evank

Looks great! I've been looking for inspiration of how to build a simple Donkey Kong, for my Lego arcade machine that I'm starting to build.

Hi everyone, Just wanted to announce that I'm displaying 8-bit Lego Dacta systems at Brickworld Chicago (June) and Brickfair Virginia (August). The focus will be on real hardware: an Apple II, BBC Micro, Commodore 64, and IBM PC, all controlling various Lego machines. For you guys in Europe, the shows in Chicago/Virginia are the two biggest in the US, and definitely worth visiting if you can! Some of you may recall that I previously displayed the life-size Chevy V8 at these shows. My next large model will be a fully playable, 8-bit-controlled Lego Donkey Kong machine.

Wait, I'm way more interested in your four-way interface to use a single 9750 on multiple computers! :) Tell us how you built THAT please. I could use one of those! (I figure it could easily be done by just routing the power wire of four cables into a simple four-way selector switch. But you know waaaaaaay more about electronics than I ever will.) PS. You already have bragging rights, but nobody else entered the contest.

Here's a blooper video. :) https://www.facebook.com/783060741/videos/955264469528726/ PS. I think I said "Thornton". Sorry for botching your name.

A while ago, myself and @Toastie discussed on this forum about how to test Lego 9750 Interface A without a computer. He came up with a method, and I documented it at Brickhacks.com. Now I've made a short video showing how to do it: .... I hope this helps someone!

That's what I figured.

RCX and Micro/Scout used 8-bit CPUs. NXT had a 32-bit CPU. Was there ever a 16-bit version? I'm just curious.

You're insane. :) Then again, I currently have four Interface A running on a single Apple II, and I'm hoping to get a fifth going soon -- I need another card.

@Toastie there were three sets that really jazzed me in my childhood (born '74): 8860 Auto Chassis; 8847 Dragster; and 8858 Engines. I was also blown away by everything in the 8888 Idea Book, especially that program-card crane and that plotter at the end. Non-commercial plug: for anyone else into the 1970s-1980s sets, I have a Facebook group called "Square Pistons". :) https://www.facebook.com/groups/squarepistons

1. It depends. For my life-size Chevy 454 V8 and transmission, I tried to make the engineering as realistic as possible, from the rocker arms to the shifter forks. But for the playable Donkey Kong machine that I'm building, it's going to be entirely custom mechanics that suit my needs, since a real DK machine is electronic and mine is electromechanical. 2. I lean hard to mechanics, while still evoking the look and feel of real things. So mayb 25/75 toward mechanics. 3. 100%. I only build with technical parts of the 1970s-1980s, and these are fully compatible. I don't use anything studless. 4. I like building complicated mechanical models. 5. Stubborness. :) 6. n/a 7. I use both equally. 8. Start small. Build some simple mechanisms. Or copy what others have done, but change some things to make it your own.

Everyone: @LH4PI asked me to post his Interface B power supply schematic on Archive.org. Happy to do it: https://archive.org/details/dacta-control-lab-power-circuit

1947? I was born in 1974. Transpose the least significant digits. :)

Thanks -- I hadn't!

I'm trying to organize my collection of old 4.5V wires. It's easy to cord them up, but then what? Rubber bands? Twist-ties? Something else? I'm open to suggestions.

Does anyone have 1980s Lego Dacta catalogs? If so, then I'm interested in buying/scanning them to share with everyone online.

Just found this thread. The rarest Lego part I own is a prototype of set #9750, "Interface A", which is from 1986. The production units aren't terribly rare, and I have several of those, but a prototype that looks nothing like the original -- and it still works??? I'd love to know if anybody else has one. :)

For sale: all of the hardware you need to control Lego models with an 8-bit computer from the 1980s. For $400 US + shipping, you get the 9570 "Interface A" device; your choice of the 9767 Apple II card or 9771 PC (ISA) card; and a 9700 Technic Control Center kit (lights, motors, optical sensor, touch sensors, and tons of Lego parts). Manuals aren't included, but they are all available free on Archive.org in the "vintage Lego robotics" collection here: https://archive.org/details/vintagelegorobotics. I have two of the Apple II version and four or five of the IBM (ISA) version available. Please send me a private message if you're interested in buying one of the bundles. Or comment in this thread if you have general questions.

I meticulously sort all of my Legos, but never by age. I sort by color/type.

I've already done these things. But the question was, what new Lego parts would we like to see.

I wish they made a 2x2 brick (or plate) with a center pin hole. There's no such part. If you want to stack a 2x2 onto a pin (or to spin around an axle), you're out of luck. There are modified parts, and there are 4x2 versions, but no 2x2.

Welcome to the fun house.

@Toastie, you're correct! I didn't know it, but when I tested your method the other day, there was a 50/50 chance and I happened to have the plug in the right direction. :) On the test port, the top hole is indeed negative and the bottom hole is positive. I will update my write-up. @Carsten Svendsen, I will break part 6 into multiple steps and add more pictures.

I thought it didn't matter. Will do some more experimenting this week.

Which part confused you? PS. I'm planning to make a video.

I can't explain that.