
A Tandy / RadioShack TRS-80 Model 1 Clone - sohkamyung
http://www.glensstuff.com/trs80/trs80.htm
======
gregoryseattle
Ah the memories....

I cut my teeth on a TRS-80 Model 1 with 4K of RAM. I was like 13 or so and got
one in the late 70s. I learned BASIC on it, but quickly ran out of CPU and
memory with the interpreted BASIC and switched to Z-80 assembler. I didn't
have an assembler however, so would write out all of the Z-80 instructions by
hand on paper, then, when I thought I had debugged it enough on paper, I would
convert it to the hex OpCodes. At that point I would either use a small BASIC
program to POKE the hex into memory and run it, or after I got a hex editor, I
would use that to type in the hex values. Of course, all of this was saved to
cassette tapes! If there was a bug I would go back to the paper and figure out
where I went wrong. I still remember some Z-80 OpCodes to this day from the
countless hours of converting assembler to hex.

One really cool way I would use to debug programs, or at least know if they
were running, was to keep an AM radio next to the computer. The TRS-80/Z-80
would give off enough RF so you could "hear" the program running on the radio.
In fact, you could devise loops and delays in your assembler such that you
could "play" music on the radio. :-)

~~~
Starwatcher2001
I did pretty much the same, although I managed to get the 16k RAM version.
I've still got my old TRS-80 in the loft, eventually with the expansion box
and couple of disk drives. Each single-sided 5.25" floppy held a massive 90k,
then someone worked out that if you punched a timing hole in the cover in the
right place you could put the floppy in upside-down and use the other side
too.

Like you, I cut my teeth on the TRS-80 and wrote my first commercial program
around 1982, a graphics drawing tool (written in Z80). It sold maybe a dozen
copies, but was a start. I've got fond memories of EDTASM and T-BUG, the
assembler and debugger.

~~~
jlv2
I'm also have a similar background (although the first computer I used was my
school's PDP-8i via a teletype). I still have my Model I and all the assorted
accessories. I remember moving from EDTASM to Microsoft's Macro Assembler for
the Z-80 assembler I write.

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ineedasername
My first computer of any sort was a Tandy Color Computer that I got in the
early 90's on clearance at Radio Shack using birthday & Christmas gift money.

I think it cost $75, and I paid an extra few dollars for some old Basic
programming books & a few cartridges with games. It was my first experience
with programming, and I remember this fun sense of excitement when learning
very simple "hacks" like the infinite loop:

    
    
      10 print "Name"
      20 goto 10
    

I had no storage, no disk drive, everything was lost when I powered off, and
the games were awful (compared to NES & SNES) but it was a foundational
experience for me. Good times.

~~~
torgoguys
It was even better than that, if my recollection is correct. Those computers
came with a very readable BASIC tutorial book at no extra charge (at least for
the CoCo 1 and 2). I still remember the cartoon computer character that was
your teacher in the illustrations. Those books are how I first learned to
program.

~~~
brlewis
Much better for me because I had a cassete tape drive where I could save my
programs. It had a counter. I kept a piece of paper with the counter numbers
so I could fast forward/rewind to get to specific programs I'd saved on tape.

I made games on it. When BASIC wasn't fast enough for what I wanted to do I
looked into Assembly. I sent snail mail to Motorola asking where I could buy
the 6809E assembler manual, and they sent me one for free.

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jandrese
I never had a TRS-80, so I didn't know that absolute craziness with the lower
case characters. I get that someone wanted to save money by not adding the
chip for bit 6, but to add that note that you were intended to magic that bit
out of thin air seems absolutely insane.

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jhallenworld
I know someone who built a Model 1 clone in the 70s.. to get the ROM he went
to a Radio Shack store and ran a little BASIC program that printed it.

(This guy worked at HP, on their calculator chips).

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mixmastamyk
My 5th grade teacher had a TRS-80 in class and we would occasionally learn a
bit of programming or (I think) take quizzes on it. This was approximately
1981, talk about ahead of his time!

Around that time I got a VIC-20 for Christmas with cassette drive, a great
time to be alive.

Funny, almost a decade later in high school, I took a programming class and
they were still using the same computer, a TRS-80 all-in-one. Talk about
behind the times, haha.

(Recently I've found out that writing assembly on both computers was a thing,
a shame no one ever told me at the time.)

~~~
seanmcdirmid
I went to high school in Mississippi, my sophomore year in 1989 they still had
all-in-one TRS-80s in the computer lab. They were actually good enough for
learning some programming at the time.

~~~
mixmastamyk
Yes, if you had never used a computer it was probably fine, but I was
disappointed I didn't get to learn anything new. Although as a teenager I
appreciated being able to slack off with an easy class.

But again, no one told me assembly language (or C) even existed. Didn't learn
about it until I got to college many years later. Same old 10 PRINT, 20 GOTO
10. Sheesh.

~~~
seanmcdirmid
Well, my first computer was an Osbourne back in 81, and we had an PC XT at
home, so I wasn’t really impressed either. But for most of the kids, even
BASIC was really new to them, not to mention Pascal. I would say those kinds
of barebone computing experiences would even be valuable today, especially
today, no distractions. I’m thinking about getting an 8-bit computer for my
son’s bedroom :).

The teachers knew less than people like us did anyways, I’m not sure what they
could have taught us.

~~~
mixmastamyk
Cool, we do have a R-Pi with a simple Linux distro on it. Fewer, although not
completely zero distractions. Maybe a terminal-only machine has just the right
amount?

> The teachers knew less…

Generally that's the case, but it's possible these were pretty sharp, the
first teacher was _decades_ ahead for example. It was his computer he brought
in. The second teacher, was also my Physics teacher, although I don't have
strong memories in that class.

Just remembered—did ask him why I couldn't copy music from my compact discs to
the computer, since they were digital? And he gave me a "should be
theoretically possible" answer, haha. Many years before multimedia.

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pacman128
This brings back fond memories, it was my first computer. Learned BASIC and
Z-80 assembly on it.

Happy to see it has Level II Basic. Level I was very limited:
[https://en.wikipedia.org/wiki/Level_I_BASIC](https://en.wikipedia.org/wiki/Level_I_BASIC)

~~~
Balanceinfinity
I did as well - until I got my Apple II+ - which was amazing, but didn't have
a built in modem.

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gdubs
That’s one beautiful case. Really impressive documentation too. I have some
Tandy nostalgia: my first computer was a “Sensation” from RadioShack. 486sx
processor that we needed to add an after market math co-processor to for
floating point so I could run Calagari TrueSpace.

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protomyth
The TRS-80 Model 1 was the first computers the local community college had. I
was in HS and my dad was teaching the computer classes. They did earn their
name Trash 80, but they were for the most part good, solid machines. I think
we got them because someone else didn't want them anymore. It would
interesting to find out how learning on those machines affected the students.

(I could go for a modern clone of the Model 100)

[edit: also the parallel (or serial? haven't looked in a while) port switcher
so everyone could print is still in the equipment room, older than many of the
current students]

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xhkkffbf
Anyone cloning the Model 100?

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VikingCoder
Is there a TRS-80 emulator in a browser? Found one:

[http://trsjs.48k.ca/](http://trsjs.48k.ca/)

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codezero
I wonder what the story about the chicken in the image in the middle of the
PDF description is :)

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gadders
Would look much nicer done up as a Dragon 32 :-)

[https://en.wikipedia.org/wiki/Dragon_32/64](https://en.wikipedia.org/wiki/Dragon_32/64)

~~~
jhbadger
That was a 6809 machine that was similar to the later TRS-80 Color Computer
from 1980. The TRS-80 Model 1 was a Z80 based machine released in 1977.

~~~
gadders
I didn't even know there were two versions of the TRS 80 (they weren't very
common in the UK). Thanks for educating me.

~~~
tssva
There were around 6 different incompatible lines of computers sold under the
TRS-80 brand. Within each line there were multiple models with varying degrees
of compatibility with each other.

~~~
ineedasername
Yes, I found that out the hard way when I got a Tandy on clearance with a few
Basic books, and would type out example programs for an hour or so only to
have some of them not work due to some incompatibility. It was probably still
a good learning experience though.

~~~
cr0sh
My first "real computer" (not counting the "computer" in the Milton Bradley
Big Trak - though it was a form of Logo programming, I suppose) was a TRS-80
Color Computer 2 - in 1984.

My parents got it for me after I showed an interest in the Apple IIe computer
that was wheeled around my elementary school at the time (yes - one computer
for the whole school, each teach got it "checked out" once a month - it ended
up being so popular, that the teachers later gave up their break room for the
kids to have a "computer room" to learn in, completely outfitted by Apple and
donations).

Anyhow - I had a TV for a monitor, cassette tape for storage, and a few
cartridges (Canyon Climber and Reactoid were my favorite - though later in my
teenage years I would discover Dungeons of Daggorath).

I typed in tons of BASIC programs from magazines and books, and yes - finding
things incompatible was both frustrating, but informative. I took to learning
how to convert between BASICs - GWBasic, PCjr BASIC, and AppleSoft Basic were
all fairly easy - for the most part - to convert from so as to run on the
Color Computer.

Forget anything for the C=64 or Vic-20, as most of them used tons of POKEs and
the special sprite hardware to get anything done, and were (for a kid)
impossible to understand what was going on or being done.

I also learned how to convert some code from Fortran to BASIC - I had found a
book of graphics code in Fortran, and wanted to run the programs myself...so I
learned.

Later, I found a book that detailed how to convert BASIC programs from one
system to another; that also assisted me. But ultimately, it was a case of
trial and error, tons of reading about the different systems graphics modes,
etc.

I still own all of my old computers; I'll keep 'em until I die, I suppose.

~~~
ineedasername
I wonder if there's a modern equivalent to this discovery process? I mean that
low level systems that require diy and exploration are more thin on the
ground. Even a $35 raspberry pi has layers of abstraction many layers higher,
and the fact that tablets and phones are much more frequently the first
personal computer a kid may own means they don't even need to be exposed to
diy systems like the pi, whereas a few decades ago there was no choice.

Don't get me wrong, access to tech is much better, and that's great. I just
think it's a different experience than in the past. Not necessarily bad,
just... Different

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soegaard
Great write up in the project document!

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gwbas1c
[http://www.glensstuff.com/trs80/trs80.htm](http://www.glensstuff.com/trs80/trs80.htm)
is not secure! Most bargain-basement hosts support https by now.

Egads!

~~~
justin66
THEY are using news of seventies-era computer clones to hack your PC and ruin
your life. You know... them.

