MicroBee
Encyclopedia
MicroBee was a series of home computers by Applied Technology
, later known as MicroBee Systems.
The original MicroBee computer was designed in Australia
by a team including Owen Hill and Matthew Starr. It was based on features available on the DG-Z80 and DG-640 S-100
cards developed by David Griffiths, TCT-PCG S-100 card developed by TCT Micro Design and MW6545 S-100 card developed by Dr John Wilmshurst. It was originally packaged as a two board unit, with the lower "main board" containing the keyboard, Zilog Z80
microprocessor, Synertek
6545
CRT
controller, of "screen" RAM
, of character ROM
(128 characters) and of Programmable Character Graphics (PCG) RAM (128 characters). Each byte in the screen RAM addressed a character in either the character ROM or PCG RAM. A second board, termed the "core board", contained the memory, and on later models also included a floppy disk controller.
magazine, in June 1982. After a successful bid for the New South Wales
Department of Education computer tender, the computer was repackaged in a two-tone beige and black case, and sold pre-built. The ROM
held the MicroWorld BASIC
interpreter written by Matthew Starr and DGOS (David Griffiths Operating System) compatible System Monitor. In addition to the there is additional ROM socket for optional programs such as WORDBEE (Word processor
) or EDASM (a Z80 Editor/Assembler that was written by Ron Harris).
Original MicroBees ran at a clock speed of , with a video dot clock of , which was sufficient to display on a modified television
or composite monitor
. The original machines were supplied with of static RAM, and stored programs on cassette
, using Kansas City standard
and 1200 Baud
encoding.
.
ROM
. They ran CP/M
2.2. The disk controller
, based on the Western Digital
WD1793 Floppy Disk Controller
chip was contained in an add-on card that connected to the core board. The machines uses 5.25" floppy disks.
Dynamic RAM disk machines with followed soon after, with a WD2793 Floppy Disk Controller
incorporated on the core board. Later disk machines used .
of 16. The extra circuitry was contained on an additional board mounted under the main board, with numerous messy connections to the main board.
or Televideo
912 terminal. The display format was monochrome and it supported communication at either 300 or 1200 baud
. An advertisement for a "special introductory offer" with an asking price of appeared in the December 1983 issue of Electronics Today International
magazine.
, of "attribute" RAM (raising the possible number of PCG characters to ), of colour RAM, and up to ( installed) of PCG RAM. PCG RAM was sufficient to allow full mapped displays with a limited colour palette. These machines were typically sold with dual-floppy drives (or a 'Winchester' disc) held in a monitor stand that connected to the main unit.
". A frequency of means "1", means "0". At , one bit lasts , at , one bit lasts .
The bit stream is stored as, , LSB
....MSB
, .
The wav2dat software converts audio data into Microbee files.
As well, numerous adventure game
s were written, mainly in BASIC
, plus educational software.
terminal program, "Simply Write" (a word processor) and "Telcom" (a serial terminal emulator program).
MicroBee Systems also designed a PC clone, called the "Matilda", or 640TC, which ran an NEC V20
chip, and emulated the MicroBee CP/M
systems in software.
An advanced next generation model code named "Gamma", based on the Motorola 68010
and two Zilog Z80
processors, was designed but never made it to the market.
Applied Technology
Applied Technology, Australia founded by Owen Hill in 1975, was a pioneer producer of home computers that ran CP/M on Zilog Z80 microprocessors. Their MicroBee computer was the first commercial personal computer manufactured in Australia....
, later known as MicroBee Systems.
The original MicroBee computer was designed in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
by a team including Owen Hill and Matthew Starr. It was based on features available on the DG-Z80 and DG-640 S-100
S-100 bus
The S-100 bus or Altair bus, IEEE696-1983 , was an early computer bus designed in 1974 as a part of the Altair 8800, generally considered today to be the first personal computer...
cards developed by David Griffiths, TCT-PCG S-100 card developed by TCT Micro Design and MW6545 S-100 card developed by Dr John Wilmshurst. It was originally packaged as a two board unit, with the lower "main board" containing the keyboard, Zilog Z80
Zilog Z80
The Zilog Z80 is an 8-bit microprocessor designed by Zilog and sold from July 1976 onwards. It was widely used both in desktop and embedded computer designs as well as for military purposes...
microprocessor, Synertek
Synertek
Synertek, Inc. was an American semiconductor manufacturer founded in 1973. The initial founding group consisted of Bob Schreiner , Dan Floyd, Zvi Grinfas, Jack Balletto, and Gunnar Wetlesen. The manufacturing technology was MOS/LSI...
6545
Motorola 6845
The Motorola 6845 is a video address generator first introduced by Motorola and used among others in the Videx VideoTerm display cards for the Apple II computers, the MDA and CGA video adapters for the IBM PC, in the Amstrad CPC and the BBC Micro. Its functionality was duplicated and extended by...
CRT
Cathode ray tube
The cathode ray tube is a vacuum tube containing an electron gun and a fluorescent screen used to view images. It has a means to accelerate and deflect the electron beam onto the fluorescent screen to create the images. The image may represent electrical waveforms , pictures , radar targets and...
controller, of "screen" RAM
Random-access memory
Random access memory is a form of computer data storage. Today, it takes the form of integrated circuits that allow stored data to be accessed in any order with a worst case performance of constant time. Strictly speaking, modern types of DRAM are therefore not random access, as data is read in...
, of character ROM
Read-only memory
Read-only memory is a class of storage medium used in computers and other electronic devices. Data stored in ROM cannot be modified, or can be modified only slowly or with difficulty, so it is mainly used to distribute firmware .In its strictest sense, ROM refers only...
(128 characters) and of Programmable Character Graphics (PCG) RAM (128 characters). Each byte in the screen RAM addressed a character in either the character ROM or PCG RAM. A second board, termed the "core board", contained the memory, and on later models also included a floppy disk controller.
Kit beginnings
The computer was conceived as a kit, with assembly instructions included in Your ComputerYour Computer (Australian magazine)
Your Computer was an Australian computer magazine published by the White House Publishing Group and printed by The Lithgo Centre, Waterloo. Starting with the very first issue in May/June 1981 at the recommended price of $2.00...
magazine, in June 1982. After a successful bid for the New South Wales
New South Wales
New South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales...
Department of Education computer tender, the computer was repackaged in a two-tone beige and black case, and sold pre-built. The ROM
Read-only memory
Read-only memory is a class of storage medium used in computers and other electronic devices. Data stored in ROM cannot be modified, or can be modified only slowly or with difficulty, so it is mainly used to distribute firmware .In its strictest sense, ROM refers only...
held the MicroWorld BASIC
BASIC
BASIC 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....
interpreter written by Matthew Starr and DGOS (David Griffiths Operating System) compatible System Monitor. In addition to the there is additional ROM socket for optional programs such as WORDBEE (Word processor
Word processor
A word processor is a computer application used for the production of any sort of printable material....
) or EDASM (a Z80 Editor/Assembler that was written by Ron Harris).
Original MicroBees ran at a clock speed of , with a video dot clock of , which was sufficient to display on a modified television
Television
Television is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound...
or composite monitor
Composite monitor
A composite monitor is any analog video display that receives input in the form of an analog composite video signal through a single cable — in contrast to multiple-cable or multiple-wire video sources such as VGA cable...
. The original machines were supplied with of static RAM, and stored programs on cassette
Compact Cassette
The Compact Cassette, often referred to as audio cassette, cassette tape, cassette, or simply tape, is a magnetic tape sound recording format. It was designed originally for dictation, but improvements in fidelity led the Compact Cassette to supplant the Stereo 8-track cartridge and reel-to-reel...
, using Kansas City standard
Kansas City standard
The Kansas City Standard , or Byte standard, is a digital data format for audio cassette drives. Byte magazine sponsored a symposium in November 1975 in Kansas City, Missouri to develop a standard for storage of digital computer data on inexpensive consumer quality cassettes, at a time when...
and 1200 Baud
Baud
In telecommunications and electronics, baud is synonymous to symbols per second or pulses per second. It is the unit of symbol rate, also known as baud rate or modulation rate; the number of distinct symbol changes made to the transmission medium per second in a digitally modulated signal or a...
encoding.
The IC model
The IC model was released in 1983, increasing the clock speed to and allowing (through use of a video clock) display of , again on a modified television or composite monitor. It also included a "Telcom" terminal emulator ROMRead-only memory
Read-only memory is a class of storage medium used in computers and other electronic devices. Data stored in ROM cannot be modified, or can be modified only slowly or with difficulty, so it is mainly used to distribute firmware .In its strictest sense, ROM refers only...
.
Disk machines
A floppy disk based machine was also released in 1983. Early disk machines used of static RAM, with a BIOSBIOS
In IBM PC compatible computers, the basic input/output system , also known as the System BIOS or ROM BIOS , is a de facto standard defining a firmware interface....
ROM
Read-only memory
Read-only memory is a class of storage medium used in computers and other electronic devices. Data stored in ROM cannot be modified, or can be modified only slowly or with difficulty, so it is mainly used to distribute firmware .In its strictest sense, ROM refers only...
. They ran CP/M
CP/M
CP/M was a mass-market operating system created for Intel 8080/85 based microcomputers by Gary Kildall of Digital Research, Inc...
2.2. The disk controller
Disk controller
The disk controller is the circuit which enables the CPU to communicate with a hard disk, floppy disk or other kind of disk drive.Early disk controllers were identified by their storage methods and data encoding. They were typically implemented on a separate controller card...
, based on the Western Digital
Western Digital
Western Digital Corporation is one of the largest computer hard disk drive manufacturers in the world. It has a long history in the electronics industry as an integrated circuit maker and a storage products company. Western Digital was founded on April 23, 1970 by Alvin B...
WD1793 Floppy Disk Controller
Floppy disk controller
A floppy disk controller is a special-purpose chip and associated disk controller circuitry that directs and controls reading from and writing to a computer's floppy disk drive . This article contains concepts common to FDCs based on the NEC µPD765 and Intel 8072A or 82072A and their descendants,...
chip was contained in an add-on card that connected to the core board. The machines uses 5.25" floppy disks.
Dynamic RAM disk machines with followed soon after, with a WD2793 Floppy Disk Controller
Floppy disk controller
A floppy disk controller is a special-purpose chip and associated disk controller circuitry that directs and controls reading from and writing to a computer's floppy disk drive . This article contains concepts common to FDCs based on the NEC µPD765 and Intel 8072A or 82072A and their descendants,...
incorporated on the core board. Later disk machines used .
Colour
A colour machine was also released in 1983, called the "32K Personal Communicator". This added a second byte of RAM for each character position, allowing each character to have 2 colours from a palettePalette (computing)
In computer graphics, a palette is either a given, finite set of colors for the management of digital images , or a small on-screen graphical element for choosing from a limited set of choices, not necessarily colors .Depending on the context In computer graphics, a palette is either a given,...
of 16. The extra circuitry was contained on an additional board mounted under the main board, with numerous messy connections to the main board.
The B-ETI Serial Terminal
The B-ETI was a Microbee based serial terminal. It could emulate either an ADM-3AADM-3A
The ADM-3A was one of the first computer terminals manufactured by Lear Siegler, first produced in 1975. It had a 12 inch screen displaying 12 or 24 lines of 80 characters.- Details :Originally priced at $1195, a DIY kit later sold for $995...
or Televideo
Televideo
TeleVideo Corporation is a U.S. company that achieved its peak of success in the early 1980s producing computer terminals. TeleVideo was founded in 1979 by K. Philip Hwang, a Utah State University graduate born in North Korea who had run a business producing CRT monitors for arcade games since 1975...
912 terminal. The display format was monochrome and it supported communication at either 300 or 1200 baud
Baud
In telecommunications and electronics, baud is synonymous to symbols per second or pulses per second. It is the unit of symbol rate, also known as baud rate or modulation rate; the number of distinct symbol changes made to the transmission medium per second in a digitally modulated signal or a...
. An advertisement for a "special introductory offer" with an asking price of appeared in the December 1983 issue of Electronics Today International
Electronics today international (magazine)
Electronics Today International or ETI was a magazine for electronics hobbyists and professionals.Originally started in Australia in 1971, ETI was published in the UK in 1972. From there, it expanded to various European countries and over to Canada....
magazine.
The Premium Series MicroBee
In 1985, a new mainboard was introduced. The resulting machine was called the "Premium Series" model. The new mainboard had of screen RAMRam
-Animals:*Ram, an uncastrated male sheep*Ram cichlid, a species of freshwater fish endemic to Colombia and Venezuela-Military:*Battering ram*Ramming, a military tactic in which one vehicle runs into another...
, of "attribute" RAM (raising the possible number of PCG characters to ), of colour RAM, and up to ( installed) of PCG RAM. PCG RAM was sufficient to allow full mapped displays with a limited colour palette. These machines were typically sold with dual-floppy drives (or a 'Winchester' disc) held in a monitor stand that connected to the main unit.
Physical coding for tape storage
MicroBee computers, at least use and conforms loosely to the "Kansas City StandardKansas City standard
The Kansas City Standard , or Byte standard, is a digital data format for audio cassette drives. Byte magazine sponsored a symposium in November 1975 in Kansas City, Missouri to develop a standard for storage of digital computer data on inexpensive consumer quality cassettes, at a time when...
". A frequency of means "1", means "0". At , one bit lasts , at , one bit lasts .
The bit stream is stored as, , LSB
Least significant bit
In computing, the least significant bit is the bit position in a binary integer giving the units value, that is, determining whether the number is even or odd. The lsb is sometimes referred to as the right-most bit, due to the convention in positional notation of writing less significant digits...
....MSB
Most significant bit
In computing, the most significant bit is the bit position in a binary number having the greatest value...
, .
The wav2dat software converts audio data into Microbee files.
Games
Many memorable games were written for the Microbee, including:- Asteroids
- Emu Joust - a JoustJoust (arcade game)Joust is an arcade game developed by Williams Electronics and released in 1982. It is a platform game that features two-dimensional graphics. The player uses a button and joystick to control a knight riding a flying ostrich...
clone - Ghost Muncher - a Pac-ManPac-Manis an arcade game developed by Namco and licensed for distribution in the United States by Midway, first released in Japan on May 22, 1980. Immensely popular from its original release to the present day, Pac-Man is considered one of the classics of the medium, virtually synonymous with video games,...
clone - Halloween Harry
- Hoards of the Deep Realm
- Kilopede - a Centipede clone
- Microspace Invaders
- Robotman - a Pac-ManPac-Manis an arcade game developed by Namco and licensed for distribution in the United States by Midway, first released in Japan on May 22, 1980. Immensely popular from its original release to the present day, Pac-Man is considered one of the classics of the medium, virtually synonymous with video games,...
clone by Paul Wilmhurst - Wumpus
- CricketCricketCricket is a bat-and-ball game played between two teams of 11 players on an oval-shaped field, at the centre of which is a rectangular 22-yard long pitch. One team bats, trying to score as many runs as possible while the other team bowls and fields, trying to dismiss the batsmen and thus limit the...
- Toady - a word guessing game
- Lemonade Stall - a game for budding business entrepreneurs.
- Underworld of Kyn - By Andy William FarrellAndy William FarrellAndy William Farrell is an Australian creative technologist and author, credited with devising the first content mark-up and tokenisation technology for ASCII terminals in 1984....
- Sword Quest - a dungeons and dragons style game by P Jepson and C Temple
As well, numerous adventure game
Adventure game
An adventure game is a video game in which the player assumes the role of protagonist in an interactive story driven by exploration and puzzle-solving instead of physical challenge. The genre's focus on story allows it to draw heavily from other narrative-based media such as literature and film,...
s were written, mainly in BASIC
BASIC
BASIC 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....
, plus educational software.
Final versions
The final version of the MicroBee, released in 1987, was the 256TC. This increased the memory to of dynamic RAM and had a new keyboard with numeric keypad. The computer had a built in disk drive supporting both (DSDD) and (SSDD) formats. Bundled software included "Videotex" a videotexVideotex
Videotex was one of the earliest implementations of an "end-user information system". From the late 1970s to mid-1980s, it was used to deliver information to a user in computer-like format, typically to be displayed on a television.In a strict definition, videotex refers to systems that provide...
terminal program, "Simply Write" (a word processor) and "Telcom" (a serial terminal emulator program).
MicroBee Systems also designed a PC clone, called the "Matilda", or 640TC, which ran an NEC V20
NEC V20
The NEC V20 was a processor made by NEC that was a reverse-engineered, pin-compatible version of the Intel 8088 with an instruction set compatible with the Intel 80186...
chip, and emulated the MicroBee CP/M
CP/M
CP/M was a mass-market operating system created for Intel 8080/85 based microcomputers by Gary Kildall of Digital Research, Inc...
systems in software.
An advanced next generation model code named "Gamma", based on the Motorola 68010
Motorola 68010
The Motorola MC68010 processor is a 16/32-bit microprocessor from Motorola, released in 1982. In line with the Motorola 68000 naming convention, it is usually just referred to as the 010 ....
and two Zilog Z80
Zilog Z80
The Zilog Z80 is an 8-bit microprocessor designed by Zilog and sold from July 1976 onwards. It was widely used both in desktop and embedded computer designs as well as for military purposes...
processors, was designed but never made it to the market.
Emulators
- freecode.com - uBee512 Microbee emulator supporting all Z80 models
- nanowasp.org - A Microbee Emulator -"Nanowasp"
- mess.org - Microbee on the MESSMESSMulti Emulator Super System is an emulator for many game consoles and computer systems, based on the MAME core.The primary purpose of MESS is to preserve decades of computer and console history...
(Multi Emulator Super System)
External links
- The Microbee Software Preservation Project (MSPP)
- The Microbee Software Preservation Project file repository (MSPP)
- The Microbee Beeboard - Discussion Forum (Since 2002)
- The Microbee Beeboard Virtual Museum
- Microbee Beeboard - File Repository (Games, ROMs, Disks, Utilities & Documentation)
- The Microbee story
- Microbee microcomputer micro-FAQ
- Australian Computer Museum Society Inc microbee page
- The PC Museum, Applied Technology page
- Matthew Geier's notes and pictures, including a working "Gamma"
- Alistair Shilton's "Archaic Electronics Labyrinth" including a page (Picomozzy - the Microbee 32k Emulator) with scans of Microbee technical reference manualsArchived version
- OLD-COMPUTERS.COM's page dedicated to the Microbee systems
- The Microbee ArchiveArchived version
- Microbee Documentation Project
- The Powerhouse Museum (Sydney Australia) - K1431 Microcomputer, "Microbee" 16KROM, early Kit computer.