Toastie

Right! I'd be fine, when the poor folks make "only" 1 Million or less per capita and year (no clue how many Kristiansens count towards the family, surely not 1898), but that is another story ... Although I am not that much into pizza, I very much like the approach regarding the question about stickers vs prints. I prefer prints. Best wishes, Thorsten

Well, as said, I did not - this is superb, breathtaking work, YouTube user atkelar has done!!! However, the goals are different, I believe. What he is doing is using 9750 as "simple" (it is simple :D) motor driver. The Arduino Mega does it all. And that's fantastic, but not the goal here, I believe. The whole communication/control is elevated to the Mega. Interrupts for the sensors etc. Totally cool! But the goal "here" ;) is mimicking a vintage computer running original/hacked TCLogo on a (semi) modern machine. And that is rather "different": atkelar transferres 9750 control completely to the Mega. With a >superb< program and approach. You (and now I :D) want to use it essentially to act as a serial2parallel I/O gateway (with no brain), and have TCLogo in control. Is this correct? All the best, Thorsten

Hello Alex, yes! As far as I am aware. And this is on one hand totally easy: Just hack in such a request, and then listen to the port. However, in machine code, these additional instructions may cause terrible things. Absolute jumps will go berserk and so on :D. Nevertheless: Here is a brief summary of all results reported in this thread so far: TCLogo: That requires 9771 (or clone) to listen to address 925 (926) = 0x39D (0x39E) and then act on these I/O ports = full write/read access to 9750. TCLogo_p: This is @alexGS' modified DOS com file 1: Original TCLogo I/O is redirected to a true parallel port responding on 0x378 (out) / 0x379 (in). This is taken care of by TCLogo_p and should run on any "medium-vintage" PC or laptop having a parallel port - and that is the real beauty of it: You can take such a laptop to a "show" or equivalent happening and bring 1986/7/8 4.5V computer controlled LEGO into action, as Alex has nicely demonstrated. TCLogo_s: This is Alex' modified DOS com file 2: Original TCLogo O (so far no I) is redirected to a true OR virtual COM port. So far, I got it to work with TCLogo running within DOSBox_x, USB2Serial adapter declared in the DOSBox_x startup file, connected with a 1:1 serial cable to an Arduino nano equipped with a Serial2TTL adapter, simply listening to what comes in on the serial port: 0x00 = 9750 output 0, 0x01 = output 1 ... and mapping that to 6 outputs/2 inputs using register programming. So far, it did not work on my Toshiba 4090, nor on the IBM XT, BUT I am pretty sure that these 2 beauties want handshake lines to be properly connected; I am just wiring RX, TX, GND. Today that is totally OK (XON/XOFF, and a gazillion of mega Hertz) but back then it was not. Need to make appropriate cables and will report back :D. All the very best and here is to Alex: Thorsten P.S.: Yes, LEGO bricks from 1986 clutch nicely with LEGO bricks from 2023. But LEGO software from 1986 does that as well!!!

Hello Alex, no - I have not seen that - just took a peek - that sounds totally cool!!! Will have to dive deep on this. But even >more< exciting to me: Your TCLogo_s works flawlessly with the Arduino thingy! I mean that Arduino is just a serial to parallel "converter" of lowest level - the program is more of a joke than a "program". However, what makes me a bit happy is that I used strictly the IBM BASIC instructions for 9771 (bit masking and so on) and stayed with sending actually 0x00 (rather than any readable number or the like) for addressing chn_0 on 9750. In other words, the Arduino understands TCLogo addressing. So, I hooked up the Arduino box to the USB2Serial converter on my Win11 64bit laptop, fired up DOSBox_X, ran your TCLogo_s program - and IT WORKS LIKE A CHARM! Your redirection of the original ISA card output to the serial port "COM1" arrives exactly where it is supposed to arrive, and the Arduino happily translates that to 8 parallel bit output and 9750 just does what it is told to do! In summary: Your TCLogo_p works perfectly on 9750 inputs and outputs using a parallel port; your TCLogo_s works perfectly well on outputs using a serial port, regardless of the machine. IBM XT from 1985 or DELL laptop from 2021. THIS IS SO UNBELIEVABLY COOL!!! Thank you so much again for providing these TCLogo variants. Now onto the video you found! All the very best - and thank you for making my day! Thorsten

Oh yes - I am a top expert in screwing things up! This time, all wires I actually soldered were positioned correctly on both terminals. But for some reason, I decided to just not connect 2 wires: Parallel port wires 1 and 14 to 9750 port 1 and 3. Reason? I thought I am super-smart and made a short-cut: As the 9750 output drivers should get their TTL input from the parallel port, any positive supply voltage to 9750 is not required - and the parallel port does not supply +5V VCC anyway. So - hooked up LEDs to the parallel port using 1kOhm resistors - and they all light up correctly when running Alex' TCLogo_p. Which called for another look into the 9750 schematics ... which readily showed that with no VCC supply, no signal will go anywhere as the input (and output pull-ups) optocouplers simply can't light up at all. So added one more line: 1 connected to 14 on the DB25, route through one wire to 1 and 3 on the 9750 terminal. Guess both (Control 0 and 1, corresponding to !Strobe and !Linefeed) are always log1 = high = 5V when not used, as these are inverted lines; off = high. In other words: If I had strictly followed the instructions @alexGS has so nicely written-up, it would have worked on the first try And now my 1998 Toshiba Satellite 4090 runs TCLogo_p Alex has provided flawlessly! Thank you very much again, Alex!!! All the best, Thorsten

Thank you very much - it is a bit of a very niche hobby, I guess. A Sinclair programmable calculator - how nice is that. Just heard of it (Wikipedia), but never had one in my hands. My "programming" attempts began with my Commodore PR100 - 72 keystrokes "memory" ... Getting your old computer up and running again seems to be in reach. Cross my fingers that it works out. Just post here, when you run into trouble; maybe the collective mind can be of help, it certainly helped me >a lot<. All the best, Thorsten

You are very, very welcome! All the best, Thorsten Now that is good to know!!! Thank you very much, @Martin0815!!! Missed that entirely in your post. Cool. My RC train bases seem to be all the old kind. I have thus to use a stepping up/down procedure (lot of IR traffic) in my program. Do you have any idea how to discern one version from the other? Best wishes, Thorsten

Good idea! IKEA's "LACK" shelves (as well as many of their LACK products including tables, cabinets, etc.) are pointing (a bit) into that direction: They appear to be made from 4 cm thick solid material. But they are just hollow structures with rather thin walls, here and there reinforced with 1 cm thick particle board (mostly on the sides). The hollow sections are stabilized with paper folded-up into a honeycomb structure. And as these are basically filled with 95% air, very lightweight but at the same time extremely stable. The moment you want to affix something to these elements, you are essentially restricted to the particle board sections, which is less fun Best of luck with the project, @AD_Bricks! Thorsten

Alright, so this is serious :D Now getting rid of UV, dust, animal's stuff (two cats and one dog living here in the house ;) + no dedicated room = restricts you to "enclosures", right? Best, Thorsten @LegendaryArticuno sorry, was 2 minutes late I guess.

Time for a further update Spoiler first, posting later :D My IBM XT is still very happy: More and more software coming up and running. Most importantly: @alexGS is absolutely ingenious when it comes to old LEGO software. He hacked TCLogo on the 8088 (8086) machine code level and accomplished that 9771 is not required anymore to run TCLogo AT LIGHTSPEED using a (true) parallel port: Very smooth PWM of the 4.5V motors done by the CPU via the ISA bus! He has provided the new TCLogo version on his Brickshelf account. Head over to the first thread mentioned in the spoiler to get the code! And as the IBM is happy, it got a new place in my attic. Had to cut IKEA shelves again - this time 1998 shelves we purchased in the US back then, when I was at UCI. The veneer on these were real wood, about 1 mm thick, beech. And not plastic, as of today ... since there needed to be new supports, I was looking for seasoned "real" beech - and found it in my workshop: The base frame of a large desk, my daughter found on eBay and replaced the frame with steel supports. About 20 years old, that desk is, but in very nice condition. So here we go, the new workspace: Left: 9750, 1090 (Technic Control 1 set), some other 4.5V stuff [4.5V lights from 1092 (Technic Control II), 4.5V battery "box"]; center: IBM XT; right: ZX81, ZX Spectrum; far right: LCD monitor; all "powered up" :D - and hooked up to the monitor with a video switch hiding above the Zeddy [the IBM provides monochrome NTSC on the CGA card's video out; the Spectrum video PAL (with a hack, modulator removed, capacitor added), the 81 NTSC (with another hack, transistor and resistors); the monitor (Telefunken) is so cool - and just deals with the changing signals]. The monitor is in "rest" position - my old chemistry books from back then (1982 onwards) are hiding behind it :D TRUE 8bit multitasking: XT controlling (slowly) 9750 via serial port and Ardunino Nano (serial to parallel conversion; 9750 is readily controlled by 9771 in the XT, but that restricts me currently to TCLogo, working on QBasic using 9771, should be rather straight forward, as in: Yeah dude, straight forward); Speccy running "da trains" via MuLPI :D. Monitor swung into full-action-position. It was a little interesting making the hinges :D. It worked out OK; with the BB Goddard shuttle of NCC-1701-D residing on top of the IBM color display, I feel like ... being in command. Which I am not; these machines do what 8bit machines decide do. And not told to do . Ahh, the teddy bears - left: Got that 1963 from my grandma - and she took care of multiple injuries. He was in Schleswig, Jübek, Kiel, Irvine, Wuppertal and since 2003 Gruiten. Center: My sister made him when I received my PhD degree in 1993. Left: Barely visible: Not a teddy; my sister's interpretation of me when I was around 18 years old ... both have the same travel experience (missing Schleswig and Jübek ;) Rotating disks on 4.5V motors attached to 9750 controlled by the XT. Speccy controlling the trains with MuLPI. The very, very cool prompt of ZX81 - equipped with whopping 16kBytes of RAM! K stands for ... Key? I forgot, tried to Google it - failed. Key-in sounds good. Much more importantly: The Zeddy is happy! Me and photography ... the monitor shows actually a razor-sharp (monochrome) display of the XT's CRT. That is it for the moment. And yes, I move my office chair from time to time to that place - and feel like being 25 again :D All the best, and happy 8bit computing, Thorsten

As there are at least 4 "vintage" IR protocols [RC Car, RC Train, RCX (Scout, Spybotics, NXT w/IR sensor), PF], which one are you referring to? All these 4 do not interfere with each other unless two devices send out light at the same time, which scrambles the individual data streams. But a command or the like encoded by one of the four protocols is only recognized by a receiver using the identical protocol. Shining IR light from the RC train remote does not cause any reaction in e.g. the RC car devices. I am using all of the above in addition to BL and BLE on my layout without any problems. The control program I am using though makes sure that there is only one IR encoded signal at any one time emitted. Best, Thorsten

New as in PoweredUp? Or is there another, newer PF protocol? If that "new" is PUp: That is transported via Bluetooth low energy, which uses 2.4 GHz radio. "old PF" uses modulated infrared light. They will absolutely not interfere with each other. Best, Thorsten

Hello @alexGS, made the parallel cable - but it won't work with my Toshiba 4090 running DOS. TCLogo_p runs fine; it just does not set/read any bits from 9750. I will check that cable ag ain, did it twice, but I am a certified expert in screwing up the pins on any male/female connections. Must be a brain-failure when it comes to mirror images :D Now with regard to TCLogo_s: Here the idea is, that it talks to the serial card/interface, which in turn stores the one byte data in its write buffer and then cranks it out bit by bit, correct? I can hook-up my Arduino to watch the data coming from the PC/Toshiba Laptop ... need to check, what the addresses are that both are using for the serial port. I still can't figure out, how to possibly read back the input lines from 9750. The Arduino can do that rapidly in the program loop. However, it would a) need to be slowed down (no problem) because at 9600 baud (XT) or even higher (Toshiba) it will flood its serial write buffer in no time. That usually holds 64 bytes (and is readily expanded by hacking hardwareserial.h). And b) when TCLogo reads the serial port on the XT/Toshiba, it will read from the input buffer. Well, that is the whole idea of asynchronous communication, I believe. In other words, there is no sync between the data in the read buffer and the time TCLogo accesses that buffer. On the parallel port, this syncing is simply done by pulling down the appropriate IOW/IOR lines etc., which represent a request to write/read data. There is no such thing in serial communication, I believe, other than HW handshaking. But even that would not circumvent the usage of the serial read/write buffer(s). And that is the reason, I am sending a one-byte "read-request" in my QBasic Program: It sends 11000000 to the Arduino (or something > 111111), which then returns exactly one byte with the I/O status of 9750. The QBasic code simply waits during the transmission delay for 1 byte showing up in the serial read buffer and reads it, which empties the buffer. The Arduino is not sending any more data, until the next read request comes. And that slows down things considerably. This represents some (very dumb and very slow) syncing approach, as the read request alone takes up 1 start, 8 data, 1 stop bit @9600 baud to crawl through the serial data line ... Best regards, Thorsten

@Martin0815 and @JopieK: Just FYI: The data encoding, particularly the checksum, is also briefly mentioned here: Chapter "Protocol bit/byte streams encoding" further down, incl. references that I found/used. MuLPI still works; just tested it :D ESP32 code (using Arduino c++/IDE) for MuLPI is available, if anyone is interested, just let me know. Best wishes, Thorsten

And that folks, who never ever touched a LEGO brick before, will securely manage to build the set, because there is one piece (max.) per step in the instructions and all these steps are using color coding, of course. Best, Thorsten

Wow. Is there any budget restriction? An electronics clean room facility may be one route ... dust, animals, and UV gone. Just put the shelves (with no further protection) up as required. Access through a clean room lock only ... I am just kidding But again: What is your targeted cost on this project? All the best, Thorsten

No, it is not. It is a valuable information post! Thank you, Emanuele! Best, Thorsten

Just do it. Honestly. Your calculations are perfect. LEGO bricks, plates, tracks ... are much more relaxed than any calculation tend to predict. Look at that totally illegal #3 bending example (as in: Have fun with it!). Much more importantly: Keep the track elevation such that a train can actually climb it. Nice project! All the best, Thorsten

So am I Emanuele, but you know that I am also glad that this thread does still not implode into the Community ... Hope all is well! Best wishes, Thorsten

But you made me "smiling" about it - maybe a little more than smiling. I know that everything has most probably being said or thought "everywhere" - just imagine the Infinite Improbability Drive - but someone (you) has pointed my nose to it. I am very thankful for that pointing. The original source is wonderful to know, I would have never found it, though. Whoever wrote, sang or performed that song - is ... not that much important (to me). It is deeply and securely put away in my brain. And is readily available. You know, students as well as many more people (of course) not studying Chemistry suffer a lot these days, and maybe, or very probably, since much longer. Thank you again - but let's not derail this thread more than we did. Hmm. On the other hand: I like derailing Sincerely, Thorsten

I'm not alone anymore!!! Well, I have/had quite a few old road baseplates, the green variety. As TLG, smart as they are, changed the layout of these baseplates quite a number of times (to our best of course, and maybe to accommodate the ever-increasing size of their cars, but who knows), and, as I simply had to make decisions - about 15 years ago - area is limited up here in my attic, the greens went "out". Later I needed some low profile 2xalot basestrips (rather than plates ...). You get quite a lot of these strips with that Exact-Zero blade - and the remaining, very smooth and rather thin "road" plate is perfect building material in combination with superglue, the gel variety. No, I am not a purist. Gave that up about ... 20 years ago. When I tried it the first time, I had Johnny Mandel's song running in the back - first because I love it, and second because I thought something very bad will happen, when I cut this piece of ABS ... actually it was worse: "cutting and hollowing out" ... Be rest assured: NOTHING happened! It just went through. And after hollowing out, I had an almost "perfect" 2x4 LEGO ABS "frame" in my hands. Yellow and true (old) dark gray, not the bluish stuff. Encouraged by this totally illegal "technique", I took out the road plates. Looked very carefully, closed my eyes, selected the Exact Zero Sword and ... The sword of time will pierce our skins It doesn't hurt when it begins But as it works its way on in The pain grows stronger, watch it grin No - pain - at - all! A little sanding with (German scale) 800 whatever paper - and - I had the first 2x32 base strip of this universe in my hands. I felt like being in Billund - creating new pieces, the world really needs. Wait, here it is: . @Murdoch17 Exact Zero blade - that made my day! Thank you! All the best, and yes, don't take any of this seriously: I am a chemist. Thorsten

Agreed. The IBM PC was "invented" in the US though; as were Apple computers ... and they say in that 20th anniversary video, @Coder Shah (thank you!) has posted, that an estimated 30% of the schools in the US had one or more of these sets back then. So could it be that the kids were already playing in Europe with C64's and 9750 (all you need is a cable + the LEGO Lines program), while in the US, it was a little later with Apples and PCs? And in that video they were addressing the US folks rather than - well - amateurs playing with C64 gaming machines? Best, Thorsten

I agree with all others: Very nice MOD. Equally important: Very nice and clever use of available resources! From YouTube, BL, Stud.io to bricks'n'plates! All the best, Thorsten

Ahh - same "trick" with the ZX81 I guess - the Z80 was mostly busy with redrawing the screen ... counting up to 100 takes half a minute or more (have to check, just got that one up and running again. In fast mode, the screen is gone, and the CPU is doing what a CPU is supposed to do; swapping registers and jumping around Best, Thorsten