Sinclair ZX80 / ZX81 / Z88 Forums

Hello sinclair users!

My first computer was a sinclair zx81 clone from Brazil back in 1983. It had 2Kb internal memory and later I added the 16K expansion so the computer could be more useable. Back then 16K looked like a lot of memory!

It was a TK82C from Microdigital. Some time later I got a 48K TK90X (spectrum clone) also from Microdigital.

Here are some pics of the TK82C:
http://www.maniadecolecionar.com.br/201 ... -tk80.html

Cheers

Hello Rogério, welcome!

I am also from Brazil and my first computer was also a TK82 and I still have it!

Hi Kelly Murta,

Yes, I know your page, great collection of information and BR software.

I'm trying to recover Demolidor and Marciano to add to the collection, I found them saved in some old tapes. (saw that you already did that, thanks!)

I also have the original tape of Tutor de Matematica and Calendario but stupid me reused the tape to record TK90x programs... I'd love to have these old BR programs back... I haven't find them in other tapes.

My tk82 was sold in 1984 so I could buy an Atari Polyvox. Still regret it, it had the orange box and all....

Cheers,

Hello and welcome to our forum Rogério!



I hope you enjoy this forum

Mark

Hi there! I'm a Brit living in Brazil since late '79. I still have my TK85, but the keyboard membrane died several years ago, and I had to solder in a rewired PC keyboard.

A lot of ZX81 software was copied (without permission), translated and resold on the Brazilian market by local companies. Microdigital marketed software as "Microsoft" until a little company based in Seattle probably sent them a nice letter and they switched the name over to Multisoft. I've been searching out and digitizing what domestic tapes I can find, and a friend of mine is uploading everything I'm recovering to his site here:

https://softwares.oldplayers.com.br/wp/ ... -adaptados

This includes a capture of Tutor de Matematica / Calendário, along with cover, instructions and tape scans, so that might help roo1234.

My university thesis (in 2020) was about controlling a nuclear power plant (or at least an experimental reactor) using a ZX81 (TK85). That was an interesting project. I designed hardware interfaces and hand coded an assembly language program to talk to them. It was intended to be 80 digital outputs, 8 digital inputs and 8 analog inputs to simulate and control valves and display. I wrote the software using the EightyOne emulator and transferred it to tape for loading on the TK85.

Cheers

PS: I was wondering why Simon Holdsworth's site (zxstuff.org.uk) isn't directly acessible from here in Brazil.

Welcome to the club Sam.


Lots to see here in threads various and lots of friendly bods to converse with so feel free to get stuck in as it were.

Love to see the power station gubbins you designed sounds very advanced.

No idea about Simon's site sadly but he is a member (hldswrth) here so perhaps drop him a PM.



Regards.

Moggy.

I'll probably end up being embarassed if I post any more details on the hardware hehehe.

I designed it with 3 x 8255 for digital I/O and a pair of ADC0809 for analog inputs. I made up a plant control panel with anunciators, and had all the outputs running, at least enough to show the university panel.

Here's a pic of the panel... you can just see my TK85 opened up behind it.

As my late father used to say.

"Now that is a bloody thing of service!"

Excellent most excellent.

samscudder wrote: ↑Mon Mar 01, 2021 12:05 am My university thesis (in 2020) was about controlling a nuclear power plant (or at least an experimental reactor) using a ZX81 (TK85). That was an interesting project. I designed hardware interfaces and hand coded an assembly language program to talk to them. It was intended to be 80 digital outputs, 8 digital inputs and 8 analog inputs to simulate and control valves and display. I wrote the software using the EightyOne emulator and transferred it to tape for loading on the TK85.

Hi, is there any chance I could get to see the thesis? I would love to make a video on the topic (channel glasstty on YT). Our son designs reactors for a living and we thought we would look at the ZX81 control option for fun, but then by chance I saw your post. I would be great to see what you managed to achieve.

Hi there,

Welcome to the club!
My first computer was a Tk82c also ... I'm from Rio de Janeiro and have just assembled a clone from scratch

best,
Augusto Baffa