The Mindful Pub - A Discussion Thread on 8bit Computers and LEGO

[dr_spock]

I still have a copy of IBM DOS 3.10 copyrighted 1985. 128K RAM recommended. Back when a Bill dude said you didn't need more than 640K of RAM.

I finally picked up that freebie SCOUT. It had issues with leaked alkaline batteries.  I guess Duracells.

Took apart to clean.

Replaced the broken negative terminal with a spring

Threw some Dyson power at it. 

It can run my PF motors with a PF extension cable. What else can it do?  What software is used to program the SCOUT?  I don't have a serial IR tower.

 

 

 

[DrJB]

What an inspiring/refreshing thread! Read it all and enjoyed it (Loved the youtube video with all the 'Lego computers evolution'). Glad to see I'm not the only 'technology hoarder' on here. I don't go that far back in history, but I love it when simple things do work, and are easy to debug. Yes, none of those systems compares with the EV3 self balancing robot, but the visuals and how everything works is refreshing. Keep up the good work, some of us are following (and very curious).

Edited November 13, 2022 by DrJB

[Toastie]

On 11/2/2022 at 5:10 AM, dr_spock said:

What software is used to program the SCOUT?  I don't have a serial IR tower.

Then you should get one - they are very handy. Serial tower, make your RS232 cable or get an original (all that sells dead cheap on e.g. BL), plug into decent serial2USB adapter, install Bricxcc (on your Win 7/8/10/11 machine) and off you go. Make sure that the COM port of the serial2USB adapter is <9 otherwise, Bricxcc will not find it.

Alternatively, you can use the SCOUT SDK files and then use TLCs ideas of running code (I don't like that much, but it is OK). Also, the SDK comes with nifty trouble shooting stuff.

Let me know (PM or here) if I can be of any further help. I have all the original TLG software as well as Bricxcc running on my Win11 laptop.

Very nice work on the SCOUT!!! It is a wonderful machine. I love it.

 

On 11/2/2022 at 5:10 AM, dr_spock said:

I still have a copy of IBM DOS 3.10 copyrighted 1985.

These are sooo nice. I love the looks.

I am making rather good progress on my IBM XT. After a rough start (apparently dead motherboard - sigh), and a VERY steep learning curve, I managed to have this beauty boot-up from a GoTek flashed with the newest FlashFloppy firmware. This GoTek thing behaves now as 720k Tandon 100 2a floppy drive (there are two in the XT) - the only difference is that it holds up to 999 720k disk images on a USB stick ... time goes by, so slowly.

I need to do some cosmetic changes, and will then post here ... still working on a 1988 Seagate 30MByte RLL drive I found in the basement as well, but that one may be dead. Did a lube job with opened lid (so lost warranty :D - too bad) to inspect and manually move the head assembly. It came back to some life (i.e. looking desperately for boot files, but without success) but remains silent after a while. We'll see :D

All the best,
Thorsten

 

Edited November 13, 2022 by Toastie

[DrJB]

The Scout is the predecessor to the RCX, and as such, fair to assume they work essentially the same?

 

     

 

How about THESE scouts (I have 5+2 ... lol), are they programmable at all and useful for other functions than intended? ? They have built-in light and touch sensors.

 

Edited November 16, 2022 by DrJB

[Toastie]

7 hours ago, DrJB said:

The Scout is the predecessor to the RCX, and as such, fair to assume they work essentially the same?

In principle, they do; the Scout has only 396 bytes of usable RAM though - the RCX is a 6kB memory monster :D. There are other subtle differences, as one can't change the firmware on the Scout (as far as I know) - I guess because it has many built-in functions and procedures as well as hardware: the SCOUT features a light sensor and the third motor output is hardwired to an LED, which is modulated with TLGs visible light link protocol (VLL) motor commands for operating the motor on the MircoScout (bottom right). You can also let the MicroScout run some "scripts" which are also programmed using VLL. The Spybotics on the bottom left brick is again programmable using NQC - it speaks essentially the same language as the RCX and Scout, with lots of extra commands and functions for inter-brick communication, sound, light effects. The Spybots need the Spybot com cable (IR/VIS link) for programming - it resembles the tower for the RCX and Scout.

The USB tower (center) does "not work" with Win64 OS - there is "no" available driver out there. It does work on Win32 machines. There is also a procedure for building the 64bit driver using National Instruments software, however, it was too much for me, as there seem to be also legal issues using this software for building the driver, but I don't really know. I gave up on that. The RS233 tower works nicely with a RS232-USB adapter, so that is OK, at least for me.

Spoiler

You can also generate all the communication signals yourself and use e.g. the serial tower and an VIS LED to control them all; almost all the information is out there, I just put things together here:
https://www.eurobricks.com/forum/index.php?/forums/topic/188584-mulpi-a-multiple-lego-remote-protocol-interface/

Best wishes,
Thorsten

 

[DrJB]

Thank You for such valuable information. You obviously have spent quite a bit of time investigating such devices. *Cheers*

[Toastie]

40 minutes ago, DrJB said:

You obviously have spent quite a bit of time investigating such devices

True - more than 20 years . It all began in 1998 when I was using QBASIC on my Toshiba Win98 laptop to operate my brand new RCX independently of the RIS1.0 software, which I found a bit strange, as I actually learned (FORTRAN) "programming" on a PDP10 at the University of Kiel/Germany. Actually, I found and still find hardware much more interesting. This has changed since SMD not only took over, but became so small that soldering with my iron became essentially impossible (for me).

Solution: Stay with the old stuff. 1980 - 1990 is great. Adding here and there some current hardware as protocol translators ...

All the best,
Thorsten

[BrickTronic]

On 11/2/2022 at 5:10 AM, dr_spock said:

...

...

Hello,

Is it possinle to make closeup pictures from the Scout PCB Assembly Top & Bottom View ?

Jo

 

[dr_spock]

On 11/13/2022 at 5:47 PM, Toastie said:

Then you should get one - they are very handy. Serial tower, make your RS232 cable or get an original (all that sells dead cheap on e.g. BL), plug into decent serial2USB adapter, install Bricxcc (on your Win 7/8/10/11 machine) and off you go. Make sure that the COM port of the serial2USB adapter is <9 otherwise, Bricxcc will not find it.

Alternatively, you can use the SCOUT SDK files and then use TLCs ideas of running code (I don't like that much, but it is OK). Also, the SDK comes with nifty trouble shooting stuff.

Let me know (PM or here) if I can be of any further help. I have all the original TLG software as well as Bricxcc running on my Win11 laptop.

Very nice work on the SCOUT!!! It is a wonderful machine. I love it.

 

These are sooo nice. I love the looks.

I am making rather good progress on my IBM XT. After a rough start (apparently dead motherboard - sigh), and a VERY steep learning curve, I managed to have this beauty boot-up from a GoTek flashed with the newest FlashFloppy firmware. This GoTek thing behaves now as 720k Tandon 100 2a floppy drive (there are two in the XT) - the only difference is that it holds up to 999 720k disk images on a USB stick ... time goes by, so slowly.

I need to do some cosmetic changes, and will then post here ... still working on a 1988 Seagate 30MByte RLL drive I found in the basement as well, but that one may be dead. Did a lube job with opened lid (so lost warranty :D - too bad) to inspect and manually move the head assembly. It came back to some life (i.e. looking desperately for boot files, but without success) but remains silent after a while. We'll see :D

All the best,
Thorsten

 

Thanks. I should check with my LUG to see if anyone wants to part with their IR tower.  Maybe it can be made using an Arduino Leonardo with IR LED and IR receiver?  I found a copy of the Scout SDK and Scout Tools.  I have an IBM Thinkpad T20 with Windows 98.  Love those old IBM laptops that you can easily swap out the hard drives with different OS on them.

Cool, it's alive. I thought the IBM PC XT came with 5.25" 360K floppy drive. Do you need an .img file of the IBM DOS boot diskette?  Old hard drive magnets make good fridge magnets.  :-)

 

On 11/14/2022 at 12:41 PM, BrickTronic said:

Hello,

Is it possinle to make closeup pictures from the Scout PCB Assembly Top & Bottom View ?

Jo

 

I can only get the top view.  The circuit board negative contact pad is so corroded that I had to solder the battery negative terminal to what tiny bit of copper left on the PCB. The PCB is no longer removeable to get to the bottom side.

[DrJB]

Those 8 white squares look like RGB LEDs??? ... didn't think they had them back then.

[Toastie]

On 11/14/2022 at 6:41 PM, BrickTronic said:

s it possinle to make closeup pictures from the Scout PCB Assembly Top & Bottom View ?

Here's the bottom view of the PCB - nothing much to see - other than corrosion :D Did the same thing as @dr_spock, but had enough non-corroded copper on the top side to solder connections there so that I could still use the metal strips (after heavy treatment) and thus batteries:

 

Best,
Thorsten

Edited November 16, 2022 by Toastie

[Toastie]

20 hours ago, dr_spock said:

I thought the IBM PC XT came with 5.25" 360K floppy drive. Do you need an .img file of the IBM DOS boot diskette?

Yes it did! And both are doing fine. The thing is that when starting at ground zero ("OK, I have a dead XT from 1985, so what do I do now?"), with no DS DD (and not HD) 5 1/4" floppies anywhere to be found in my personal universe, I began to look around. eBay was inspiring, but most of that stuff comes from the US: Item $40, delivery $60+ and so on. After replacing the main board with a clone from 1986 ($120, from the EU) the seller thankfully also made a 5 1/4" floppy boot disk for me. So I had 1 boot disk for DOS 3.3. Turned out it was only the 8088 CPU that died on the original main board ... And yes, I damaged that floppy (so I thought) as the XT refused to boot up after some time madly tinkering with all the hardware ...

Many, many nightly "hours" later (YouTube, and most importantly here: https://www.minuszerodegrees.net/), I tried the floppy disc drive on my Win98/DOS6.2 laptop from back then, which did not freak out to format a 720k(!) 3 1/2" floppy - and the XT can handle such a drive when a corresponding floppy is inserted. Believe it or not, I found such a drive in the university "basement", well there were many ;) Next was making a boot disk ... as the 3 1/2" floppy drives were happily talking to the XT; format b: /s made a bootable 3 1/2" DOS3.3 floppy.

However ... I don't like to change the front of the XT to accommodate a 3 1/2" floppy drive ... it looks - wrong.

Well, then I found myriads of images of old software on the internet - and then discovered the "GoTek". Chinese made, dead cheap. Ultimately powerful microcontrollers on board, they make e.g. old CNC (and others, you name it) machines come alive again; all you need is an image (and they are out there), a USB thumb drive holding up-to 999 images, and replace the old floppy drive in that machine with the GoTek. It is amazing.

My XT now boots off from the GoTek - and I can do that over and over again - even when booting, turning off the power does not do any harm.

So what I currently do is: Get this XT up to full operation. Use the GoTek to do the hard work. And then revert to the 2 floppy drives - in the meantime, I purchased 10 blank 720k DS DD 5 1/4" floppies for 20 bucks.

So it evolves. The latest was downloading the Landmark Diagnostic images and test the system as much as I can on a clone main board - which is mostly restricted to peripherals, as this software expects the original IBM ROM chips.

And most importantly: All this is to control all my LEGO trains (RCX, RC, PF, PUp) from the XT, as I did with my Spectrum.

Best,
Thorsten

[BrickTronic]

On 11/16/2022 at 8:24 PM, Toastie said:

...

Hello

Many Thanks to @Toastie and @dr_spock'

Big surprice, that uC seems to be placed under the LCD


Jo

[Toastie]

Hello Jo,

now, if it is important to you, I can remove the LCD from a "broken" SCOUT and take a shot.

You probably know this website as well: https://brickipedia.fandom.com/wiki/Mindstorms_RCX#Scout

At least we learn it is a Motorola microcontroller with so-and-so much RAM/ROM.

Just let me know.

Best,
Thorsten

[BrickTronic]

5 hours ago, Toastie said:

Hello Jo,

now, if it is important to you, I can remove the LCD from a "broken" SCOUT and take a shot.

You probably know this website as well: https://brickipedia.fandom.com/wiki/Mindstorms_RCX#Scout

At least we learn it is a Motorola microcontroller with so-and-so much RAM/ROM.

Just let me know.

Best,
Thorsten

Hello Toastie,

Thaks for your proposal, I'll be happy to get more Details here.
The Bricjpedia-Page mentiones a Toshiba uC with 32k (Mask-) ROM and 1K RAM
Would be nice to figure out what Processor exactly and maybe to find its Data-Sheet
I'm asking myself, if there is also an LCD Controller used like in the RCX

Jo

[Toastie]

Lill' update ...

Regarding my new brand new IBM XT (5160, IBM color monitor, 2 x 5 1/4" Tandon DS DD floppy drives) - as said before, I really don't want to alter the front of the XT to an extent, that it does not match anymore with my memory ;)

That means, that a GoTek case, somewhat compatible with a 3 1/2" floppy drive, should not show up at the "front" - it would ruin my memory :D

So I made a fake ISA version of the GoTek with goes into one of the ISA slots. No electrical connections; just snug fit. The white plastic material mimicking the ISA connector is from a IKEA shelf system, the metal pieces are from a cut up expansion port slot cover ...

The idea is that the GoTek can be fired up any time I want to use a 360k or 720k image downloaded from the net and then copied (in case of 360) to a 5 1/4" floppy.

There is one more thing to solve: It is hard to operate the GoTek on the back. So ... some soldering and wiring to an attachable front OLED panel with some buttons is in the works - using LEGO bricks ... we'll see.

 

 

Best,
Thorsten

 

 

Edited November 18, 2022 by Toastie

[Toastie]

On 11/16/2022 at 1:36 AM, dr_spock said:

Maybe it can be made using an Arduino Leonardo with IR LED and IR receiver?

It can be made with an Uno ... let me know what you need - I believe I have some Arduino routines here.

Best,
Thorsten

[Toastie]

Hi @BrickTronic,

On 11/18/2022 at 8:14 PM, BrickTronic said:

I'll be happy to get more Details here.

Here you go:

and even closer:

 

This document (PDF) may be a matching datasheet - it is from Toshiba, from 1999, it covers 8-bit microcontrollers, and it has an onboard LCD driver. But who knows, TLG is always making big secrets about their electronic chippies: 

https://brickshelf.com/gallery/ThorstenB/ThisAndThat/SCOUT/tmp86cm29u.txt

(You need to rename the .txt extension to .pdf - Brickshelf does not like PDFs to be uploaded).

Best regards,
Thorsten

 

[dr_spock]

On 11/16/2022 at 12:24 AM, DrJB said:

Those 8 white squares look like RGB LEDs??? ... didn't think they had them back then.

I think they might be single color surface mounted LEDs.  I haven't seen them changed colors in the short time I played with the Scout.

 

On 11/18/2022 at 4:35 PM, Toastie said:

So I made a fake ISA version of the GoTek with goes into one of the ISA slots. No electrical connections; just snug fit. The white plastic material mimicking the ISA connector is from a IKEA shelf system, the metal pieces are from a cut up expansion port slot cover ...

Nice work.  A long, long time ago I mounted a Commodore 64 300 baud modem to a slot cover after converting it to work on a PC for friend.  I used a slot cover that already had a cutout for a DB25 connector.

 

On 11/18/2022 at 5:38 PM, Toastie said:

It can be made with an Uno ... let me know what you need - I believe I have some Arduino routines here.

Best,
Thorsten

I have a UNO too.  What routines do you have? 

[Toastie]

7 hours ago, dr_spock said:

I have a UNO too

Just trying to find my stuff ... I believe to play too much with all sorts of vintage things. Once I have reanimated old electronics, I seem to lose interest just to find more vintage electronics :D

To make sure: You want to "mimic" the RS232 IR LEGO tower, is this correct? And the software you are going to get in touch with the SCOUT is TLG's SCOUT SDK and/or NQC or the like, is that also correct? I am asking, because some programs of the SCOUT SDK are testing the waters, i.e. check if there is a serial tower attached or not. And lastly: You want to operate "your IR tower" from an USB port or from an RS232 port?

Best,
Thorsten

 

 

 

[dr_spock]

Good questions. I guess mimic RS232 IR LEGO Tower. I have a RS232 port on my old Thinkpad. I ran ScoutTool.exe in Windows 98. It's looking for ghosts?  

I received an order of MAX232 chips today. Going to turn an old Minitel into a serial TTY terminal for the 3D printer. They might be useful for a RS232 tower too? All this old hardware is a slippery slope, eh?

Thanks.

[Toastie]

On 11/22/2022 at 5:16 AM, dr_spock said:

I ran ScoutTool.exe in Windows 98. It's looking for ghosts?

Oh yes - TLG and names ... very camouflage they always are ... This is from the Scout tool help PDF:

Note: The Scout Tool includes an alpha version of LEGO's new communications driver called "Ghost" (which will replace "Spirit.OCX" for products released in the future)

BTW, there were never any updates of that alpha version within the Scout SDK - software development sucks :D. Well, the alpha version works fine. However, the Mindstorms SDK 2.5 (this is a really nice package!!!) has all the documentation needed to use the GhostAPI (data transport protocol, good for the C/C++ hardcore programmers almost hacking the PCB :D) and the IVPBrick COM interface (for slackers like me, who use VB6 and the like ...).

Yes, there was a time, back then, when Y2K appeared to be a deadly threat, and TLG produced detailed and very nice to read documentation of their software products! 

But back to your RS232 tower:

In this case (mimic the tower), the UNO is a bit overkill, but will work of course!!! It would also come in very handy, if you e.g. wanted to tap into the data stream from/to the computer to the PBrick or generate byte codes, wrap them into the IR protocol and send them/listen to a PBrick. As the UNO runs on 5V; you would need a MAX232 or the like anyway. All the UNO would then do is generating the 38KHz modulation of the IR LED light, preferentially using one of its timers, so it does not suck up any memory:

// Program 38kHzOutput (fixed pin 11)
// Code copied from:
// https://forum.arduino.cc/index.php?topic=102430.0
// How to create a 38 Khz pulse with arduino using timer or PWM?
// Used here with no changes on an Uno R3 clone

void setup() {
 pinMode (10, OUTPUT);               // Just to switch IR LED ON/OFF; used for RS232 data stream
 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

void loop() { 
  //digitalWrite(10, HIGH);   
  digitalWrite(10, !digitalRead(10));// toggle; LED cathode is connected to pin 10
  delay(1000);                       // wait 1s
                                     // LED anode is connected to pin 11 via a 220Ohm resitor
}

 

As you have ordered the MAX232's this will work for sure - and the nice thing is you have the UNO as power supply!

The serial tower is as dumb as it gets :D. Here is the schematic, I copied from this website (there are others as well, but they are not entirely correct):
https://robotika.sk/maine.php, but I can't find the drawing on that site anymore, did copy it last year or so:

Here is a thread on EB, which shows a non-UNO approach (the UNO replaces everything in the above schematic but the IR LED(s) + resistors + TSOP):

Just see the OP entry, as you don't want to go wireless.

Most importantly: When using TLG software (Scout Tool etc.) make sure that the bridge 7-8 (RTS-CTS) is present. The software probes that line.

Let me know if you need anything else. BTW: All the LEGO software runs fine on Win11/64bit with a USB/serial converter. The latter just needs to be on one of the first 8 COM ports, as no one thought back then there will be more than 8 COM ports on any computer to come in the future :D)

Best,
Thorsten

 

 

Edited November 23, 2022 by Toastie

[Toastie]

5 hours ago, dr_spock said:

an old Minitel

What a beauty!!! Just read the Wikipedia article about Minitel/Télétel - I had never heard of this before, thank you!

From that article: "It downlinked at 1200 bit/s (9 KB/min) and uplinked at 75 bit/s (0.6 KB/min). This allowed fast downloads, for the time." It is always good to recalibrate from time to time ... fast downloads :D

How come that you have a "QWERTY" layout on your Minitel?

This is a very nice project! A Minitel telling a 3D printer what to do ... I wonder what people would have said back then to 3D printing

Oh yes, it is a very slippery slope. And fun to ride it!

Best,
Thorsten 

[dr_spock]

16 hours ago, Toastie said:

Oh yes - TLG and names ... very camouflage they always are ... This is from the Scout tool help PDF:

....

Thank you very much for the snippet of code and links.  The RTS-CTS is good to know. 

 

14 hours ago, Toastie said:

What a beauty!!! Just read the Wikipedia article about Minitel/Télétel - I had never heard of this before, thank you!

How come that you have a "QWERTY" layout on your Minitel?

...

I have a "North America" version of the Minitel.  The keyboard feels pretty chiclet-key.  It was used in a Bell Canada service called ALEX.  It has a DIN 6 RS232 port in the back.  I think it could be used as a serial monitor for the Arduino boards too.  Maybe display messages from a Mindstorms EV3 with a bluetooth to RS232 interface?

[Toastie]

Oh my ...

... just put "everything" together, after >serious< cleansing of "everything" that my IBM XT (5160) consists of - plus retrofitted the GoTek as ISA module - plus an OLED display, an LED, three micro switches, all mounted into a LEGO brick-built display, that fits into the slot of one of the two Tandon 5 1/4" drives as removable fake floppy .

Before I learned about floppy images, how to make and use them [FlashFloppy (https://github.com/keirf/flashfloppy), HxC (https://hxc2001.com/), and ImDisk (https://sourceforge.net/projects/imdisk-toolkit/) software].

So then it was time to copy my old stuff still residing on my 1998 Toshiba 4080 laptop - back then I had one RCX, and always wanted to control more than one - as I envisioned to have RCX PBricks operating LEGO trains (on the engines). Made a 720k image containing QBasic1.1, my program files (and command.com ) for the GoTek, which talks flawlessly with the IBM XT floppy controller (that one can read 720k floppies, but not write or format them).

So booted into DOS3.3, ran QBasic1.1, loaded my "PBCon.BAS" program ... 

... and then I got this:

Sorry for the bad image quality, but NTSC is NTSC ... here is a screen close-up:

Wow, I even made a revision history string variable; February 6, 2001 ... and then I pressed F5 (run):

>Never< expected to see this on an IBM XT from 1985 running code from 2001 in the year 2022.

Need to check the serial connection - diagnosis said, that card is OK ...

Will post the IBM XT restoration and GoTek upgrade here as well. I know that hardly anyone is interested in such stuff, but it was fun to get it all going. And I used some LEGO bricks to get it done ;)

Best wishes,
Thorsten