The North Star Horizon was a popular

8-bit In computer architecture, 8-bit Integer (computer science), integers or other Data (computing), data units are those that are 8 bits wide (1 octet (computing), octet). Also, 8-bit central processing unit (CPU) and arithmetic logic unit (ALU) arc ...

S-100 bus The S-100 bus or Altair bus, IEEE 696-1983 ''(withdrawn)'', is an early computer bus designed in 1974 as a part of the Altair 8800. The bus was the first industry standard expansion bus for the microcomputer industry. computers, consisting of ...

computer introduced in October 1977. Like most S-100 machines of the era, it was built around the

Zilog Zilog, Inc. is an American manufacturer of microprocessors and 8-bit and 16-bit microcontrollers. It is also a supplier of application-specific embedded system-on-chip (SoC) products. Its most famous product is the Z80 series of 8-bit microp ...

Z80A The Z80 is an 8-bit microprocessor introduced by Zilog as the startup company's first product. The Z80 was conceived by Federico Faggin in late 1974 and developed by him and his 11 employees starting in early 1975. The first working samples we ...

microprocessor A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circu ...

, and typically ran the

CP/M CP/M, originally standing for Control Program/Monitor and later Control Program for Microcomputers, is a mass-market operating system created in 1974 for Intel 8080/ 85-based microcomputers by Gary Kildall of Digital Research, Inc. Initial ...

operating system. It was produced by

North Star Computers North Star Computers Inc. (later styled as NorthStar) was an American computer company based in Berkeley, California existing between June 1976 (when according to popular rumor it was formed as "Kentucky Fried Computers") and 1989. Originally a mai ...

, and it could be purchased either in kit form or pre-assembled. The introductory advertisement for the North Star Horizon computer. The price for a Z80 CPU, 16K of RAM and a single floppy drive was $1599 kit and $1899 assembled. Dual drive systems were $1999 kit and $2349 assembled. The North Star Horizon was one of the first computers to have built in

floppy drive A floppy disk or floppy diskette (casually referred to as a floppy, or a diskette) is an obsolescent type of disk storage composed of a thin and flexible disk of a magnetic storage medium in a square or nearly square plastic enclosure lined w ...

s as well as being one of the first personal computers to have a

hard disk drive A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnet ...

Specifications

The computer consists of a thick aluminium chassis separated into left and right compartments with a plywood cover which sat on the top and draped over the left and right sides. (It is one of only a handful of computers to be sold in a wooden cabinet. Later versions featured an all-metal case which met safety standards.) The rear section of the compartment on the right held a

linear power supply A power supply is an electrical device that supplies electric power to an electrical load. The main purpose of a power supply is to convert electric current from a source to the correct voltage, current, and frequency to power the load. As a res ...

, including a large transformer and power capacitors, comprising much of the bulk and weight of the system. The empty section in front of the power supply normally housed one or two

floppy disk A floppy disk or floppy diskette (casually referred to as a floppy, or a diskette) is an obsolescent type of disk storage composed of a thin and flexible disk of a magnetic storage medium in a square or nearly square plastic enclosure lined w ...

drives, placed on their side so the slots were vertical. The compartment on the left held the S-100 motherboard, rotated so the slots ran left-right. Although a few logic circuits were on the motherboard, primarily for I/O functions, both the processor and the memory resided in separate

daughterboard In computing, an expansion card (also called an expansion board, adapter card, peripheral card or accessory card) is a printed circuit board that can be inserted into an electrical connector, or expansion slot (also referred to as a bus slo ...

s. Capable of running

and NSDOS (North Star's proprietary Disk Operating System), a standard North Star system sported one or two hard-sectored 5.25 inch

floppy disk drive A floppy disk or floppy diskette (casually referred to as a floppy, or a diskette) is an obsolescent type of disk storage composed of a thin and flexible disk of a magnetic storage medium in a square or nearly square plastic enclosure lined w ...

s and a

serial interface In computing, a serial port is a serial communication interface through which information transfers in or out sequentially one bit at a time. This is in contrast to a parallel port, which communicates multiple bits simultaneously in parallel. T ...

to which one could connect a

terminal Terminal may refer to: Computing Hardware * Terminal (electronics), a device for joining electrical circuits together * Terminal (telecommunication), a device communicating over a line * Computer terminal, a set of primary input and output devic ...

to interact with it. NSDOS included

North Star BASIC North Star BASIC was a dialect of the BASIC programming language for the Intel 8080 microprocessor used on the North Star Horizon and available for purchase on other S-100 bus machines of the late 1970s.Richard Milewski,Micro Mike's baZic release ...

, a slightly non-standard dialect of

BASIC BASIC (Beginners' All-purpose Symbolic Instruction Code) is a family of general-purpose, high-level programming languages designed for ease of use. The original version was created by John G. Kemeny and Thomas E. Kurtz at Dartmouth College ...

, where some standard BASIC commands of the day had been changed, probably to avoid potential legal issues. Two examples of this were the EXAM and FILL commands, which took the place of the more common

PEEK and POKE In computing, PEEK and POKE are commands used in some high-level programming languages for accessing the contents of a specific memory cell referenced by its memory address. PEEK gets the byte located at the specified memory address. POKE sets ...

. The Horizon was superseded by the all-in-one North Star Advantage in 1982. The Horizon found a niche in University environments where its inbuilt

could be used to interface it to a variety of

control system A control system manages, commands, directs, or regulates the behavior of other devices or systems using control loops. It can range from a single home heating controller using a thermostat controlling a domestic boiler to large industrial c ...

s. North Star released a hard disk version, with an internal full height 5MB MFM drive. They also released an S-100 card with integrated memory and two serial ports which allowed up to eight users on one Horizon, each with their own CPU sharing the disk and other resources. This operated under

TurboDOS TurboDOS is a multi user CP/M like operating system for the Z80 and 8086 CPUs developed by Software 2000 Inc. It was released around 1982 for S100 bus based systems such as the NorthStar Horizon and the Commercial Systems line of the multiproc ...

, a multi user CP/M variant with some

Unix-like A Unix-like (sometimes referred to as UN*X or *nix) operating system is one that behaves in a manner similar to a Unix system, although not necessarily conforming to or being certified to any version of the Single UNIX Specification. A Unix-li ...

features.

References

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Specifications

References

External links