Toastie

Oh - that is interesting! Now, you can do that as well by importing a "plate within a brick" from MLCAD into Studio - but then the parts become transparent, at least with the (maybe stupid preference) settings on my computer. Also, they would not render - and this is what I am using Studio for: Adding flexible parts (ingenious solution here - as with flex-track in the Bluebrick software) and rendering. When things are not perfectly lining up upon import, these are missing in the render. Sometimes wiggling them around a bit works, sometimes not. Is there a setting in Studio to tolerate (tiny) misalignment? That would be cool. All the best Thorsten

Yes! Here we go: It is a nice find though!!! The topic has been discussed here quite a bit. But: Thank you for the link (I did not have it!) All the best Thorsten

Hmmm, Math seems to be all good. But then: You said "CAN connect this in real life" ... Real life always has ... lovely ... "margins". A computer needs to be told to tolerate these. Does Studio do that? I don't believe so, but I may be wrong. Experienced the same thing many times, when importing from MLCAD (LDraw) into Studio. OK, MLCAD lets you do what you want, even having a plate positioned within a brick (which is of course nonsense, but ...). Studio is smart, but not living in a real world. It is annoying, but it is what it is. Good luck on your project! All the best, Thorsten

Oh for sure! My Crocodile is commanded around by an ESP32 clone That was not exactly the point: Just imagine you want to build something and motorize it. And besides building skills you have acquired serious knowledge in many other areas but C++ programming, BLE hardware and so on. In other words: You need to use what TLG offers ... Best Thorsten

Oh yes. As with all software based platforms. In the beginning, the possibilities seem to be unlimited - but eventually the hardware trails further and further behind ... software/firmware all evolves further and further - and then: Pull the plug, say "sorry to have to inform you" or something in that direction, make something new. I really also agree with the total failure of keeping the LWP3.0 protocol documentation where it was, when the faulty initial version was published. But then: They need to sell new stuff. Time doesn't wait for them, it keeps on rolling ... lets find out the hard way, what the lifetime of LPW3.0 and PUp hardware will be. Best Thorsten

I am sorry - just because a board has colors I recognize as "Ardunio" certainly does not make them Arduino! Wow. It is really cool, what you have accomplished! And absolutely: Let us enjoy LEGO jointly! All the very best and have a nice day, Thorsten

Very good reasoning, as far as I am concerned. Best Thorsten

So ... just learned that a retro computer work/place/space makes it to the front page! (it is an Apple, isn't it?) - This is soo so cool Well, here we go - this is even beamed back in time a little further than Apple 2E ... As I am working on a ZX Spectrum talking to the LEGO serial tower (with reply ... sigh(!)) - it seemed to be appropriate to "prepare". And as said elsewhere, I got both, my ZX81 and my ZX Spectrum from 1983/85 back to work. Before diving into old electronics and old and current programming - I prepared myself creating the right environment to work on this (during endless nights ): There is the Zeddie on the left, with the 16k MonsterRAMPack, and nifty 9V power supply. On the right front is the small scale LEGO version - as it was, last millennium: The Zeddie, the cassette player for true mass storage, power supply, couple of mass storage cassettes, CRT (that one I got from my mum - was a red "Colani type" CRT - no edges, just curves. For me, it was quite the challenge to build that one with bricks, see below. Back right is my laptop showing a Stud.io render of the scene. Back left is the "CRT" = LED TV I am using as ZX display. This needs some modding to the ZX81 video output, as around 1980, VHF/UHF was the standard. Today, hardly any TV set knows anything about RF - at minimum they want composite video. In front of the TV is a good quality audio capturing device, used for loading/saving Zeddie programs from my laptop (almost "glitchless" when using Audacity). Credits for the LEGO models: The Zeddie LEGO model is based on Steven Reid's design: https://www.reids4fun.com/. I just replaced the round 1x1 tiles with square ones. And made some space for the cables. Also resized the RAM pack a bit to fit the scale and moved it a little to the right - as in the "original". The cassettes - I can't find the reference anymore. Merde. It is >not< my design. The CRT is; however, the front screen idea is not. This is from http://www.fubiz.net/2014/04/30/retro-technology-lego-kits/retro-technology-lego-kits3/. I just changed the direction of the curved slopes and the scale. BTW: The Zeddie never produced a decent picture back then with the RF modulator - so this is why the screen is not grey/white only. I believe the cassette player is also my design - at this scale. The lid actually opens, and you can insert one of the cassettes - see LDraw MPD file. The LDraw MPD file is here: https://brickshelf.com/cgi-bin/gallery.cgi?f=582185. This BrickShelf folder is not moderated yet though. I believe this is it. As my photography is crappy, here are some Stud.io renders. (Shadows below the devices because I am too dumb to get the wires bent in a way they don't penetrate through the floor - and Stud.io does adjust the floor location to the lowest part - as far as I know. The cassette player ... right now it plays a program to be loaded into the ZX81 - may take several times though! The "Colani type" CRT I had back then, back view. Black = power, yellow = antenna in ... And here is the Zeddie: The Zeddie with RAM pack. Sorry for just the renders; but as said: I am not good with photography. All the best, Thorsten

... oh yes and the CRT looks like being of some age - I love it. Wonderful!!! OK, and all the Arduino stuff - brilliant! Wow. Congratulations on the front page - and more so on your design! All the best Thorsten

Good evening Jo, wow, what a nice find!!! This makes things much clearer!!! Thanks a million. The diagram is to the point. This is the new reference then. Best wishes, Thorsten BTW: Found a really cool code (IMHO) for generating 38kHz on an Arduino (works well on Uno R3 clone, pin 11): void setup() { pinMode (3, OUTPUT); // Just to switch ON/OFF pinMode (11, OUTPUT); // Pin 11: Timer 2 "A" output: OC2A // set up Timer 2 TCCR2A = _BV (COM2A0) | _BV(WGM21); // CTC, toggle OC2A on Compare Match TCCR2B = _BV (CS20); // No prescaler OCR2A = 208; // Original value: 209. // Original comment: "compare A register value (210 * clock speed) // = 13.125 nS , so frequency is 1 / (2 * 13.125) = 38095" // This results in 37.83 kHz on the Uno R3 clone board // Changed to 208 - this results in 38.01 kHz } // end of setup Copied from: https://forum.arduino.cc/index.php?topic=102430.0 I hooked-up an IR LED (or just plain vis LED) with cathode to pin 3, anode via 1kOhm to pin 11. Running the sketch on pin 11 38kHz/50% duty cycle is always present. Pin 3 is just to turn the LED on/off. Using any of the SoftSerial libraries allows you to modulate the Baud rate on the LED 38kHz emission. The thing is: That code does not interfere with any of your loop code. Best Thorsten

@JintaiZ Very good idea. Title now better? Thanks a lot! Thorsten

Dear All, after I was sleeping two days over opening a thread on "an idea", I am just doing it: This thread is intended to be a (Mindful) Pub to discuss ideas/projects/wild thinking/just memories/the good ol'days/8 bit/crazy16bit/express printers printing NCC1701/PDP10/11 ... and mostly 8bit computers - controlling LEGO 4.5V/9V/12V/RC/PF/ and yes: PUp devices. Whatever comes to mind. 8bit computers are OLD. Very old. As in: You may think the chemist down the road is old, but that's just peanuts to the age of 8bit computers. We are talking true retro here. C64, Dragon 32, Oric-1, BBC Micro, ZX's, Amstrad CPCs and so on and so forth. I don't know why, but it just never "left" me. When I was 23 years old, my wife (I was studying - well - chemistry) allowed me to buy a Sinclair ZX Spectrum. And it all began. Games never ever interested me (other than cracking the "copy protection" using the disassembled machine code) - it was the hardware. And changing/adding things. Controlling periphery. I graduated with a degree in chemistry though - and all figured out is "true homebrew". It was the world of TTL, CMOS, and ECL ... and the world of 16k x 1bit chips being expensive. Just imagine: The 16k ZX Spectrum I had was ready to be upgraded to 48k. There was also a factory version of the 48k Spectrum. To make that one as cheap as possible, Sinclair used defective 64k x 1bit chips: These chips are organized in 2 banks of 32k. Upon final testing manufacturers as TI and others sold chips with one defective bank to other companies as "32k" chips. Can you believe that? Yes of course. It makes total sense! But today? Never ever. Now, the idea for this thread is: Can we control ancient or even current LEGO electronics with 8bit computers? I am working on: Let a ZX Spectrum talk to an RCX brick. Why? Because. Nothing else. It has remotely to do with LEGO bricks being around since the 1960s - and still clutching - and LEGO electronics officially appearing and disappearing even faster than fashion trends do. You may think: So what. He has the ZX IF1 featuring an RS232 port. Well. The ZX speaks (hardwired = bolted in) 1 start, 8 data, no parity, 1 stop bit. The RCX speaks (again: Hardwired into the UART) 1 start, 8 data, odd parity, 1 stop bit (Challenge 1: Parity change). And then: The LEGO IR serial tower cranks out and sucks in bytes with no protocol at blistering 2400 Baud. The ZX IF1 can't handle that: After receiving 1 byte is pulls down the CTS -> RTS line - allowing one more byte and then think about how to store that (Challenge 2: HW protocol - the tower is totally dumb). Possible solution: Arduino as translator. We'll see. This thread will not be heavily populated, I believe. And it will take time. We are talking 1980s. There are some folks here on EB though who may have something to say ... or maybe not. @dr_spock suggested the title of this thread @Duq repairs old washing machines @zephyr1934 knows how to print NCC1701 on endless paper @UltraViolet likes when an EB topic is derailed because of 8bit computing ... This is it. Don't expect a viral thread. I am old. The cool thing though is: Posting here after ... let's say a year or so of silence will not get the moderators mad, as it is designed to be a repository All the best, Thorsten P.S.: Just for those who were born 2000(+) : k stands for kilo. A 16k x 1 RAM is a chip that holds 16384 bit (0/1). You needed 8 to get 16kByte RAM. Today, a 16G x 8bit DDR3 DIMM module, which holds about 1 million times more bytes, sells for about the same price as 16kByte cost in 1982. In other words: 1 bit then was 1.000.000 times more expensive than 1 bit is now, 40 years later.

So folks, how about open up a thread in lets say the "Mindstorms and Robotics Forum" on vintage computing and LEGO? I am still on it. The ZX Interface 1 is now under investigation here. Documentation is rather scarce. I hooked up the LEGO serial tower - so far sending things to the tower is straight forward: The Speccy just kicks out the bytes one after the other with no delay when setting hardware handshake lines appropriately (and man, the names they give to the DB9 pins are in a total mess. As are the mic and ear jackets. It is mostly "inverse", as if they wanted to tell us: The Zeddy MIC socket connects to the MIC input of a tape recorder ... etc). So the tower sends what it gets. Problem #1: Odd parity required for RCX communication. The Speccy can't do that; baud-rate flexible, one start, 8 data, 1 stop, no parity - over and out. Problem #2: The "buffer" length when reading data back from the tower is: 2 bytes. And then it thinks a bit and then tells the connected device to shut up until done. Took some time to figure that out using an oscilloscope but: Done. Well the tower though is totally dumb; it just sends out what it received. No handshake at all. Idea: Use and Arduino. Get an RS232 shield ($5) with the MAX232 pins providing RXD, TXD, RTS, CTS for communication with the Zeddy. Get another one just using RXD/TXD for the tower side. And a bit of software to do the translation. Oh well. We'll see. Best Thorsten @dr_spock: When I was typing, your reply came in - full duplex here. Yes, let us do that! @zephyr1934: Nice! I was taught how to punch holes into a card, feed that to a PDP10 "cluster" of three to have them print out "hello world" on an express printer in the computing department. That was fun.

And this clearly says: It is built with LEGOs. Because sometimes I simply forget that your creations are built in LEGO space. I believe, it gives a very nice, clearly discernible "touch" to your perfect creations. Otherwise, it would be just that: Perfect. But that is ... well ... perfect. LEGO is LEGO due to its limitations. And you push these limitations to unbelievable small size. Very nice model. I love it. Best Thorsten

This. Thinking along the same lines. With regard to PU: And still be rather secretive about the PU firmware - the LPF3.0 protocol information was outdated TLG released it. Best Thorsten

I changed my mind on this issue after building the "Flying Dutchman" form MouldKing. I have not seriously searched for the original builder/company ... it sounded like a product from them. So if that one is a rip off then I do apologize In any case, for me, it is a real flagship - with very original ideas and building techniques not found in LEGO models (maybe as they are too unstable during the building process but in the end turn out rather nice). And very nice unique parts as well. I'm still 90% with TLG, but I like to look around and make up my mind. If we were as purist with everything else in our life as we are with LEGO bricks and TLG, China would certainly not be the #1 exporter in the world. Best Thorsten

That is the best part of it! Cheers!!! (Oh - then my second brick career started 1997. It was a DUPLO ambulance for my daughter - but when browsing the shelves I was simply taken away ... far far away. And then came Mindstorms RIS. It hit me hard 1998 at Target in the US (me and my family lived there for some years) - and that was it: No life without LEGO anymore. It was a very good experience and decision. My first set was 323 ... Did remove the funny lines. All the best! Thorsten @Jesete Sorry I can't reply in Spanish - but my goodness, Google translator has pretty much improved. So yes: What you are saying is what I am saying. I believe Best Thorsten

You are right (of course ) - they are stackable. But in a "restricted"/limited way: You can stack the dark gray terminals as you wish (PF connectivity on the top and the bottom side of the terminal), so one power source can feed as many power consumers as you see fit. That is true for the PF receivers as well as for dumb PF motors, lights etc; these PF power consumers have a dark gray terminal as well. Also here you can stack them to heaven as well, i.e. stack x PF motors to one power feed, either a PF battery box or PF extension cable, light gray terminal, top side. The extension cables have one dark gray and one light gray terminal. The latter has full PF connectivity on the top but "only" 9V connectivity at the bottom. And the 9V terminals connect to the C1 C2 lines of the PF circuitry and not the 9V GND PF lines. So without a little DIY there is no chance - as far as I know - to get battery boxes in parallel (nor in series). I can't remember whether the short (20 cm) PF extension cables (8886) had two dark gray terminals - I cut all my short PF cables for custom purposes - but again, one terminal PF/PF the other PF (upper) 9V lower, for sure. It is a secure way of preventing kids or purists of building a 1kV power supply or 9V one which can be used for welding - provided funds are available. But hey, there are enough 9V block battery (the PP3 size types) videos on YouTube, where they stack them in series - up to hundreds of them ... worthwhile to watch The really cool thing though is: These PF extension cables are preventing power source stacking - and at the same time provide PF <-> 9V conversion. TLG could have ditched the latter (simply no electrical contacts at the bottom) but they haven't. Again: I believe all that. I just work here. Just saw your post above has changed quite a bit - all has been said there, so sorry for all the long text up there. But maybe others are interested, maybe not ... BTW: I collect LEGO since 1965 - well it was less than "collecting" more "getting". But lived through 4.5V, 9V, 12V, PF, PuP. Oh yes 9V - the best time of my LEGO life ... which explains maybe why my PF motors all have either pin headers or sockets or 9V terminals Best, Thorsten

Why am I not surprised? Very nice of you Emanuele! Have a nice day, best wishes Thorsten

Which changes quite a bit with load on a motor of course. A stalled PF XL motor draws 1.8A (https://www.philohome.com/motors/motorcomp.htm) whereas with no load it draws 80mA at 220 rpm. No surprise here, this is what happens to E and B fields when you don't let them do what they want. And yes, when there is over-current protection in the battery box, nothing much will happen, as this one will kick in as soon as TLGs decision, what over-current means, is reached. Now, as we are reading here about 9V - PF conversion cables, custom wiring, etc., all of which I have done extensively (30 PF/Technic motor driven switch points wired up with LEGO wires = dramatically negative budget, which the higher authorities in this household never pass! So: Go cheap = DIY). The old battery boxes don't have any electronics in them. And then lets say we start out with fresh alkaline batteries. When you put these in parallel, V = const = 9 V (ideally of course), but A(max) = 2x. At least this is what I have learned back in the days, and here it is from a vendor (which does not mean at all it is correct, of course!): https://www.digikey.de/en/blog/series-and-parallel-battery-circuits. Going back to the alkaline batteries: They can easily provide 1A (not for a long time :-) and with only 1V https://rightbattery.com/118-1-5v-aa-duracell-alkaline-battery-tests/ ) so a stalled PF XL motor hooked up to unprotected 2x9V battery boxes in parallel may well produce 2x6Vx2A = >20W in heat. That of course will not happen, as at every electrical connection, which has only a slightly elevated resistance, the plastic material around it may have hot times. And yes, when the charge state of the batteries is different, the first deal which each other quite a bit and when peace has been announced, the leftover is available for fun. As least this is what I make of it - but you know what? I just work here Best Thorsten

Yes. Fully agree. It is getting pretty much closer. It may be off-topic as it is non-Technic - built the Flying Dutchman from MK recently. Man. That was a blast. True modeling. No playability. Just beauty. She sits here - and nothing TLG ever made comes even remotely close. Of course, as far as I am concerned. And yes, I am still a 90% TLG only "follower". 10% are gone because of the FD experience. Complaining is one (lame) thing. Constructive criticism is another. And careful wording a third. If I were in charge at TLG, I would always read all the complaints and criticism, regardless of wording: Learning and learning. TLG is successful. So you can just shrug it off or ignore any of the complaints etc., live in your own bubble of success - or you can take these as input for future decisions. I bet they do the latter without telling much about it. 60 years of success ... no other way, as far as I am concerned. Best Thorsten

As I see some nice interest here: Whenever possible, go for the RCX1.0. Not the 1.5, not the 2.0. What happened is that they just(!) reduced the electronic piece count on the 1.5 and 2.0 bricks as hardware improvement (for them). As far as I can tell - I run these bricks since 1998. The 1.0 brick has this "DC in socket" ... you can feed it with anything between 9 and 15 V DC or AC. Which means you can run them off a wall wart - for ever. When your creation is designed to function autonomously and without power cable, just unplug it after programming and testing - it then goes to battery operation without glitch. And vice versa. The 1.5 and 2.0 sets provided also improved firmwares. Which all run flawlessly on the 1.0 bricks as well. There is absolutely no difference. I have had them all - but gave away the 1.5 and 2.0 bricks to folks wanted to have them - for free of course. The 2.0 firmware is available out there. Best Thorsten Confirmed, you really can. You may want to be careful hooking up the PF L and XL motors, as the H-bridge drivers in the RCX bricks can't handle such a load for a long time. You will notice power drop-outs. The PF M motors work really well on the RCX, even under serious load. Best Thorsten

This depends. In principle, you are absolutely right. Things may change though when it comes to increasing load. A stalled XL PF motor draws serious amperage when the source allows that. So without a PF receiver in between, current may reach unhealthy numbers. With receiver that one will max out, as they are overload protected. So in the end, with two batteries in parallel, one receiver controlling power (and this limiting current), it is as you said: Doubling the run time. Best Thorsten

Dear Old Soldering Iron Enthusiasts (OSIEs), I just digged out my RCX IR tower, opened the documents and checked twice - just to make sure that I did not write stupid things coming just from memory. It appears as if all is OK so far in my previous post. Just to round things off - here are a couple of more things (none of which are essential): You can operate the LEGO IR serial tower with just three lines: RXD, TXD, GND when using e.g. a terminal program like HTerm to check things out or run your own programs off from an Arduino or the like. Sending bytes to the tower triggers the internal mono-flop, which in turn awakens the TSOP1738 IR receiver, as you can see in Marc Bellis' circuit diagram shown here: http://www.mientki.ruhosting.nl/data_www/lego_knex/lego_electronica/ir_tower/ir_tower.html As long as the LED on the tower is on, you can monitor incoming data from the tower. After that time it goes to bed again and nothing comes through. Now, sending e.g. CR or LF or Null repeatedly every 3 seconds or so to the tower keeps it alive, and you can continuously monitor the IR traffic in the room. All this does not apply for your home-brew IR serial devices, which can be as simple as IR LED + 38 kHz modulator and TSOPXXX38 as receiver. LEGO software sometimes wants to see the RTS CTS bridge but that does not do anything to the serial traffic protocol. And finally: The original serial cable that came with the RIS1.0 set flips RXD and TXD. To get a RS232 plug into the tower you need to use a rather "slim" plug. Always in for something special, these TLG engineers Best Thorsten

Yes, that one works. Well it is even far "easier" for those who still like soldering irons: All you need is a 38kHz modulated IR diode and one of the 3pin 38 kHz IR receivers (there are so many, I use the TSOP 34838 - runs on 3.3V, is smaller than TSOP1738 and very reliable - and dead cheap). That's basically it. For the 38kHz on/off modulation you may use an Arduino (then you can also use the remaining computing power to fly to the moon); a CMOS/TTL NAND (as they use in the tower) oscillator works nicely as well, or use the smallest 6 or 8 pin PIC from the microchip line (or any other vendor). All you need to do is convert the signal on the TX line of the serial port to 38kHz IR light - and detect 38kHz light on the RX line. Bit protocol is a bit odd: 2400 baud, 1 start-, 8 data-, 1 stop-bit, odd parity. Here is some more and nicely organized background info (just in case). http://www.johnholbrook.us/RCX_guide.html http://www.mralligator.com/rcx/ Also: Get a USB to serial converter that provides full hardware control pinout; the IR tower itself does not do >anything< of that sort but simply bridges pin 8 (RTS) and 7 (CTS) of the serial port. Some LEGO and other software looks for that signal to detect whether the tower is present; it is a bit frustrating when looking at the circuit diagram of the tower you find no hint of flow control at all, but the thing you made yourself seems not to work simply because that bridge is not there - or your USB converter cannot imagine that some folks still do hardware handshake stuff. Here is all you need plus a couple of hardware examples: http://www.mientki.ruhosting.nl/data_www/lego_knex/lego_electronica/ir_tower/ir_tower.html Have fun! Best Thorsten P.S.: Just forgot: Yes, the IR detector picks up the IR light from the diode because there is no flow control at all. LEGO called it "echo" back in the days. When you want to be very smart (as I wanted to be) and electronically block that echo, some LEGO software does not work anymore, as this "echo" tells the program "a properly working tower is connected".