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title, categories, types, origins, years, cpus, params
title categories types origins years cpus params
Tandy Radio Shack TRS 80 MODEL III
Computers
Home Computer
U.S.A.
1981
Zilog Z80 then Z80A
name image company company_name specs tabs forum_thread photos adverts hardware emulators links docs related software oc_id source
TRS 80 MODEL III /media/museum/photos/tandy_trs80-model3_1.jpg /companies/tandy-radio-shack Tandy Radio Shack
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NAME TRS 80 MODEL III
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MANUFACTURER Tandy Radio Shack
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TYPE Home Computer
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ORIGIN U.S.A.
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YEAR 1981
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END OF PRODUCTION Unknown
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BUILT IN LANGUAGE TRS-80 Level II BASIC
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KEYBOARD Full-stroke keyboard with separated numeric keypad
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CPU Zilog Z80 then Z80A
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SPEED 2.03 MHz
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RAM 16 KB (up to 48 KB)
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ROM 14 KB
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TEXT MODES 32 or 64 columns x 16 lines
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GRAPHIC MODES 128 graphic characters
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COLORS monochrome
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I/O PORTS Tape (500 or 1500 bauds), Centronics, RS232
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BUILT IN MEDIA Zero, one or two 5.25'' disk-drives.
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OS TRS DOS (other OSes were available : New DOS, LDOS, MultiDOS, ...)
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POWER SUPPLY Built-in power supply unit
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PERIPHERALS Various Tandy peripherals
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PRICE No disk model : AU$1450 (Australia, 1981)\ $2495 in 1984 for a complete system with 2x360 KB drives, TRSDOS, 64kb Ram, software and printer
photos
adverts
hardware
software
emulators
links
docs
38
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REBADGED VERSION A rebadged version sold by ADS Co. under the name DATAMAX. Thanks to **Jon Gilmore** /media/museum/photos/tandy_model3_adsclone_1.jpg
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TYPING SCHOOL In a few years traditional typewriters were replaced with computers. This revolution started around 1985. At the time, this school of the Pigier group was equiped with Tandy TRS80 models 1 and 3 /media/museum/photos/tandy_trs80mod3_typingcourse_1.jpg
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ISAAC ASIMOV AD #1 This surprising advert is dated 1982. /media/museum/pubs/tandy_trs80-model3_pub_1.jpg
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ISAAC ASIMOV AD #2 Advert said: Our word processing system changed Isaac Asimov's mind about writing...\ **"I may never use a typewriter again!"** Isaac likes the time he saves using SuperSCRIPSIT, our newest word processing program... /media/museum/pubs/tandy_model3_pub_2.jpg
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US ADVERT APR. 1982 Courtesy of **[Attached](http://www.aci.com.pl/mwichary/)** /media/museum/pubs/tandy_model3_pub_s3.jpg
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U.S. AD (1982) /media/museum/pubs/tandy_model3_pub_1.jpg
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FRENCH ADVERT (1982) /media/museum/pubs/tandy_trs80-model3_dossier31.jpg
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FRENCH ADVERT (JAN. 1982) /media/museum/pubs/tandy_trs-80_model1_pub_avocats.jpg
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REMOTE UNIT ACTIVE Serial# 26-1210 This rare unit is meant for teachers to control up to 16 TRS-80 Model 1 from a another TRS-80 equiped with min-disk. All the controled TRS-80 model 1 must be equiped with Level II. It cost 2895fr (France, 1981) /media/museum/hardware/tandy_trs80-m1_remote-unit-active.jpg
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NETWORK II BOX p/n 26-1211 This box allowed up to 16 TRS computer to be networked. Three network boxes were released by Tandy (I, II and III).\ The Network II required verbal communication between the server operator and the remote user, and data transfer had to be completed one user at a time.\ The network III allowed automated control of the network so that users could easily access programs and data stored on the server's storage device. Thanks to **David Sutherland** for the pictures. /media/museum/hardware/tandy_network2_s1.jpg
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DMP-200 80-column, 100 cps dot matrix printer. /media/museum/hardware/tandy_model3_dmp200_s1.jpg
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DAISY WHEEL PRINTER II Serial# 26-1158 This is a high-quality printer meant to be used with wordprocessors. Some interchangeable daisy-wheels were available (Courrier, Elite, Madeleine). It could print 163 characters per line (34cm), at a 43 cps rate. It cost 9595fr (France, 1981) /media/museum/hardware/tandy_trs80-m1_daisy-wheel-printer-2_1.jpg
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LINE PRINTER I Ref# 26-7017 This printer was a custom version of the Oki Microline 80.\ Printed lower and upper case on paper rolls or listing paper (24cm wide) from 40 to 80 columns/line, at a speed rate of 28 lines/minute. It cost 716 Euros in 1981 (France). /media/museum/hardware/tandy_model1_lineprinter1_s1.jpg
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LINE PRINTER III Serial# 26-1156 This printer can print lower and upper case, at a speed rate of 120 c/s, on paper up to 38cm wide. It is conceived for intensive use ! It cost 9950fr in 1981 (France). /media/museum/hardware/tandy_trs80-m1_line-printer-3_1.jpg
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LINE PRINTER VI Serial# 26-1166 This large printer can print lower and upper case, graphic characters and symbols at a speed rate of 100 c/s ! This is definately a professional printer. It cost 5495fr in 1981 (France). /media/museum/hardware/tandy_trs80-m1_line-printer-6_1.jpg
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TP-10 THERMAL PRINTER Box /media/museum/hardware/tandy_trs80_tp-10_thermal-printer_box.jpg
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15 MB HARD DISK UNIT /media/museum/hardware/tandy_model3_15mbhddunit.jpg
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EXATRON Stringy Floppy drive The Exatron Stringy Floppy (ESF) was a low-cost data—storage system that fitted the gap, between cassettes and disk drives.\ The system was based on a miniature endless—loop tape cartridge called a "wafer".\ The amount of data that could be recorded on a wafer depended on the length of tape in it, typically, a 50—foot wafer could hold at least 40 KB of programs or data. **Matt** reports to us:\ A curiousity about the model 1, CPU SPEED had a direct relatonship with STORAGE CAPACITY. if you doubled the clock speed of your MODEL 1 CPU you doubled the amount of data you could store on your stringy floppies. this is a feat that no other computer no matter how many ghz you have in your PC can do today without using compression. Thanks to **David Sutherland** for the pictures /media/museum/hardware/tandy_model3_exatronwafer_s1.jpg
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EXATRON DRIVE FOR THE MODEL 3 Thanks to **www.turnkit.com/computers** /media/museum/hardware/tandy_model3_exatronwafer3_s1.jpg
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David Keil's TRS-80 Model III/4/4P Emulator Page http://discover-net.net/~dmkeil/trs80/model4.htm MS DOS This program emulates a complete TRS-80
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Matthew Reed's TRS-80 Emulator Web Site http://www.arrowweb.com/mkr/ MS DOS This page offers shareware versions of a TRS-80 Model 4 emulator and a TRS-80 Model 1-2 emulator
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TRS-80 Model III/4 Emulator http://www.vavasour.ca/jeff/trs80.html#model4 MS DOS This TRS-80 Model III/4 Emulator is a commercial product
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xtrs: TRS-80 Model I/III/4 Emulator for Unix http://www.tim-mann.org/xtrs.html Unix / Linux xtrs is a Radio Shack TRS-80 Model I/III/4/4P emulator for Unix and the X Window System
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2nd life TRS 80 model III emulator http://www.users.zetnet.co.uk/atari_shack/emul8.htm Atari TRS 80 model III emulator for Atari ST systems
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TRS-80 Level I BASIC in a browser http://www.vavasour.ca/jeff/trs80.html#simulator Other platform With this Java emulator, you'll be able to write a BASIC program directly in your browser!
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Ira Goldklang's TRS-80 Revived Pages http://www.trs-80.com/trs80-e.htm Multiplatform A complete list of TRS-80 emulators for various platforms !
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MESS http://www.mess.org Multiplatform MESS emulator also emulates a TRS-80 systems
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8bit-micro.com - Online TRS-80 Computer Magazine HTTP://WWW.8BIT-MICRO.COM Online Magazine dedicated to the TRS-80 and other Vintage - Monthly Issues
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David's TRS-80 Page http://freespace.virgin.net/david.sampson/
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Ira Goldklang's TRS-80 Revived Pages http://www.trs-80.com/ Lof of infos about all TRS-80 computers
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Java TRS-80 Model 1 BASIC Interpreter http://ganley.org/software/trs80.html
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Mike's Personal Computer Museum http://personal.nbnet.nb.ca/mclays/trsmod1.html Level 1 & 2 Basic summaries, Tandy time-lines, price-list, etc ... !
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RadioShackCatalogs.com http://www.RadioShackCatalogs.com Here, you can actually/virtually flip-through the pages to view the content of every RadioShack catalog!
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The TRS-80 Home Page http://www.kjsl.com/trs80 Full of infos
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Tim Mann's TRS-80 Page http://www.tim-mann.org/trs80.html Infos, tools and home of xtrs, a Model I/III/4 emulator for Unix
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Web Wiz CAPTCHA http://www.webwizcaptcha.com Discussion about Tandy computers
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TRS-80 MODEL III - OPERATION AND BASIC LANGUAGE OPERATION MANUAL null /media/museum/docs/couvs/tandy_trs80model3_operation-and-basic-language-reference-manual.jpg **TRS-80 MODEL III - OPERATION AND BASIC LANGUAGE OPERATION MANUAL**\ written by Radio Shack  compiled/archived by Wade Fincher\  type of document : PDF\  size : 6 MB\  source : [WinTRS80 homepage](http://asub.arknet.edu/wade/)
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TRS-80 MODEL III - DISK SYSTEM OWNER'S MANUAL null /media/museum/docs/couvs/tandy_trs80-model3_disk-system-operation-manual.jpg **TRS-80 MODEL III - DISK SYSTEM OWNER'S MANUAL**\ written by Radio Shack  compiled/archived by Wade Fincher\  type of document : PDF\  size : 18 MB\  source : [WinTRS80 homepage](http://www2.asub.arknet.edu/wade/)
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GRAPHICS BOARD MANUAL http://www2.asub.arknet.edu/wade/m3graphics.htm /media/museum/docs/couvs/tandy_trs80-model3_graphics-board-manual.jpg [**GRAPHICS BOARD MANUAL**](http://www2.asub.arknet.edu/wade/m3graphics.htm)written by Radio Shack  compiled/archived by Wade Fincher\  type of document : PDF\  source : [WinTRS80 homepage](http://www2.asub.arknet.edu/wade/)
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DISK MODIFICATION KIT - SERVICE MANUAL http://www2.asub.arknet.edu/wade/m3diskinstall.htm /media/museum/docs/couvs/tandy_trs80-model3_modification-kit.jpg [**DISK MODIFICATION KIT - SERVICE MANUAL**](http://www2.asub.arknet.edu/wade/m3diskinstall.htm)written by Radio Shack  compiled/archived by Pete Bumgardner\  type of document : PDF\  source : [WinTRS80 homepage](http://www2.asub.arknet.edu/wade/)
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MDX-6 DISK UPGRADE FOR MODEL III http://www2.asub.arknet.edu/wade/mdx6.htm /media/museum/docs/couvs/tandy_trs80-model3_mdx6-upgrade.jpg [**MDX-6 DISK UPGRADE FOR MODEL III**](http://www2.asub.arknet.edu/wade/mdx6.htm)written by Micro-Design  compiled/archived by Wade Fincher\  type of document : PDF\  source : [WinTRS80 homepage](http://www2.asub.arknet.edu/wade/)
/museum/radionic-model-r1001
/museum/sysdata-eletronica-jr
/museum/tandy-radio-shack-trs-80-model-12
/museum/tandy-radio-shack-trs-80-model-16
/museum/tandy-radio-shack-trs-80-model-4
/museum/tandy-radio-shack-trs-80-model-4p
/museum/tandy-radio-shack-trs-80-model-i
/museum/tandy-radio-shack-trs-80-model-ii
/software/attack-force
/software/super-nova
/software/typing-tutor
18
url date
https://web.archive.org/web/20230129160404/http://www.old-computers.com/museum/computer.asp?c=18 2023-01-29

The model 3 is generally regarded as the successor to the Model 1. Its two 5.25" floppy disk drives could convert model 1 disks.

Initially Radio Shack wanted to sell both the model 1 and 3 at the same time, but the FCC forced them to stop selling model 1. Is so they were discontinued because of the excessive radio noise that they put out.

However, the Model 3 wasn't FULLY compatible with the model 1. There were differences in ROM which meant some programs had to be converted, especially those machine language ones that made ROM calls.


Model III configurations, by Dave Thompson:
TRS-80 Model III was sold in multiple configurations.
No hardrive configurations included:
Model III with Level 1 ROM, 8k RAM sold for US$799. Model III with Level 2 ROM, 16k RAM sold for $999.
The first floppy drive cost $849, and could store 168k. The second drive was cheaper, and could store more. The price difference is due to the first one included the drive controller. The increased space on the second drive (189k) was due to the first drive must also contain some TRS-DOS (the operating system).

Brandt Daniels adds:
There was also a TRS-80 VideoTex Computer terminal in 1980.

Mark Fowler reports:
I worked for a company in 1982 that had integrated a 5MB, and later a 10MB hard disk into the TRS80 Model III. It was then programmed in FORTRAN-66 as a dedicated medical records system, to mimic the pegbook accounting system in use in the 1980's. We introduced green phosphor, and later amber phosphor display tubes. Some systems were used with a modem to do simple email-type applications, and to access various bulletin boards.