Research Machines 380Z
Encyclopedia
The Research Machines 380Z (often called the RML 380Z or RM 380Z) was an early 8-bit
microcomputer
produced by Research Machines Limited in Oxford
, England
, from 1978 to 1985.
The 380Z used a Z80
microprocessor
(hence the name) with up to 56 KB
of user RAM
. When fitted with an optional floppy disk
drive the system ran the CP/M
operating system
. The basic system came with a text-only monochrome video card
, which could be enhanced with a high-resolution
graphics board.
The 380Z was sold mainly to schools in the UK, with some also sold to industry. In 1979 a dual 8-inch disk system with 56 KB of memory cost £3266
, and a 16 KB cassette-based system cost £965 (excluding VAT
).
-mount, rectangular metal case containing the power supply, a number of printed circuit board
s and the optional 5¼-inch floppy disk
drives. The front panel had a pair of strong carrying handles, a keyswitch and a reset button. The keyswitch controlled power and also enabled the reset button. The keyboard
was separate and came in a tough metal case.
Early versions were contained in a light blue metal case with a white front and had only a cassette interface or 8-inch floppy
drives; only a small number of these were made. An optional 8-bit ASCII
paper tape
punch/reader was also used, as this was a common storage medium at the time - where previous use of a computer had been limited to a teletype machine connected to mainframe
by telephone.
The system used a passive bus architecture with no motherboard – all electronics were contained on a number of cards interconnected by ribbon cable
. The only microprocessor offered was a 4 MHz
Z80A
.
, each of either 4 KB
(4 × 1024 byte
s) or 16 KB, although not every permutation was permitted. Typical configurations were 16 KB for cassette-based systems and 32, 48 or 64 KB of memory on disk-based systems. Main memory was not used by the text or graphics video cards, although memory on the video cards was bank switched
into a dedicated 1.5 KB address block.
The 380Z was also fitted with up to 5.25 KB of firmware
, known as COS. On systems fitted with less than 64 KB or RAM the COS reserved 1 KB of system RAM, leaving the rest available to the user. On the 64 KB RAM system a total of 56 KB was available to the user, with the remainder used by COS or inaccessible because of the firmware ROM
, video card, and memory-mapped I/O
.
providing a 40×24 text-only
monochrome display. Composite video
output was provided for an external monitor, and an internal RF modulator
provided a separate output to drive a television set. Later systems were supplied with an enhanced video card that was software-switchable between 40×24 and 80×24 character modes and supported a number of character attributes (underline, dim, reverse-video). Both card types were fitted with their own dedicated video memory.
In addition to the text-mode video card the system could be enhanced with a high-resolution
graphics (HRG) board. The board was fitted with a dedicated bank of 16 KB of video memory and supported two graphics modes:
A programmable lookup table
with an 8-bit output mapped the pixel value to one of 256 different colours (analogue RGB output) or intensities (composite video).
Output from the graphics board was mixed with output from the text-only video card, allowing text and graphics to be easily overlaid. The graphics output only covered the top 20 lines of the text display and therefore text output could be set to only use the bottom 4 lines if overlap was not desired.
was either via cassette tape or floppy disk
(which required a disk controller
card). The cassette interface operated at either 300 bit/s (CUTS
standard) or 1200 bit/s. COS 4.0 and later systems were not fitted with the cassette interface.
Early systems could be fitted with an optional single density
floppy disk controller
card that could interfaced to either internal 5¼-inch or external 8-inch floppy disk drives. Disk capacity was 80 KB per side on 5¼-inch disks and 250.25 KB per side on 8-inch disks. Double-sided disk drives were treated as two independent disks with a drive letter
per side. CP/M used the first 4 tracks on 5¼-inch disks and the first 3 tracks on 8-inch disks, reducing the usable capacity of a single density, single-sided 5¼-inch disk to 72 KB.
Later systems (referred to as the 380Z-D) were fitted with a double density
Intelligent Disc Controller (IDC), which increased disk capacity to either 180 KB (48 TPI
drives) or 360 KB (96 TPI drives) per side on 5¼-inch disks and 500.5 KB per side on 8-inch disks. Support for a "Winchester" hard disk drive could be provided using an intelligent Host Interface Board (HIB) that implemented a SASI interface. Hard disk systems were mainly used as file server
s for networked LINK 480Z
systems.
Other cards were optional, and included:
, from cassette or to boot
the disk operating system. COS also provided a software front panel
allowing the display of registers and memory, and supporting breakpoint
s and single-stepping of machine code.
The COS monitor was stored in either 4 KB (COS 3.4 and earlier) or 6 KB (COS 4.0 and later) of ROM, although in the latter case only 5.25 KB was mapped into addressable memory.
. COS functions were called by means of the Emulator Trap
(EMT) pseudo-opcode
, which used the Z80 RST 30H instruction to call
the EMT handler function. The EMT handler read the first byte following the RST 30H instruction to determine which EMT function was being requested; all parameters were passed in registers. A call-relative pseudo-opcode was also implemented using RST 28H.
was CP/M
, initially CP/M 1.4 and later CP/M 2.2. MP/M
II was used on the file server version, which supported a network of LINK 480Z computers using CP/NET.
. Research Machines also produced their own assembler
(ZASM), text editor
(TXED) and BASIC interpreter
.
8-bit
The first widely adopted 8-bit microprocessor was the Intel 8080, being used in many hobbyist computers of the late 1970s and early 1980s, often running the CP/M operating system. The Zilog Z80 and the Motorola 6800 were also used in similar computers...
microcomputer
Microcomputer
A microcomputer is a computer with a microprocessor as its central processing unit. They are physically small compared to mainframe and minicomputers...
produced by Research Machines Limited in Oxford
Oxford
The city of Oxford is the county town of Oxfordshire, England. The city, made prominent by its medieval university, has a population of just under 165,000, with 153,900 living within the district boundary. It lies about 50 miles north-west of London. The rivers Cherwell and Thames run through...
, England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
, from 1978 to 1985.
The 380Z used a 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
Microprocessor
A microprocessor incorporates the functions of a computer's central processing unit on a single integrated circuit, or at most a few integrated circuits. It is a multipurpose, programmable device that accepts digital data as input, processes it according to instructions stored in its memory, and...
(hence the name) with up to 56 KB
Kilobyte
The kilobyte is a multiple of the unit byte for digital information. Although the prefix kilo- means 1000, the term kilobyte and symbol KB have historically been used to refer to either 1024 bytes or 1000 bytes, dependent upon context, in the fields of computer science and information...
of user RAM
Ram
-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...
. When fitted with an optional floppy disk
Floppy disk
A floppy disk is a disk storage medium composed of a disk of thin and flexible magnetic storage medium, sealed in a rectangular plastic carrier lined with fabric that removes dust particles...
drive the system ran the 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...
operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
. The basic system came with a text-only monochrome video card
Video card
A video card, Graphics Card, or Graphics adapter is an expansion card which generates output images to a display. Most video cards offer various functions such as accelerated rendering of 3D scenes and 2D graphics, MPEG-2/MPEG-4 decoding, TV output, or the ability to connect multiple monitors...
, which could be enhanced with a high-resolution
Image resolution
Image resolution is an umbrella term that describes the detail an image holds. The term applies to raster digital images, film images, and other types of images. Higher resolution means more image detail....
graphics board.
The 380Z was sold mainly to schools in the UK, with some also sold to industry. In 1979 a dual 8-inch disk system with 56 KB of memory cost £3266
Pound sterling
The pound sterling , commonly called the pound, is the official currency of the United Kingdom, its Crown Dependencies and the British Overseas Territories of South Georgia and the South Sandwich Islands, British Antarctic Territory and Tristan da Cunha. It is subdivided into 100 pence...
, and a 16 KB cassette-based system cost £965 (excluding VAT
Value added tax
A value added tax or value-added tax is a form of consumption tax. From the perspective of the buyer, it is a tax on the purchase price. From that of the seller, it is a tax only on the "value added" to a product, material or service, from an accounting point of view, by this stage of its...
).
Architecture
The 380Z was packaged in a large, black, 19-inch rack19-inch rack
A 19-inch rack is a standardized frame or enclosure for mounting multiple equipment modules. Each module has a front panel that is wide, including edges or ears that protrude on each side which allow the module to be fastened to the rack frame with screws.-Overview and history:Equipment designed...
-mount, rectangular metal case containing the power supply, a number of printed circuit board
Printed circuit board
A printed circuit board, or PCB, is used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non-conductive substrate. It is also referred to as printed wiring board or etched wiring...
s and the optional 5¼-inch floppy disk
Floppy disk
A floppy disk is a disk storage medium composed of a disk of thin and flexible magnetic storage medium, sealed in a rectangular plastic carrier lined with fabric that removes dust particles...
drives. The front panel had a pair of strong carrying handles, a keyswitch and a reset button. The keyswitch controlled power and also enabled the reset button. The keyboard
Computer keyboard
In computing, a keyboard is a typewriter-style keyboard, which uses an arrangement of buttons or keys, to act as mechanical levers or electronic switches...
was separate and came in a tough metal case.
Early versions were contained in a light blue metal case with a white front and had only a cassette interface or 8-inch floppy
Floppy disk
A floppy disk is a disk storage medium composed of a disk of thin and flexible magnetic storage medium, sealed in a rectangular plastic carrier lined with fabric that removes dust particles...
drives; only a small number of these were made. An optional 8-bit ASCII
ASCII
The American Standard Code for Information Interchange is a character-encoding scheme based on the ordering of the English alphabet. ASCII codes represent text in computers, communications equipment, and other devices that use text...
paper tape
Punched tape
Punched tape or paper tape is an obsolete form of data storage, consisting of a long strip of paper in which holes are punched to store data...
punch/reader was also used, as this was a common storage medium at the time - where previous use of a computer had been limited to a teletype machine connected to mainframe
Mainframe computer
Mainframes are powerful computers used primarily by corporate and governmental organizations for critical applications, bulk data processing such as census, industry and consumer statistics, enterprise resource planning, and financial transaction processing.The term originally referred to the...
by telephone.
The system used a passive bus architecture with no motherboard – all electronics were contained on a number of cards interconnected by ribbon cable
Ribbon cable
A ribbon cable is a cable with many conducting wires running parallel to each other on the same flat plane. As a result the cable is wide and flat. Its name comes from the resemblance of the cable to a piece of ribbon.Ribbon cables are usually seen for internal peripherals in computers, such as...
. The only microprocessor offered was a 4 MHz
Hertz
The hertz is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of its most common uses is the description of the sine wave, particularly those used in radio and audio applications....
Z80A
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...
.
Memory
Memory was fitted in up to four banks of 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...
, each of either 4 KB
Kilobyte
The kilobyte is a multiple of the unit byte for digital information. Although the prefix kilo- means 1000, the term kilobyte and symbol KB have historically been used to refer to either 1024 bytes or 1000 bytes, dependent upon context, in the fields of computer science and information...
(4 × 1024 byte
Byte
The byte is a unit of digital information in computing and telecommunications that most commonly consists of eight bits. Historically, a byte was the number of bits used to encode a single character of text in a computer and for this reason it is the basic addressable element in many computer...
s) or 16 KB, although not every permutation was permitted. Typical configurations were 16 KB for cassette-based systems and 32, 48 or 64 KB of memory on disk-based systems. Main memory was not used by the text or graphics video cards, although memory on the video cards was bank switched
Bank switching
Bank switching is a technique to increase the amount of usable memory beyond the amount directly addressable by the processor. It can be used to configure a system differently at different times; for example, a ROM required to start a system from diskette could be switched out when no longer...
into a dedicated 1.5 KB address block.
The 380Z was also fitted with up to 5.25 KB of firmware
Firmware
In electronic systems and computing, firmware is a term often used to denote the fixed, usually rather small, programs and/or data structures that internally control various electronic devices...
, known as COS. On systems fitted with less than 64 KB or RAM the COS reserved 1 KB of system RAM, leaving the rest available to the user. On the 64 KB RAM system a total of 56 KB was available to the user, with the remainder used by COS or inaccessible because of the firmware 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...
, video card, and memory-mapped I/O
Memory-mapped I/O
Memory-mapped I/O and port I/O are two complementary methods of performing input/output between the CPU and peripheral devices in a computer...
.
Video
COS 3.4 (see below) and earlier systems came with a basic video cardVideo card
A video card, Graphics Card, or Graphics adapter is an expansion card which generates output images to a display. Most video cards offer various functions such as accelerated rendering of 3D scenes and 2D graphics, MPEG-2/MPEG-4 decoding, TV output, or the ability to connect multiple monitors...
providing a 40×24 text-only
Text mode
Text mode is a kind of computer display mode in which the content of the screen is internally represented in terms of characters rather than individual pixels. Typically, the screen consists of a uniform rectangular grid of character cells, each of which contains one of the characters of a...
monochrome display. Composite video
Composite video
Composite video is the format of an analog television signal before it is combined with a sound signal and modulated onto an RF carrier. In contrast to component video it contains all required video information, including colors in a single line-level signal...
output was provided for an external monitor, and an internal RF modulator
RF modulator
An RF modulator is a device that takes a baseband input signal and outputs a radio frequency-modulated signal....
provided a separate output to drive a television set. Later systems were supplied with an enhanced video card that was software-switchable between 40×24 and 80×24 character modes and supported a number of character attributes (underline, dim, reverse-video). Both card types were fitted with their own dedicated video memory.
In addition to the text-mode video card the system could be enhanced with a high-resolution
Image resolution
Image resolution is an umbrella term that describes the detail an image holds. The term applies to raster digital images, film images, and other types of images. Higher resolution means more image detail....
graphics (HRG) board. The board was fitted with a dedicated bank of 16 KB of video memory and supported two graphics modes:
- High resolution: 320×192 pixelPixelIn digital imaging, a pixel, or pel, is a single point in a raster image, or the smallest addressable screen element in a display device; it is the smallest unit of picture that can be represented or controlled....
s, 2 bits per pixelColor depthIn computer graphics, color depth or bit depth is the number of bits used to represent the color of a single pixel in a bitmapped image or video frame buffer. This concept is also known as bits per pixel , particularly when specified along with the number of bits used...
, 1 pagePage (computing)A page, memory page, or virtual page is a fixed-length contiguous block of virtual memory that is the smallest unit of data for the following:* memory allocation performed by the operating system for a program; and...
. - Medium resolution: 160×96 pixels, 4 bits per pixel, 2 pages.
A programmable lookup table
Lookup table
In computer science, a lookup table is a data structure, usually an array or associative array, often used to replace a runtime computation with a simpler array indexing operation. The savings in terms of processing time can be significant, since retrieving a value from memory is often faster than...
with an 8-bit output mapped the pixel value to one of 256 different colours (analogue RGB output) or intensities (composite video).
Output from the graphics board was mixed with output from the text-only video card, allowing text and graphics to be easily overlaid. The graphics output only covered the top 20 lines of the text display and therefore text output could be set to only use the bottom 4 lines if overlap was not desired.
Storage
Mass storageMass storage
In computing, mass storage refers to the storage of large amounts of data in a persisting and machine-readable fashion. Devices and/or systems that have been described as mass storage include tape libraries, RAID systems, hard disk drives, magnetic tape drives, optical disc drives, magneto-optical...
was either via cassette tape or floppy disk
Floppy disk
A floppy disk is a disk storage medium composed of a disk of thin and flexible magnetic storage medium, sealed in a rectangular plastic carrier lined with fabric that removes dust particles...
(which required a 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...
card). The cassette interface operated at either 300 bit/s (CUTS
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...
standard) or 1200 bit/s. COS 4.0 and later systems were not fitted with the cassette interface.
Early systems could be fitted with an optional single density
Single density
Single density, often shortened SD, is a capacity designation on magnetic storage, usually floppy disks. It describes the use of an encoding of information using Frequency modulation, also known as biphase mark code....
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,...
card that could interfaced to either internal 5¼-inch or external 8-inch floppy disk drives. Disk capacity was 80 KB per side on 5¼-inch disks and 250.25 KB per side on 8-inch disks. Double-sided disk drives were treated as two independent disks with a drive letter
Drive letter assignment
Drive letter assignment is the process of assigning alphabetical identifiers to physical or logical disk drives or partitions in the root filesystem namespace; this usage is now mostly found in Microsoft operating systems...
per side. CP/M used the first 4 tracks on 5¼-inch disks and the first 3 tracks on 8-inch disks, reducing the usable capacity of a single density, single-sided 5¼-inch disk to 72 KB.
Later systems (referred to as the 380Z-D) were fitted with a double density
Double density
Double density, often shortened DD, is a capacity designation on magnetic storage, usually floppy disks. It describes the use of an encoding of information, which can encode on average twice as many bits per time unit compared to single density...
Intelligent Disc Controller (IDC), which increased disk capacity to either 180 KB (48 TPI
Tracks per inch
Tracks per inch is a measure of magnetic resolution, in particular the number of individual tracks a floppy disk controller can use within a linear one-inch space.* 48 tpi* 96/100 tpi...
drives) or 360 KB (96 TPI drives) per side on 5¼-inch disks and 500.5 KB per side on 8-inch disks. Support for a "Winchester" hard disk drive could be provided using an intelligent Host Interface Board (HIB) that implemented a SASI interface. Hard disk systems were mainly used as file server
File server
In computing, a file server is a computer attached to a network that has the primary purpose of providing a location for shared disk access, i.e. shared storage of computer files that can be accessed by the workstations that are attached to the computer network...
s for networked LINK 480Z
LINK 480Z
The LINK 480Z was an 8-bit microcomputer produced by Research Machines Limited in Oxford, England, during the early 1980s.The 480Z used a Z80 microprocessor with up to 256 KB of bank-switched RAM...
systems.
Interface cards
The passive bus allowed a number of cards to be installed in the 380Z. All systems required:- CPU/RAM – holding the Z80A CPUCentral processing unitThe central processing unit is the portion of a computer system that carries out the instructions of a computer program, to perform the basic arithmetical, logical, and input/output operations of the system. The CPU plays a role somewhat analogous to the brain in the computer. The term has been in...
, firmware ROMs, and up to 32 KB of RAM. The card also provided a parallel Centronics printer port (not always connected). - Video, either a VDU-40 or VDU-80 card – providing the 40×24 or the switchable 80×24/40×24 character text displays, respectively.
Other cards were optional, and included:
- RAM – a second CPU/RAM board, with processor and ROMs omitted, holding up to a further 32 KB of RAM.
- Floppy Disc Controller (FDC) – a single density disk controller, which also provided an 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...
serial interface (SIO-4). - Intelligent Disc Controller (IDC) – a double density disk controller with its own dedicated microprocessor.
- High Resolution Graphics (HRG) – up to 320×192 pixels.
- Host Interface Board (HIB) – for hard disk support.
- 380Z Network Interface Board (380Z-NET) – a proprietary 800 kbit/s network interface used to interconnect to a network of LINK 480Zs.
- Serial Interface-1 (SIO-1) – available as the SIO-1A (RS-232) or SIO-1B (20 mA current loopCurrent loopA current loop describes two different electrical signalling schemes.- Digital :For digital serial communications, a current loop is a communication interface that uses current instead of voltage for signaling...
). - Serial Interface-2 (SIO-2) – available as the SIO-2 (RS-232) or SIO-2B/SIO-3 (20 mA current loop).
- Serial Interface-4C (SIO-4C) – providing an SIO-4 interface on cassette systems without the FDC card.
- IEEE-488IEEE-488IEEE-488 is a short-range digital communications bus specification. It was created for use with automated test equipment in the late 1960s, and is still in use for that purpose. IEEE-488 was created as HP-IB , and is commonly called GPIB...
Interface. - PIO/RTC Interface Development Board – providing a Z80 PIO and Z80 RTC.
- Analogue I/O Board – providing 16 input channels and 2 output channels.
Boot monitor
The system firmware contained only a basic monitor program, known as COS (standing for Cassette Operating System in the COS 3.4 and earlier systems and Central Operating System in the later disk-only systems). The monitor could be used to load application programs, such as BASICBASIC
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....
, from cassette or to boot
Booting
In computing, booting is a process that begins when a user turns on a computer system and prepares the computer to perform its normal operations. On modern computers, this typically involves loading and starting an operating system. The boot sequence is the initial set of operations that the...
the disk operating system. COS also provided a software front panel
Front panel
A front panel was used on early electronic computers to display and allow the alteration of the state of the machine's internal registers and memory. The front panel usually consisted of arrays of indicator lamps, toggle switches, and push buttons mounted on a sheet metal face plate...
allowing the display of registers and memory, and supporting breakpoint
Breakpoint
In software development, a breakpoint is an intentional stopping or pausing place in a program, put in place for debugging purposes. It is also sometimes simply referred to as a pause....
s and single-stepping of machine code.
The COS monitor was stored in either 4 KB (COS 3.4 and earlier) or 6 KB (COS 4.0 and later) of ROM, although in the latter case only 5.25 KB was mapped into addressable memory.
COS services
COS provided a number of basic hardware control functions, such as keyboard input, writing text to the video card and disk input/outputInput/output
In computing, input/output, or I/O, refers to the communication between an information processing system , and the outside world, possibly a human, or another information processing system. Inputs are the signals or data received by the system, and outputs are the signals or data sent from it...
. COS functions were called by means of the Emulator Trap
Trap (computing)
In computing and operating systems, a trap, also known as an exception or a fault, is typicallyThere is a wide variation in the nomenclature...
(EMT) pseudo-opcode
Opcode
In computer science engineering, an opcode is the portion of a machine language instruction that specifies the operation to be performed. Their specification and format are laid out in the instruction set architecture of the processor in question...
, which used the Z80 RST 30H instruction to call
Subroutine
In computer science, a subroutine is a portion of code within a larger program that performs a specific task and is relatively independent of the remaining code....
the EMT handler function. The EMT handler read the first byte following the RST 30H instruction to determine which EMT function was being requested; all parameters were passed in registers. A call-relative pseudo-opcode was also implemented using RST 28H.
Main COS versions
COS versions were mainly tied to the new hardware functions they supported.- COS 2.3 – cassette-only, 40×24 video card.
- COS 3.0 – floppy disk support.
- COS 3.4 – main COS version supporting single density disks and the 40×24 video card.
- COS 4.0 – 80×24 text display, no cassette support.
- COS 4.2 – double density disk drives (380Z-D).
Operating systems
The main disk operating systemDisk operating system
Disk Operating System and disk operating system , most often abbreviated as DOS, refers to an operating system software used in most computers that provides the abstraction and management of secondary storage devices and the information on them...
was 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...
, initially CP/M 1.4 and later CP/M 2.2. MP/M
MP/M
MP/M was a multi-user version of the CP/M operating system, created by Digital Research developer Tom Rolander in 1979. It allowed multiple users to connect to a single computer, each using a separate terminal....
II was used on the file server version, which supported a network of LINK 480Z computers using CP/NET.
Application software
Many standard CP/M applications were available, such as WordStarWordStar
WordStar is a word processor application, published by MicroPro International, originally written for the CP/M operating system but later ported to DOS, that enjoyed a dominant market share during the early to mid-1980s. Although Seymour I...
. Research Machines also produced their own assembler
Assembly language
An assembly language is a low-level programming language for computers, microprocessors, microcontrollers, and other programmable devices. It implements a symbolic representation of the machine codes and other constants needed to program a given CPU architecture...
(ZASM), text editor
Text editor
A text editor is a type of program used for editing plain text files.Text editors are often provided with operating systems or software development packages, and can be used to change configuration files and programming language source code....
(TXED) and BASIC interpreter
Interpreter (computing)
In computer science, an interpreter normally means a computer program that executes, i.e. performs, instructions written in a programming language...
.