Hitachi H8

H8 is the name of a large family of 8-bit and 16-bit microcontrollers made by Renesas Technology Corp., originating in the early 1990s within Hitachi Semiconductor and still actively evolving as of 2003.

Subfamilies include the H8/300, H8/300H, H8/500, and H8S series, each with dozens of different parts, varying by speed, selection of built in peripherals such as timers and serial ports, and amounts of ROM and RAM. Built in ROM tends to range from 16K to 128K bytes, and RAM from 512 to 4K bytes.

The basic architecture of the H8 is patterned after the DEC PDP-11, with eight 16-bit registers (the H8/300H and H8/S have an additional bank of eight registers), and a variety of addressing modes. Several companies provide compilers for the H8 family, and there is a complete GNU port, including a simulator. There are also various hardware emulators available.

H8s may be found in digital cameras, printer controllers, and in various automotive subsystems. Also, the LEGO Mindstorms advanced robot toy/educational tool uses this architecture (a H8/300, to be specific).

The SuperH is a 32-bit extension of the H8 design.