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 The HP 9800 is a family of what were initially called programmable calculators and later desktop computers that were made by Hewlett-Packard, replacing their first HP 9100 calculator. It is also named "98 line". The 9830 and its successors wer ...

desktop computers with an integrated monitor in a smaller package including storage and printer, at half the price.

Features

The first model of the Series 80 was the HP-85, introduced in January 1980. ''

BYTE The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable uni ...

'' 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." In a typewriter-style desktop case, the HP-85 contains the CPU and keyboard, with a ROM-based operating system (like the 9800 series), 16 KB

dynamic RAM Dynamic random-access memory (dynamic RAM or DRAM) is a type of random-access semiconductor memory that stores each bit of data in a memory cell, usually consisting of a tiny capacitor and a transistor, both typically based on metal-oxid ...

, a 5-inch CRT screen (16 lines of 32 characters, or 256×192

pixels In digital imaging, a pixel (abbreviated px), pel, or picture element is the smallest addressable element in a raster image, or the smallest point in an all points addressable display device. In most digital display devices, pixels are the sm ...

), a tape drive for DC-100 cartridges ( capacity, 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 In telecommunications, RS-232 or Recommended Standard 232 is a standard originally introduced in 1960 for serial communication transmission of data. It formally defines signals connecting between a ''DTE'' ('' data terminal equipment'') suc ...

and

GPIB Glycoprotein Ib (GPIb), also known as CD42, is a component of the GPIb-V-IX complex on platelets. The GPIb-V-IX complex binds von Willebrand factor, allowing platelet adhesion and platelet plug formation at sites of vascular injury. It is def ...

. All components were designed at the Hewlett-Packard ''Personal Computer Division'' in

Corvallis, Oregon Corvallis ( ) is a city and the county seat of Benton County in central western Oregon, United States. It is the principal city of the Corvallis, Oregon Metropolitan Statistical Area, which encompasses all of Benton County. As of the 2020 United ...

, including the processor and core chipset. 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 A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, a ...

code-named Capricorn running at and had a BASIC interpreter in ROM (). 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, in particular regarding software features relevant to technical and scientific use. The standard number representation was a

floating point In computing, floating-point arithmetic (FP) is arithmetic that represents real numbers approximately, using an integer with a fixed precision, called the significand, scaled by an integer exponent of a fixed base. For example, 12.345 can ...

format with a 12-digit (decimal) mantissa and

exponent Exponentiation is a mathematical operation, written as , involving two numbers, the '' base'' and the ''exponent'' or ''power'' , and pronounced as " (raised) to the (power of) ". When is a positive integer, exponentiation corresponds to r ...

s up to ±499. The interpreter supported a full set of scientific functions (

trigonometric functions In mathematics, the trigonometric functions (also called circular functions, angle functions or goniometric functions) are real functions which relate an angle of a right-angled triangle to ratios of two side lengths. They are widely used in a ...

logarithm In mathematics, the logarithm is the inverse function to exponentiation. That means the logarithm of a number to the base is the exponent to which must be raised, to produce . For example, since , the ''logarithm base'' 10 ...

etc.) at this accuracy. The language supported two-dimensional arrays, and a ROM extension made high-level functions such as

matrix multiplication In mathematics, particularly in linear algebra, matrix multiplication is a binary operation that produces a matrix from two matrices. For matrix multiplication, the number of columns in the first matrix must be equal to the number of rows in the s ...

and

inversion Inversion or inversions may refer to: Arts * , a French gay magazine (1924/1925) * ''Inversion'' (artwork), a 2005 temporary sculpture in Houston, Texas * Inversion (music), a term with various meanings in music theory and musical set theory * ...

available. For the larger HP-86 and HP-87 series, HP also offered a plug-in

CP/M CP/M, originally standing for Control Program/Monitor and later Control Program for Microcomputers, is a mass-market operating system created in 1974 for Intel 8080/ 85-based microcomputers by Gary Kildall of Digital Research, Inc. Initi ...

processor card with a separate

Zilog Z80 The Z80 is an 8-bit microprocessor introduced by Zilog as the startup company's first product. The Z80 was conceived by Federico Faggin in late 1974 and developed by him and his 11 employees starting in early 1975. The first working samples were ...

processor.

Historical context

The late 1970s saw the development of inexpensive home computers such as the Apple and TRS-80.

Steve Wozniak Stephen Gary Wozniak (; born August 11, 1950), also known by his nickname "Woz", is an American electronics engineer, computer programmer, philanthropist, inventor, and entrepreneur, technology entrepreneur. In 1976, with business partner Steve ...

had developed the Apple computer with the idea of a computer that worked in BASIC when it was turned on, and offered HP rights to the Apple computer. He 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. Ultimately, the market for desktop computing would go to

IBM PC compatible IBM PC compatible computers are similar to the original IBM PC, XT, and AT, all from computer giant IBM, that are able to use the same software and expansion cards. Such computers were referred to as PC clones, IBM clones or IBM PC clones ...

personal computers with a floppy disk drive based operating system, and an industry standard Intel 8088 processor (the

IBM PC The IBM Personal Computer (model 5150, commonly known as the IBM PC) is the first microcomputer released in the IBM PC model line and the basis for the IBM PC compatible de facto standard. Released on August 12, 1981, it was created by a team ...

was announced shortly after the 80 series).

Hardware

Models

ROM extensions

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

Hardware extensions

Interfaces

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 In computing, firmware is a specific class of computer software that provides the low-level control for a device's specific hardware. Firmware, such as the BIOS of a personal computer, may contain basic functions of a device, and may provide h ...

Notes

External links

series80.org
*http://www.hpmuseum.org/hp85.htm *
HP Series 80 discussion and support group
*https://vintagecomputers.sdfeu.org/hp85/ *{{cite web , url=http://www.hp.com/hpinfo/abouthp/histnfacts/museum/personalsystems/0029/0029sixviews.html , title=HP-85 personal computer, 1980—six views , work=History: Virtual Museum: Personal Systems , publisher=Hewlett-Packard
HP Series 80 Configuration Guide hosted at www.computercollector.com
Page perso d'un utilisateur du HP86, périphériques, programmation, transfert de fichiers, photos. (français)

HP86 user Web page with photos, peripherals, programmation, file transfer. (English)
HP85 Vintage Computer Teardown
series 80