HP-75
| Industry | Computer hardware |
|---|---|
| Founded | January 1, 1939 |
| Products | HP-75C, HP-75D portable computers |
The HP-75C and HP-75D were portable computing devices programmable in BASIC, manufactured by Hewlett-Packard between 1982 and 1986.
Equipped with a single-line liquid crystal display, the HP-75 offered 48 KiB of system ROM and 16 KiB of RAM. It featured a spacious keyboard lacking a numeric keypad, a manual magnetic card reader capable of storing 2×650 bytes per card, four memory expansion ports (one for RAM and three for ROM modules), and an HP-IL interface to connect peripherals such as printers, storage units, and testing instruments. The BASIC interpreter functioned as a basic operating system, facilitating file management for saving programs on RAM, magnetic cards, or external media like cassettes and diskettes through the HP-IL connection.
Designed with business users in mind, it included tools such as a text editor and an appointment calendar with alarm notifications, offering functionalities similar to those found in early personal digital assistants.
The HP-75D model, produced from 1984 to 1986, introduced a barcode wand interface port to support inventory management tasks more effectively.
With a manufacturer's suggested retail price of $995 for the 75C and $1,095 for the 75D, the HP-75 series was relatively costly, which impacted its widespread adoption when compared to the less expensive successor, the HP-71B.
Internally, the HP-75C’s printed circuit board carried the codename KANGAROO, while the HP-75D’s was known as MERLIN.
Reception
The magazine BYTE praised the device’s appointment scheduler for its adaptability and highlighted its capability for real-time control through BASIC programming. The publication characterized the HP-75 as "a well-integrated and powerful machine," ideal for users requiring a portable computer with sophisticated scheduling features.
External links
- HP-75 at the MoHPC
- HP Journal, June 1983 Article covering HP-75C design, IL interface, and card reader
- Internal views at MyCalcDB (displaying Kangaroo on PCB)