Heathkit H-11
Encyclopedia
The Heathkit H11 Computer was an early kit-format personal computer introduced in 1977. It was essentially a Digital Equipment
PDP-11
in a small form factor case, designed by Heathkit. The H11 was one of the first 16-bit
personal computer
s, at a list price of US$1,295
Initial memory limitations restricted the selection of software the system could handle, but the system could be expanded to 32KB of RAM. Many PDP-11 operating systems and programs ran without trouble. The system would also work with most DEC PDP-11 equipment, including many Q-bus compatible peripherals.
Digital Equipment Corporation
Digital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...
PDP-11
PDP-11
The PDP-11 was a series of 16-bit minicomputers sold by Digital Equipment Corporation from 1970 into the 1990s, one of a succession of products in the PDP series. The PDP-11 replaced the PDP-8 in many real-time applications, although both product lines lived in parallel for more than 10 years...
in a small form factor case, designed by Heathkit. The H11 was one of the first 16-bit
16-bit
-16-bit architecture:The HP BPC, introduced in 1975, was the world's first 16-bit microprocessor. Prominent 16-bit processors include the PDP-11, Intel 8086, Intel 80286 and the WDC 65C816. The Intel 8088 was program-compatible with the Intel 8086, and was 16-bit in that its registers were 16...
personal computer
Personal computer
A personal computer is any general-purpose computer whose size, capabilities, and original sales price make it useful for individuals, and which is intended to be operated directly by an end-user with no intervening computer operator...
s, at a list price of US$1,295
Specifications
The H11 featured:- Processor — LSI-11 (KD11-HA half-size or "double-height" card)
- Speed — 2.5 MHz
- ROM — 8KB (max)
- RAM — 32KB (max)
- Slots — 7 Q-busQ-BusThe Q-bus was one of several bus technologies used with PDP and MicroVAX computer systems manufactured by the Digital Equipment Corporation of Maynard, Massachusetts....
slots - Storage — H27 8-inch floppy drive (2 256k 8-inch single sided drives) or paper tape
- I/O — serial (RS-232RS-232In telecommunications, RS-232 is the traditional name for a series of standards for serial binary single-ended data and control signals connecting between a DTE and a DCE . It is commonly used in computer serial ports...
) or parallel ports - Operating system — HT-11 (a simplified version of RT-11RT-11RT-11 was a small, single-user real-time operating system for the Digital Equipment Corporation PDP-11 family of 16-bit computers...
) - Instruction set — PDP-11/40 instruction set which included over 400 instructions
- Languages — BASICBASICBASIC is a family of general-purpose, high-level programming languages whose design philosophy emphasizes ease of use - the name is an acronym from Beginner's All-purpose Symbolic Instruction Code....
, FocalFocalFocal may refer to:*Focal , an Irish lexicographical website*FOCAL **FOCAL-69**Focal *Focal Radio, a radio station based in Stoke-on-Trent, England-See also:*Focus...
and others
Initial memory limitations restricted the selection of software the system could handle, but the system could be expanded to 32KB of RAM. Many PDP-11 operating systems and programs ran without trouble. The system would also work with most DEC PDP-11 equipment, including many Q-bus compatible peripherals.
External links
- Heathkit H-11 Computer, Heathkit Computer Advertisements, Decode Systems
- Computer Museum illustration of fully expanded H11 with the Heath/Zenith label.