The Hewlett-Packard 9830A is a desktop-sized, all-in-one computer, released in 1972. It was usable out-of-the-box, booting to BASIC (stored in ROM) immediately at power-up. It incorporates a 16-bit processor, full alpha-numeric keyboard, 32-character alpha-numeric LED display, and digital cassette tape drive, in one package, with ROM firmware and I/O expansion capabilities. Read-write memory is up to 8KW (16KB). The tape cassettes can hold on the order of 35KW (70KB) each.

The 9830 was something of a closed system, to my knowledge there was no complete service manual or schematic released by HP in 'normal' publications, nor was there machine language or assembly programming documentation or support. It was intended to be used and programmed in BASIC, and that's all.

HP did file a substantial patent (UK#1,444,141, US#4012725) however, that covers the 9830 in considerable depth, if one can stand wading through the hundreds of pages of diagrams, listings and patent-ese language with no table-of-contents or index. The UK patent is better organised than the US version, and far preferable for perusal. A version of the UK patent and a rudimentary-and-partial table of contents for the same are linked below.

These pages focus on technical aspects of the HP 9830. For some history of the development of the 9830 see the great articles at Working in conjuncton with Rob Ferguson, these pages present:


While it was too expensive in its day to be considered generally obtainable by individuals, the 9830A is nonetheless a good contender for the title of 'first personal computer'. Two other comparable machines in the marketplace in the period were the Wang 2200 (1973/76) and the IBM 5100 (1975). The 9830 predates the first generation of hobbyist/personal microcomputers (the Altair, IMSAI, SWTP-6800, etc.), and was released 5-6 years before the trinity of better-known, somewhat-equivalent, 'easy-to-use' personal computers of the Apple II, Commodore PET, and Radio Shack TRS-80.


The 9830 was not known for its speed. It was intended as a capable but economic machine. According to, the processor was slow enough that Bill Hewlett expressed some criticism of the slowness of the sibling 9820 during development (the HP 9830, 9820 and 9810 use the same processor).

Instruction execution times vary for different instructions, but to give an idea of the processor speed, the timing for a typical instruction has been calculated. It turns out the basic add-memory-to-register (ADA/B) instruction takes 13.25uS, an execution rate of 75,000 instructions per second. See the hardware architecture page for more detail.