TRS-80 Model II Family

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TRS-80 Model II
TRS-80 model ii.jpg
A Tandy model II
Manufacturer: Tandy Corporation
Year Introduced: 1979
Form Factor: Desktop
Clock Speed: 4 MHz
Memory Size: 32 or 64 KB
CPU: Zilog Z80A
Successor(s): Model 12 and Model 16

The Tandy TRS-80 Model II Family was a high priced line of TRS-80 and Tandy computers. The were used almost exclusively as business machines. The line started in 1979 with the TRS-80 Model II, the successor in name and processor only to the original TRS-80 Model I.

TRS-80 Model II

The TRS-80 Model II was a great departure from the Model I. It came with a single-sided 500 KB 8 inch floppy disk drive. It originally ran a variation of TRSDOS and CP/M. Many accounting and other office programs were available for it, as well as a Basic compiler, Fortran, and COBOL. An interesting fact about the architecture of these computers is that it has a tiny boot ROM and the basic compiler is loaded off TRSDOS into memory. Also, it had a detached keyboard.


TRS-80 Model 16
Manufacturer: Tandy Corporation
Year Introduced: 1982
Form Factor: Desktop
Clock Speed: 6 MHz
Memory Size: 128 to 512 KB
CPU: Zilog Z80A and Motorola MC68000
Successor(s): Model 16B


TRS-80 Model 16

The TRS-80 Model 16 was an early dual processor machine. In addition, to the Z80A used for I/O and compatibility, it had a 16/32-bit Motorola MC68000 processor. This system wasn't very successful due to initial lack of 16-bit software.


TRS-80 Model 12
Manufacturer: Tandy Corporation
Year Introduced: 1982
Form Factor: Desktop
Clock Speed: 4 MHz
Memory Size: 64 KB
CPU: Zilog Z80A
Successor(s): Tandy 6000


TRS-80 Model 12

The TRS-80 Model 12 is an improved Model II with a double sided floppy disk drive, a green on black display, and an available expansion card cage which added 6 expansion slots.


TRS-80 Model 16B
Manufacturer: Tandy Corporation
Year Introduced: 1982
Form Factor: Desktop
Clock Speed: 6 MHz
Memory Size: 128 to 768 KB
CPU: Zilog Z80A and Motorola MC68000
Successor(s): Model 16B


TRS-80 Model 16B

The TRS-80 Model 16B is possibly the most famous model in the line. It is simply a Model 16 with minor improvements but what makes it so well-known is the fact that not only could it run XENIX but its XENIX systems were so popular that it was the top selling Unix-based computer in 1984 with over 40,000 units sold.


Tandy 6000
Manufacturer: Tandy Corporation
Year Introduced: 1982
Form Factor: Desktop
Clock Speed: 8 MHz
Memory Size: 128 KB to 768 MB
CPU: Zilog Z80A and Motorola MC68000
Successor(s): Tandy 6000


Tandy 6000

The Tandy 6000 was an improved model 16B with an internal 70 MB hard disk drive and expandable up to 1 MB in RAM.

Operating Systems

There were 3 major versions of TRSDOS available for the systems. Original TRSDOS, roughly based on Model I TRSDOS but with Microsoft Basic integrated into the OS; TRSDOS-II, a DOS designed specifically for the Model II family; TRSDOS-16, which is less of an operating system and more of a system overlay that allowed the execution of 16-bit TRSDOS software on the Model 16 and 16B. Very little software was made for TRSDOS-16. One TRSDOS clone was available, a Model II family compatible LS-DOS. Four or five versions of both CP/M and CP/M were available with the most popular being Pickles & Trout CP/M 2.2. The total game-changing OS available for the Model 16B and Tandy 6000 was Microsoft XENIX, a 16-bit Unix based on System III Unix.

Peripherals

An external floppy disk drive enclosure was available that held up to four drives. External hard disk drives were available in size from 8.4 to 70 MB. Possibly, the most interesting accessory made for the Model II was a special desk designed to hold the floppy drive enclosure.

Legacy

The Tandy 6000 was nominally replaced by the Tandy 3000, an Intel 80286 Compatible PC which ran SCO XENIX. Unfortunately, there isn't as much of a fan base for this series of machines as there is others but below there is a link for a huge archive and recently a TRS-80 emulator called trs80gp has been available which runs a lot of the series' software including XENIX.

External Links

Some information can be found:

A huge collection of software and documentation can be found at:

It is recommended that you clone the archive instead of downloading the zip file because it tends to fail otherwise.

The trs80gp emulator is available at:

Emulation Tutorials

A couple of tutorials to try: Installing TRSDOS-II 4.4 onto a Model II or 12 System With a Hard Drive and Installing XENIX on a Tandy 6000