Tandy 2000
Encyclopedia
The Tandy 2000 was a personal computer
introduced by Radio Shack
in late 1983 which used the 8 MHz Intel 80186
microprocessor
. By comparison, the IBM PC XT (introduced in March 1983) used the older 4.7 MHz 8088 processor, and the IBM PC AT (introduced in 1984) would later use the newer 6 MHz Intel 80286
. Due to the more efficient design of the 80186, the Tandy 2000 ran significantly faster than other PC compatibles on the market, and slightly faster than the PC AT. (Later, IBM upgraded the 80286 in new PC AT models to 8 MHz.)
While touted as being compatible with the IBM XT, the Tandy 2000 was different enough that most software that was not purely text-oriented did not work properly. It differed by having a Tandy-specific video mode (640x400, but not related to or forward-compatible with the 1987 VGA standard), keyboard scan codes, and other differences. The computer was poorly supported by Radio Shack in the following years; eventually the remaining unsold computers were converted into the first Radio Shack Terminals (which coincidentally had been one of the backup plans for the original TRS-80
Model I).
The Tandy 2000 was the only computer sold by Radio Shack that had both the "Tandy" and "TRS-80" logos on its case, marking the beginning of the phaseout of the "TRS-80" brand.
Color Monitor CM-1 listed for ~$799 and required a $300 color display card in one of the 5 card slots.
Green Screen VM-1 for ~$300 was used with out the color display plug in card and gave a very fast text display rate , a 'HOLD' key on the keyboard could be used to pause text output as it was much to fast at times.
driver, which was a software wrapper that virtualized the serial hardware (see also DEC Rainbow), allowing the terminal software to work on a wider variety of hardware.
Luckily many terminal programs were available for the Tandy 2000 and many were used to log on to BBS
's, e-mail, etc.
format. Very few other computers used this disk format, which is double-sided 80-track using MFM encoding. Standard 360K drives use a 40-track MFM format, while 1.2M high-density 5.25" drives use 80 tracks but also fit more sectors into each track using higher frequency signals. 80 or 40 is the number of tracks per side, and each track on an 80-track disk is half as wide as one on a 40-track disk. The Tandy 2000 720K drives use standard 360K double-sided double-density diskette media, albeit certified to a higher standard for 80-track use. As compared to a 360K double-density disk, the standard of the time on IBM compatible systems, a Tandy 2000 720K disk has a track format that is exactly the same, except that each track is half as wide. The doubling of the number of tracks doubled the data capacity of the disk; for this reason, by contrast with the 360K double-density format, the 720K 80-track format is sometimes called "quad-density".
The 720K drives could read and write 360K floppies, but with caution required if the disks were to be subsequently used in a 360K drive. The narrow tracks written by a 720K 5.25" drive would not completely erase the wider tracks previously written by a 360K drive. (5.25" 1.2M high-density drives, which are also 80-track, have the same issue when exchanging disks with 360K drives. 3.5" drives do not have any similar problem because all standard 3.5" formats are 80-track.) Generally, only new blank media, or media that has been wiped clean with a bulk eraser, can be written in 360K format by these 720K drives and then transferred to a 360K drive. The 720K drive itself would have no problem reading and writing any 360K-formatted disk, since its narrow heads would not pick up any residual half-tracks it had failed to erase.
There are hardware hacks to use 720K 3.5" floppy drives with a Tandy 2000, but it is unclear whether disks formatted in this way work with other PC compatibles.
that would run only on this machine. Standard MS- or PC-DOS
(for generic IBM-compatibles) would not run on a Tandy 2000. It was standard practice and Microsoft's expectation at the time that a customized version of MS-DOS would be prepared for each different machine, with I/O drivers designed for the hardware of that model. The highest version of DOS that Tandy Corporation released for the Tandy 2000 was 2.11.03, with a few minor 3rd-party patches after the fact. A modified version of Windows 1.0
was able to run on the Tandy 2000.
4.2 (WP5.1 could work with software patches), Lotus 1-2-3
, AutoCAD
, Lumena (from Time Arts) and shareware
office programs. Microsoft released a version of Xenix
for the Tandy 2000 (used with Tandy's network card).
Better BASIC for both the T2K and the PC was used to write BBS software for the T2K and later ported to the IBM-pc.
Radio Shack's 'DESKMATE' was used with the T2K and the Tandy-1000
based in Texas that had an extensive library of compatible software available for download; neither the BBS nor its web-based descendant is active today. FAQ @ CCHAVEN.COM
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...
introduced by Radio Shack
Radio shack
Radio shack is a slang term for a room or structure for housing radio equipment.-History:In the early days of radio, equipment was experimental and home-built. The first radio transmitters used a noisy spark to generate radio waves and were often housed in a garage or shed. When radio was first...
in late 1983 which used the 8 MHz Intel 80186
Intel 80186
The 80188 is a version with an 8-bit external data bus, instead of 16-bit. This makes it less expensive to connect to peripherals. The 80188 is otherwise very similar to the 80186. It has a throughput of 1 million instructions per second....
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...
. By comparison, the IBM PC XT (introduced in March 1983) used the older 4.7 MHz 8088 processor, and the IBM PC AT (introduced in 1984) would later use the newer 6 MHz Intel 80286
Intel 80286
The Intel 80286 , introduced on 1 February 1982, was a 16-bit x86 microprocessor with 134,000 transistors. Like its contemporary simpler cousin, the 80186, it could correctly execute most software written for the earlier Intel 8086 and 8088...
. Due to the more efficient design of the 80186, the Tandy 2000 ran significantly faster than other PC compatibles on the market, and slightly faster than the PC AT. (Later, IBM upgraded the 80286 in new PC AT models to 8 MHz.)
While touted as being compatible with the IBM XT, the Tandy 2000 was different enough that most software that was not purely text-oriented did not work properly. It differed by having a Tandy-specific video mode (640x400, but not related to or forward-compatible with the 1987 VGA standard), keyboard scan codes, and other differences. The computer was poorly supported by Radio Shack in the following years; eventually the remaining unsold computers were converted into the first Radio Shack Terminals (which coincidentally had been one of the backup plans for the original TRS-80
TRS-80
TRS-80 was Tandy Corporation's desktop microcomputer model line, sold through Tandy's Radio Shack stores in the late 1970s and early 1980s. The first units, ordered unseen, were delivered in November 1977, and rolled out to the stores the third week of December. The line won popularity with...
Model I).
The Tandy 2000 was the only computer sold by Radio Shack that had both the "Tandy" and "TRS-80" logos on its case, marking the beginning of the phaseout of the "TRS-80" brand.
Specifications
- 8 MHz Intel 80186
- 128KB RAM (expandable to 768KB, of which up to 256KB was located on the motherboard, or up to a maximum of 896KB with motherboard and ROM modifications)
- 1 or 2 720KB 5-1/4" floppy drives
- 10MB MFMModified Frequency ModulationModified Frequency Modulation, commonly MFM, is a line coding scheme used to encode the actual data-bits on most floppy disk formats, hardware examples include Amiga, most CP/M machines as well as IBM PC compatibles. Early hard disk drives also used this coding.MFM is a modification to the original...
full-height hard drive (upgradable to two 32MB half-height drives, or two 80MB drives with ROM modifications and third-party low-level formatting software) - Proprietary parallel printer port (requires adapter cable to connect to a Centronics-port printer)
- Proprietary serial port
- 4? card slots on the back could accept expansion boards without the need to open the case
- 256KB RAM card (up to 2 could be added for 768KB total; each card had two 128KB banks of nine 16KB RAM chips)
- Color Graphics Card
- Mouse/Clock Card
- Hard disk card with two ribbon cables to an outboard 10MB hard drive
- Network Card (BNC)
Compatibility issues
The Tandy 2000 was nominally BIOS-compatible with the IBM XT, which allowed well-behaved DOS software to run on both platforms. However, most DOS software of the time bypassed the operating system and BIOS and directly accessed the hardware (especially video and external ports) to achieve higher performance, rendering the software incompatible with the Tandy 2000.Graphics
The Tandy 2000's proprietary graphics hardware allowed a display of up to 640x400 (non-interlaced) pixels with 16 colors onscreen, which was a particularly high-resolution and colorful display for its day. CGA compatibility was hit or miss. The text-mode address space was in a different location but third party memory-resident software hacks remedied this by copying the PC-compatible text-mode memory to the Tandy 2000's text space at a rate of 5-10 times per second. This caused a bit of choppiness in the display, but worked fairly well.Color Monitor CM-1 listed for ~$799 and required a $300 color display card in one of the 5 card slots.
Green Screen VM-1 for ~$300 was used with out the color display plug in card and gave a very fast text display rate , a 'HOLD' key on the keyboard could be used to pause text output as it was much to fast at times.
Serial port
The serial port hardware was completely different from the PC-XT's. PC-compatible terminal emulation software had to either maintain strict BIOS usage of the serial hardware, or else use a FOSSILFOSSIL
FOSSIL is a standard protocol for allowing serial communication for telecommunications programs under the DOS operating system. FOSSIL is an acronym for Fido Opus SEAdog Standard Interface Layer. Fido refers to FidoBBS, Opus refers to Opus-CBCS BBS, and SEAdog refers to a Fidonet compatible mailer...
driver, which was a software wrapper that virtualized the serial hardware (see also DEC Rainbow), allowing the terminal software to work on a wider variety of hardware.
Luckily many terminal programs were available for the Tandy 2000 and many were used to log on to BBS
BBS
-Technologies:* Bulletin Board System, a computer that allows users to dial into the system over a phone line or telnet connection* BIOS Boot Specification, a system firmware specification related initial program load...
's, e-mail, etc.
Media
The floppy drives are a rare 720 KB 5-1/4" floppyFloppy
Floppy may refer to:* Floppy disk or floppy disk drive* Floppy disk controller* The Floppy Show* Mr. Floppy from the Sitcom Unhappily Ever After* Mr Floppy Australian rock band* Floppy a character from The Magic Key...
format. Very few other computers used this disk format, which is double-sided 80-track using MFM encoding. Standard 360K drives use a 40-track MFM format, while 1.2M high-density 5.25" drives use 80 tracks but also fit more sectors into each track using higher frequency signals. 80 or 40 is the number of tracks per side, and each track on an 80-track disk is half as wide as one on a 40-track disk. The Tandy 2000 720K drives use standard 360K double-sided double-density diskette media, albeit certified to a higher standard for 80-track use. As compared to a 360K double-density disk, the standard of the time on IBM compatible systems, a Tandy 2000 720K disk has a track format that is exactly the same, except that each track is half as wide. The doubling of the number of tracks doubled the data capacity of the disk; for this reason, by contrast with the 360K double-density format, the 720K 80-track format is sometimes called "quad-density".
The 720K drives could read and write 360K floppies, but with caution required if the disks were to be subsequently used in a 360K drive. The narrow tracks written by a 720K 5.25" drive would not completely erase the wider tracks previously written by a 360K drive. (5.25" 1.2M high-density drives, which are also 80-track, have the same issue when exchanging disks with 360K drives. 3.5" drives do not have any similar problem because all standard 3.5" formats are 80-track.) Generally, only new blank media, or media that has been wiped clean with a bulk eraser, can be written in 360K format by these 720K drives and then transferred to a 360K drive. The 720K drive itself would have no problem reading and writing any 360K-formatted disk, since its narrow heads would not pick up any residual half-tracks it had failed to erase.
There are hardware hacks to use 720K 3.5" floppy drives with a Tandy 2000, but it is unclear whether disks formatted in this way work with other PC compatibles.
Operating system
The Tandy 2000 required a specific version of MS-DOSMS-DOS
MS-DOS is an operating system for x86-based personal computers. It was the most commonly used member of the DOS family of operating systems, and was the main operating system for IBM PC compatible personal computers during the 1980s to the mid 1990s, until it was gradually superseded by operating...
that would run only on this machine. Standard MS- or PC-DOS
PC-DOS
IBM PC DOS is a DOS system for the IBM Personal Computer and compatibles, manufactured and sold by IBM from the 1980s to the 2000s....
(for generic IBM-compatibles) would not run on a Tandy 2000. It was standard practice and Microsoft's expectation at the time that a customized version of MS-DOS would be prepared for each different machine, with I/O drivers designed for the hardware of that model. The highest version of DOS that Tandy Corporation released for the Tandy 2000 was 2.11.03, with a few minor 3rd-party patches after the fact. A modified version of Windows 1.0
Windows 1.0
Windows 1.0 is a 16-bit graphical operating environment, developed by Microsoft and released on 20 November 1985. It was Microsoft's first attempt to implement a multi-tasking graphical user interface-based operating environment on the PC platform. Windows 1.0 was the first version of Windows...
was able to run on the Tandy 2000.
Software
Software packages that were released for the Tandy 2000, included WordPerfectWordPerfect
WordPerfect is a word processing application, now owned by Corel.Bruce Bastian, a Brigham Young University graduate student, and BYU computer science professor Dr. Alan Ashton joined forces to design a word processing system for the city of Orem's Data General Corp. minicomputer system in 1979...
4.2 (WP5.1 could work with software patches), Lotus 1-2-3
Lotus 1-2-3
Lotus 1-2-3 is a spreadsheet program from Lotus Software . It was the IBM PC's first "killer application"; its huge popularity in the mid-1980s contributed significantly to the success of the IBM PC in the corporate environment.-Beginnings:...
, AutoCAD
AutoCAD
AutoCAD is a software application for computer-aided design and drafting in both 2D and 3D. It is developed and sold by Autodesk, Inc. First released in December 1982, AutoCAD was one of the first CAD programs to run on personal computers, notably the IBM PC...
, Lumena (from Time Arts) and shareware
Shareware
The term shareware is a proprietary software that is provided to users without payment on a trial basis and is often limited by any combination of functionality, availability, or convenience. Shareware is often offered as a download from an Internet website or as a compact disc included with a...
office programs. Microsoft released a version of Xenix
Xenix
Xenix is a version of the Unix operating system, licensed to Microsoft from AT&T in the late 1970s. The Santa Cruz Operation later acquired exclusive rights to the software, and eventually superseded it with SCO UNIX ....
for the Tandy 2000 (used with Tandy's network card).
Better BASIC for both the T2K and the PC was used to write BBS software for the T2K and later ported to the IBM-pc.
Radio Shack's 'DESKMATE' was used with the T2K and the Tandy-1000
End of life
After Tandy essentially ceased support of the Tandy 2000, a group of users formed the Tandy 2000 Orphans, with software reviews, software and hardware hacks, and a shareware/freeware repository. There was also a BBSBulletin board system
A Bulletin Board System, or BBS, is a computer system running software that allows users to connect and log in to the system using a terminal program. Once logged in, a user can perform functions such as uploading and downloading software and data, reading news and bulletins, and exchanging...
based in Texas that had an extensive library of compatible software available for download; neither the BBS nor its web-based descendant is active today. FAQ @ CCHAVEN.COM