identification, i.e. the base address, which needs to be unique in the system.
  14. [14]
    "SYSEXT-ROM-Manual (german)" (PDF). Retrieved 2016-04-27.
  15. [15]
    Nairn, John H.; Mikkelsen, Tim I.; Sweetser, David J. (July 1980). "Adding I/O Capability to the HP-85" (PDF). Hewlett-Packard Journal. 31 (7): 7–13.
  16. [16]
    "HP Computer Museum: 82967A". Retrieved 2010-02-12.
Wikimedia Commons has media related to HP series 80.
Share this article:

This article uses material from the Wikipedia article HP_series_80, and is written by contributors. Text is available under a CC BY-SA 4.0 International License; additional terms may apply. Images, videos and audio are available under their respective licenses.