High Performance Language

HP 9800 series
Company type	Product line
Industry	Computer hardware
Predecessor	HP 9100 calculator
Founded	1971
Headquarters	Loveland, Colorado and Fort Collins, Colorado, United States
Products	Programmable calculators, desktop computers

Adapted from the English Wikipedia article High Performance Language, available under CC BY-SA 4.0Updated 8 August 2025

The HP 9800 series represents a line of programmable calculators and subsequently desktop computers created by Hewlett-Packard, serving as the successor to the HP 9100 calculator. The 9830 model and those that followed were genuine computers equipped with a robust BASIC interpreter.

Second generation

Notable models in this generation include:

HP 9810A (1971), a keystroke-programmable device featuring magnetic cards and an LED display,
HP 9820A (1972), the first HP unit to support algebraic input and incorporate a high-level language later known as high performance language (HPL),
HP 9821A, closely resembling the 9820A but utilizing a Compact Cassette tape drive managed by software, allowing file saving and loading by number,
HP 9830A (1972), the premier model equipped with a BASIC interpreter stored in read-only memory (ROM).

All systems within the 98x0 and 9821 range shared standardized I/O interfaces. Additionally, an 80-column thermal printer capable of printing at 400 lines per minute was designed to be mounted on top of the 9820 and 9830 units.

Third generation

Building on the success of the HP 9830, the subsequent generation introduced faster processing logic:

HP 9805A, the most affordable model sharing its casing with HP46 and HP81 pocket calculators. Released in 1973, it was a programmable calculator featuring interchangeable personality modules.
HP 9815A/S, HP’s third-generation advanced RPN desktop introduced in 1975. It was more compact, lighter, and cost-effective compared to its predecessor, offering a single-line display and replacing card drives with a tape drive.
HP 9825A/B, launched in 1976 and discontinued in 1983, supported HPL programming, had a single-line alphanumeric display, and offered an optional thermal printer.
HP 9831, a variant of the HP9825 that utilized BASIC instead of HPL.
HP 9835, which ran BASIC and later served as the foundation for the HP 250 business computer series. Versions A and B differed by their display types: CRT versus single-line.
HP 9845 series introduced models with monochrome displays (9845A/S), high-performance monochrome (9845B/T), and high-performance color (9845C/T). These systems featured one or two tape drives along with an optional integrated 80-column thermal printer positioned beneath the pillar-mounted screen.

With the exception of the 9805, all models in the 98x5 range employed DC200 cartridge tapes rather than cassettes. The HP 9825, 9831, 9835, and 9845 shared common I/O interfaces, whereas the HP 9815 utilized a distinct interface.

A precursor to contemporary personal computers

The HP 9800 series was developed initially by HP's Loveland Calculator Products Division and later by the Fort Collins Desktop Computer Division. Early desktop computers were often marketed as "Calculators" to ease purchasing procedures that differentiated between calculators and computers.

This series paved the way for HP’s Series 80 lineup, which included smaller BASIC-driven machines with CRT displays such as the HP 85 and HP 87, produced by HP’s Advanced Products Division located in Corvallis.

During the late 1970s through early 1980s, these desktop computers competed against contemporaries like the Tektronix 4051, IBM 5100, and Wang 2200. However, they were eventually surpassed by personal computers from manufacturers such as Apple and IBM PC.

Applications of the HP 9830

The HP 9830 was widely adopted by aerospace companies such as Boeing and educational institutions in Arlington, Virginia, and Renton, Washington. These schools employed pencil mark-sense cards paired with card readers for instructional purposes. In the early 1970s, Hewlett-Packard supplied National Real Estate Exchange, Inc. with an integrated hard disk system to facilitate pioneering software development in real estate. The U.S. Coast Guard utilized HP9825A units in prototype systems for teletype message forwarding and LORAN radionavigation coordination. Additionally, the HP9825 gained favor for scoring remote one-design yachting regattas—including the 1976 World Fireball and Windsurfing championships—due to its portability and as a reliable alternative to inconsistent telephone-based time-sharing computer access.

Overview of the HP 9830

The architecture of the HP 9830's processor closely mirrored that of the HP 1000/2100 series minicomputers, featuring 16-bit memory addressing alongside AX and BX general-purpose processor registers. Its performance was on par with early IBM personal computers, capable of rendering advanced three-dimensional mathematical functions such as SIN(X)/X without hidden line removal—an impressive technical accomplishment at the time.

Programs executed directly from ROM, employing a specialized call subroutine instruction modified to enable recursion through a dedicated stack register for return addresses—a forward-thinking design choice. Certain variants (for example, the 9835B) were equipped with a single-line, 32-character uppercase LED display that acted as a window into a full-screen editor featuring cursor positioning and line navigation controls—early predecessors to later screen-based editors.

Upon power-up, the system was instantly ready for computation, allowing users to enter commands like PRINT 2 + 3 and receive immediate output without complex authentication or operator intervention. Data storage relied on a computer-controlled cassette drive utilizing audio cassettes with optical end-of-tape detection; file retrieval was performed by file number, with optional support for hard disk drives.

Its companion line thermal printer produced rapid output by printing entire horizontal lines simultaneously—a speed advantage over subsequent dot matrix printers and comparable to early inkjet devices. HP incorporated thermal printing technology into many later plotting devices and terminal products.

Programming

Although built on minicomputer processor technology, the HP 9830 featured entirely redesigned system software with both its operating system and programming language embedded in ROM. Its BASIC dialect resembled the FORTRAN language used on the HP 1000 minicomputer but was simpler and interpreted rather than compiled. Interactive editing capabilities included arrow cursor keys for line scrolling and character modification—capabilities rare before screen editors became common in the late 1970s. Programmers could execute code step-by-step and examine variable states.

Early implementations of user-programmable function keys with paper labels appeared on this system, representing some of the first general function keys. These innovations influenced later screen labeled function keys found in HP and IBM machines and have since become standard features in calculators, banking terminals, and fuel dispensers.

The BASIC environment could be enhanced through ROM cartridges that added functionality such as graphics plotting, matrix operations, and string manipulation—conceptually similar to video game console cartridges. The Plotter ROM enabled straightforward chart creation using either user-defined or world coordinate systems instead of raw plotter units. These commands laid the groundwork for HP's device-independent AGL graphics language standard employed in other HP platforms like the HP 1000 minicomputer and the HP 2647 intelligent graphics terminal. <syntaxhighlight lang="basic">

10 REMARK DRAW A PARABOLA
20 SCALE -1.0, 1.0, -1.0, 1.0
30 FOR X = -1.0 TO 1.0 STEP 0.10
40 PLOT X, X*X
50 NEXT X
60 END

</syntaxhighlight> Moreover, a bootable development environment based on UCSD Pascal was offered for programming within the HP 9800 series platforms.

Overview of the HPL Language

Instead of utilizing variables such as A1 or J2, HPL employed numbered registers ranging from r1 up to r199999.

Below is an example of an HPL program designed for the HP 9825 that produces prime numbers:

0: fxd 0  
1: prt 2  
2: 1→P  
3: for C=2 to 1000000  
4: P+2→P  
5: for N=3 to P/3  
6: if int(P/N)*N = P; gto 3  
7: next N  
8: prt P  
9: next C

A notable characteristic was the use of the right arrow symbol (→), referred to as the gazinta ("goes into"), exemplified by "1→P," which is read aloud as "One gazinta P."

Other BASIC-Based Systems from HP

The Data Terminals Division at HP created the HP 2647a, a terminal programmable in BASIC that incorporated AGL—HP's proprietary standard for controlling HP 9830 plotters. The BASIC interpreter on the HP 2647 was essentially Microsoft BASIC augmented with HP-specific plotting commands, representing one of Microsoft's earliest significant collaborations with a major computer manufacturer.

HP also introduced handheld devices like the HP-75 pocket computer, which achieved limited commercial traction. The HP 9835 acted as a foundational platform for business-oriented systems and was subsequently developed into the HP 250 series.

In 1979, HP launched the Series 80 lineup, starting with the Model 85—a cost-effective personal scientific computer equipped with a robust BASIC interpreter tailored for professionals working individually.

This product line eventually transitioned into UNIX-based HP 9000 workstations after HP acquired Apollo Computer. The evolution of HP BASIC culminated in Rocky Mountain BASIC, which continued to support legacy industrial applications on these advanced workstations.

External links

HP9830 at HP Calculator Museum
hp9825.com – Second-Generation HP Desktop Calculators
hp9831.com – HP 9831 BASIC computer like HP 9825
hp9825.com – Industrial design by Leroy Lacelle
HP9845 Preservation Project at hp9845.net
HP Journal articles on programmable calculators and processors
US Patent US4075679A – Programmable calculator
Technical Desktops at HP Computer Museum
HP 9825 Scientific Desktop Computer at curiousmarc.com