The HP-85's typewriter-style desktop case contained a 5" CRT screen, a tape drive (DC-100 cartridges, 210 kB capacity, 650 B/s transfer) and a thermal printer. It could be expanded through four module slots in the back that could hold memory modules, ROM extensions, or interfaces such as RS-232 and GPIB.
The machines were built around an HP-proprietary CPU running at 625 kHz (0.6 MHz, sic) and had a BASIC interpreter in ROM. Programs could be stored on DC-100 cartridge tapes or on disk/tape units connected through GPIB.
Despite the comparatively slow processor, the machines were quite advanced compared to other desktop computers of the time. The standard number format was a 12-digit (decimal) mantissa with exponents up to ±499, and the interpreter supported a full set of scientific functions at this accuracy.
They also included graphics functions (on screen and hard copy) in the standard model and could easily be expanded in hardware and software - for example, matrix operations could be added to the BASIC interpreter through option ROMs. For the larger HP-86 and HP-87 series, HP also offered a plug-in CP/M processor card.
|HP-85A||1979||$3,250||16 K RAM, 32 K ROM; 5" CRT, 32×16 text or 256×192 graphics; tape drive, printer|
|HP-83||1981||$2,250||same as HP-85 without printer and tape drive|
|HP-86A||1982||$1,795||external composite monitor, no tape drive or printer; 2 interfaces for 9130 floppy & 1 Centronics printer port built in; 64 K RAM|
|HP-87||1982||?||9" 80×16 (256×128) display, no printer, no tape, built-in HPIB; 32 K RAM|
|HP-85B||?||?||update to HP-85A; 64 K RAM (32 K program, 32 K ramdisk; I/O, EDISK, and Mass Storage ROM built in|
|HP-86B||?||?||update to HP-86; built-in HPIB instead of diskette and Centronics ports; 128 K RAM; EDISK ROM built-in|
|HP-87XM||1983(?)||$2,995||update to HP-87; built-in HPIB; 128 K RAM|
|HP-9915A/B||1980||?||industrial rack-mount version of HP-85A/B without screen or keyboard, I/O ROM and Program Development ROM built in|
Note: The HP-86/87 series used different ROMs (yellow labelling) from the 85/83 models (white labelling).
|00085-15003||00087-15003||I/O||Access GPIB, serial and parallel (GPIO) interfaces|
|00085-15001||built-in||Mass Storage||Access Amigo compatible diskette/disk drives on GPIB. Built into 85B, 86, 87.|
|00085-15002||00087-15002||Printer / Plotter (85) or Plotter (87)||Enhanced printer support including screen-dump to external dot matrix printer|
|00085-15005||00087-15005||Advanced Prog.||Extended Basic commands|
|n/a||00087-15012||Electronic Disk||Use part of RAM as a disk drive|
|00085-15004||00087-15004||Matrix||Mathematical matrix operations including inversion (solving linear equation systems)|
|00085-15007||00087-15007||Assembler||Edit and assemble Series 80 assembler source|
|n/a||00087-15011||MIKSAM||File record management|
|00085-15013||00087-15013||EMS||Access to SS-80 compatible mass storage|
|00085-60952||?||Service||Diagnostic routines for service/maintenance|
|98151A||n/a||Program Development||Support HP-9915 front panel, or to emulate it on an 83/85|
|82936A||ROM drawer for up to 6 of the above ROMs (max 1 per unit)|
|82903A||16 K Memory module, for HP-85A only (max 1 per unit)|
|82908A||64 K Memory module, for HP-85B or HP-86/87|
|82909A||128 K Memory module, for HP-85B or HP-86/87|
|82967A||Speech synthesis module|
|82900A||CP/M System (for HP-86/87 only). Contains a Zilog Z80 microprocessor and 64 kilobytes dedicated RAM.|
|82928A||System monitor for assembly development|
|82929A||Programmable ROM drawer for standard EPROMs|
|82937A||HP-IB Interface (GPIB, IEEE-488, IEC625)|
|82939A||RS-232 Serial Interface|
|82940A||GPIO Interface (general-purpose 4 × 8 bit parallel)|
|82941A||BCD Interface (parallel, 11 binary coded decimal digits + sign)|
|82949A||Printer Interface (Centronics parallel)|
|82950A||Modem (110/300 bit/s, Bell 103/113)|
|82966A||Data Link Interface (to connect to HP1000/3000 hosts)|