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Manufacturer Tandy Radio Shack
Model TRS-80 Model I
Date Announced 1977
Date Canceled 1981
Number Produced Hundreds of Thousands
Country of Origin USA
Price About $600 for the base machine with display
Current Value $25-$250
Processor Zilog Z80
Speed 4 MHz
RAM 4K to 16K internally, 32K more with the expansion interface
ROM 4K (12K on Level II)
Storage Cassette tape, 5.25" floppy disks (optional)
Expansion TRS-80 Expansion Base
Bus N/A
Video 64 x 24 text, 128x48 graphics (modified text) on a monochrome monitor
I/O Parallel and Serial with expansion unit
OS Options TRS-DOS, NewDOS, others.
Notes The TRS-80 was one of the first "complete" personal computers available. It was introduced at around the same time as the Commodore Pet 2001 and the Apple II and competed with those machines directly.
Related Items in Collection Expansion Interface, Disk drive, some software, most manuals, TRS-80 Model I without the Numeric Keypad
Related Items Wanted Additional software, disk drives, voice synth unit, other Tandy peripherals (modem, hard drive, etc.)

The TRS-80 Model I came in several different versions. You could get the machine either with or without a numeric keypad and as a Level I (base) or Level II (upgraded BASIC and RAM) machine. The Level I model had a 4K BASIC with very limited capabilities. The Level II version had a 12K BASIC which was far more useful.

This machine is a Model I, Level II with the numeric keypad, expansion interface, drives and (flakey) monitor.

Thank you to Bob Wickman who donated this machine.

Another TRS-80 was added to the collection. This one came boxed in (mostly) original packages with two aftermarket drives, a Hayes 300 baud modem and more.

TRS-80 Model I System 2
TRS-80 Model I System 2 in boxes

(Submitted January 30, 2012 10:32:38 by Matthew)

There's this guy on Craigslist in my city trying to sell this for $4,000. What a joke. l

(Submitted August 27, 2011 01:55:10 by Ken Teramura)

I still use the TRS 80 and I am looking for printers. Okidate 300 or 390 or 82 if anyone has one. Email me at

(Submitted November 8, 2010 13:15:17 by Lee)

I have TRS-80 model I Level 2,2 floppy drives, many extras like a modem I, Quick Printer (thermal paper), a Dynatyper (used with a typewriter, it has plungers to do the typing) also manuals and magazines from that era. Many original boxes. Live near Chicago. All for sale, Best offer.

(Submitted November 3, 2010 12:19:33 by chris)

Any idea how much this might be worth if anything?

16k TRS-80 Color Computer I

(Submitted September 22, 2010 05:15:10 by Gary H)

The Step 1 and Step 2 terms being used is not exactly correct. It is/was officially Level 1 and Level 2. You can buy a Trs80 Level 1 or level 2.

(Submitted June 6, 2010 11:53:56 by Ken Byars)

I have an old TRS - 80 model 12 computer that belonged to my father. Is anyone interested in this unit for parts or whatever. Don't know if it works. You can have if you get back to me in time. ken @

(Submitted June 4, 2010 18:26:56 by Nubo)

Spent many an hour coding for the TRS-80. Basic, and then started coding the heavy subroutines in Assembler -- so much faster!! You really learned how to optimize back then. I remember how clueless people were about software. I bought a game on tape from a Radio Shack and it wouldn't load due to a bad tape. The salesman and even the manager insisted the program was sold as is! I remember writing a nice hot-air balloon simulation/game that I wish I still had.

(Submitted May 16, 2010 05:55:14 by Michael South)

My first computer was a Trash-80 L-1 I talked my Grandfather into buying me. It came with a really, really excellent BASIC manual--my Mom taught herself with it. If anyone has a copy of that manual, *please* make a copy, or donate it to Erik's collection.

(Submitted May 4, 2010 18:16:13 by David)

Hello. I'm buying a TRS-80 from somebodya nd I'm wondering if I need to ship a whole CRT screen when I have a CRT TV at home. Can these computers be plugged into a normal TV's aerial socket??

(Submitted April 8, 2010 23:39:00 by David)

I recently got my dad's TRS 80 II complete with a box of discs, 1000 lb. printer and the expansion base and I think it's beautiful. It still has the plastic covers and it's as bright and shiny as the day he brought it home and we watched as he booted up a spread sheet. Turns out that's about all it did and I lost interest in computers until the 286 came out. Unfortunately I'm getting a boot error MF which means a memory problem. I've taken out each of the 4 panels and shot them and the connectors with air and re seated them but to no avail. I guess the reason it's so clean is because it was never used and moisture has done it's damage. Too bad.

(Submitted April 7, 2010 08:16:39 by Brian Deuel)

We used to have these in high school. The fun part was ejecting the 8 floppies. If you flipped the latch just right, you could launch them across the room at a fairly rapid clip. Not good for the floppy, but fun nevertheless. I learned Z80 assembly on one of the successor machines, the Model III.

(Submitted February 10, 2010 09:33:40 by Kathleen Thomas)

TRS-80 complete Used to have one of these and programmed it (to the max)it to create a moving image of one of my sculptures, with random sound! Great little machine -- I still have the code and would like to run it and make a video of the moving image -- is there any way I could rent one of these -- pay shipping, back and forth + fee/deposit? Thanks -- so happy to see your site. Kathleen

(Submitted November 25, 2009 20:47:16 by Billy)

There used to be a magazine around during the era of these machines, it was called Rainbow if i am correct and it had pages with code that was already compiled and just needed to be input into the machine and stored on magnetic cassette tape, the resulting code would give you a game usually or some cool graphics for the time, I can remember very clearly entering thousands of lines of strange code in an after noon or evening with my father and some siblings. I would live to see an online archive of those magazines.

(Submitted August 25, 2009 20:26:56 by (a

I think you should update the specifications table, the TRS-80 Model 1 COULD use hard disks.

(Submitted May 1, 2008 12:02:06 by Gary H)

I ran a bbs for 2-3 years on a trs-80 model 1 (Horizon in the bay area if anyone remembers). I had 3 80 track double sided drives overtracked to 84 tracks running the newdos/80 operating system in addition to the 40 track ds drive used as the boot drive. It was one heck of a system back then. The only issues where the tin contacts which corroded and caused reboot/hang issues and the monitor which was intermitten. I would sometimes have to slap the monitor HARD to get it to display when it flickered off.

(Submitted February 28, 2008 18:14:17 by Bob Whitney)

I purchased my TRS-80 in 1977. I eventually purchased an expansion interface (Not Tandy), 2 floppy drives (single sided) and an Epson MX-80 printer. I also found out that I could use both sides of the floppies by punching holes in the disks. I also used Electric Pencil and Visicalc along with a neat game , Taipan, which actually had graphics showing ships sinking. Looking back, it was quite an experience and it helped me to understand computing and helped me on the job.

(Submitted August 26, 2007 23:17:45 by dean)

The different versions were called LEVELS *not* steps. Level 1 and Level 2.

(Submitted January 27, 2007 19:31:32 by Todd)

I still have my TRS-80 from when I bought it new in 1978. Upgraded to 16k LII but could never afford the EI and disks as a high school student. I have given my TRS a new purpose in life as the brains behind the resurrection of my college invention: a beer drinking game. You can see it on Google video at or search for Electronic Quarters. I used the TRS32 emulator to write the program file to an audio CD-R instead of a tape.

(Submitted December 2, 2006 08:46:57 by Sam Sorrell)

The Model I had a 64x16 display, not 64x24. Also, it was roughly a 2MHz machine (acutally something like 1.77MHz), not a 4 MHz machine. Although I think there was an aftermarket mod that would give you close to 4MHz.

(Submitted September 29, 2006 21:56:06 by Tony)

I bought my first TRS-80 Model I keyboard in the UK in 1980. It was sold by a third party who imported it without screen or tape player - and an RF modulator to enable it to be plugged into a standard UK TV. Opening it up it said it was a level I 4K machine, but it had been upgraded to Level II 16K. I upgraded it with low power chips to 48K - and found that if I cut out the logo on the left of the keyboard the numeric keyboard sockets were there - I bought some keys and created my own numeric keypad by soldering them to the motherboard. Adding a non-standard (Gnomic) interface enabled me to plug in disk drives and a printer, and when Visicalc was introduced for the machine it was invaluable to me as an accountant.

(Submitted August 18, 2006 11:27:18 by Dave Lay)

I have a TRS80 Model II with desk, expantion drive and printer that I paid more than $8K for new. It is in great condition and I am interested to know if there is any market for this complete unit.

(Submitted August 12, 2006 22:39:47 by Jeff)

I have a TRS80 Model II with built-in dual 8 drives, plus the quad 8 external unit, for sale.

(Submitted August 12, 2006 07:23:03 by joe)

i bought mine with 16k (deluxe version) lol for 950 bucks still had it and fired it up here and there until 2002 man i long for those days again

(Submitted August 12, 2006 06:06:32 by Caranne)

My father gave me a TSR-80 after he upgraded to a IBM-compat. He was always into technology. i.e.- as soon as he could buy a 20 moniter in the 1990's he did, for $2000. That was when a 15 could be had for $300+/-. Anyway- never could do much with it- I think I still know BASIC, learned it in 8th grade... The thing I remember most about it is when I had my pet Macaw in my bedroom, I took a nap and woke up to find a hole in the dust cover and half the keys pulled off.

(Submitted March 2, 2006 14:46:40 by Sam Brooks)

I have a Trash 80 Model I w/expansion interface, LII Basic and 48K, monitor and Siemens floppy. Has some kind of I/O problem - won't read or write to floppy, but is functional otherwise. I don't have any use for it - e-mail me if you want it for the cost of shipping it to you.

(Submitted August 18, 2005 12:10:04 by Thenamir)

I learned BASIC on a TRS-80 Model I in 1979 by visiting the Radio Shack almost daily -- chose my profession (programming) because of it.

I found a Model I in a mover's trash pile, keyboard and monitor, but no power cable for the keyboard -- the one with the 5-pin connector. Anyone know where I can find one? I'd like to see if it works. Monitor seems to power up OK.

(Submitted July 6, 2005 21:54:26 by Robb Doggie)

Yep, I had a trash 80. Paid $25 bones for it in 95. Which at that time made it rather obsolete. Nice toy though. Used endless loop cassettes, and had a strange compartment in the keyboard. Almost looked like I could stick a few D sized batts there. Never had the gadgets like they had in war games..

(Submitted April 2, 2005 07:12:49 by Robert)

In addition- my TRS 80 is the one piece model- with monitor & keyboard together. This sold at Radio Shack in Glendale Calif in 1980 for $2,000. + tax. ARRRGH Nice site you have..

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