Sinclair ZX81 Made Out of Lego 97
Posted
by
samzenpus
from the blast-from-the-past dept.
from the blast-from-the-past dept.
An anonymous reader writes "I used Lego's Digital Designer software to build a model of a Sinclair ZX81 — the computer that kicked me off on my interest in such matters way back in 1981. Until very recently, the software allowed you to upload your model, buy it and get a boxed set with all the pieces to build it (as well as instructions). The ZX81 model is as close to the shape of the original as I could make it, considering that Lego is quite a lo-resolution modelling tool. I even made it so that you can lift off the lid and see a representation of the PCB in side. I have also posted the model to Lego's Cuusoo site — a place where you can post ideas, and if they gain enough support they will be considered for production."
This is kinda neat (Score:4, Interesting)
I used to own one of these. I soldered it together out of a kit when I was 11, with some help from my dad. I accidentally left the soldering iron against part of the case though, so there was a neatly melted hole there. :-)
When we added the 16k RAM pack, we discovered that the power supply was stretched to its limit providing the current for all that. So he designed a new case out of wood and aluminum and also reverse-engineered the keyboard hookup and got a keyboard with actual moving keys from a local electronics parts shop. Unfortunately, there is now something wrong with how the tape jack is grounded, and it can't record on tape anymore. :-(
I still have it though, 30 years later. The first computer I ever owned. I even have the sheets I made up collecting machine instructions by addressing mode (since they were listed by number in the manual) to make it easier to write machine language programs for it. I wrote my own binary multiplier since the ZX-80 chip doesn't have a multiply instruction.
This lego thing is vaguely interesting. It's neat to see the familiar shape again. :-)
Re:Why would anyone care about this? (Score:5, Interesting)
I must be the only one in the world excited by this - Only because it taught me about the existance of the Lego Digital Designer - and it runs in wine!