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@LH4PI Just to make sure the cable is correct here's diagram.  It can be very confusing when male and female plugs are used.  It took me hours to wrap my head around it when I was using cat5 serial adapters.  Very useful for long runs or in my case I had an old POS terminal with RJ50 serial ports.  If the cable is correct there could be another problem.

vzLvq

 

 

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Thank You all . I  should test once more using only 5-5 ,3-2 anf 2-3!

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5 hours ago, BatteryPoweredBricks said:

@LH4PI Just to make sure the cable is correct here's diagram.  It can be very confusing when male and female plugs are used.  It took me hours to wrap my head around it when I was using cat5 serial adapters.  Very useful for long runs or in my case I had an old POS terminal with RJ50 serial ports.  If the cable is correct there could be another problem.

vzLvq

 

 

Very easy to remember

RS232 connections....
Regular Soldering 2 to 3 and 3 to 2
(but I'm older and used comuters like PDP11/24 etc)

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Hi  again 

 

I  check with my multimeter and find an cable  in my archive that exactly was configured as    Battery PoweredBricks  picture  shown    and tested once more  the connection between  computer and interface B (9751 (070909)) .

 

No luck ! . I have to dismantle the thing to see what   circuity that is broken .  To my knowledge  nobody  have  so far dismantled and documented the inside of  interface B  on this forum  so I may be the first !

 

-----------------------------------------------------------------------------------------

 

I also look at my  archive back  in the beginnings of 1990 when my  children was small  and find  a lot of stuff that I have forgotten.:

I am owner of a  full documentation of Dacta  9701  manuals   (including  Dacta  9701-1,2,3,4,6,7 (9701-5 is missing)  as most parts  of the Legoset of  9701  including  the mentioned 9751 (that I have to fix !!) .  May this manuals and  building instructions  are of  any value for the Vintage Lego Robotics  archive ?. I also are the owner of the  1992 yers old  "Equipment for Primary Schools, Pre-School and Special Education " from Dacta  44 page  info that covers from education material  from "Early Years to Special Education" in fact describe in the end interface A applications .

I also have the  most parts and documentation  including camera for the  Vision Command constructopedia  9731  ,  including  but not test software for the Windows 98 and XP  but may be this is   counted as Mindstorms products  and threfore not of interst here to collect.

 

Finally I also find  the  50 page catalog for the  "Lego Technic Control Center " 8485   including the hardware  as well as a 5 language  (DK,S,FIN,D,China)  14 page  user manual how to use the  Lego Technic Control Center  to manually program it from 1995.

I played  with the Lego Technic Control Center just recently and it is very intuitive  and a great way to  learn to program in a very basic  way  without a computer "

 

As I understod I can not  attach files  since I am  not allowed  to upload more than 0.04MB since I am still a "New Member"

By the way,  I also have two NXT Mindstorms packages and was programming in in Labview(robolab)  and use it as a prototype platform  professionally at R&D department   in my earler work :

 

Now  I have other focus  and I want to see if I can  get the Robolab  working together with   interface B  if i can it fixed  and tested the original software  on my existing computer (see earlier photo)   and then running  vintage computer (Windows 98 or XP, so if anybody still run that ,please contact me .

So if this material  can be of any use  for other in this group , you know I have it .

 

Sorry for the long message  but  it was fun  to look back at my existing  material and  thinking  what remarkable  things Lego made  in  for education area    already  30 years back ! 

 

Best Regards 

Lars Herrnsdorf

 

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Hi Thorsten and BPB,

 

I try to find info  before I start to try to fix  my broken  interface B:

Maybe you remember   the following:

Scanning  this forum  I found that  at least Thorsten got pictures  from an Italien guy that seem not to  be on the forum anymore of the inside of the interface B  and even  found info about the  ucontroller  used : (SAB 80515/SAB 80C515
8-Bit Single-Chip Microcontroller ).  the info was from  from 2020  discussed  in the train forum  but the links  to the pictures no more is  active . It looks like photos was taken   describing the  contents of the board . Do any of you have this pictures still  handy  to send me ?

my mail is lars.herrnsdorf@gmail.com

 

Best

Lars

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@LH4PI I think I've only had a problem with one of my interfaces not communicating, IIRC I just set it to the side and used another I had.  So I really don't have much to add to the conversation for fixing the issue.  One thing you can try is a test program (LEGOInterfaceB.exe) written by Tom Cook.  It will work on modern operating systems (I've tested up to Windows 10) so you can try on another PC just to see if it works.  Beyond that I'm really not sure what else to try

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Hi Lars (@LH4PI),

could you provide that link, where this Italian guy is mentioned? The search function of EB is not of much help to me in this case ...

I don't own an interface B - but before you go diving into the innards of the IB electronics, particularly the Siemens SAB 80515 chip ... in 95% of all my RS232 "troubles", it was the serial port/cable wiring. I did not really look into the details yet, but are you sure that the 2/3 crossing and 5 (GND) straight through (5/5) is all there is? Could very well be, but true null modem cables also cross 4/6 and 7/8 (for 9 pin hardware handshake). LEGO was always creative and did some tricks to make you use their very cables, as others did not work.

@BatteryPoweredBricks: Is the 2/3 crossing the only thing happening in that cable? It does not mean anything should there be more wires used, but, well it could be. TLG did something nasty it on the totally dumb Mindstorms IR tower as well; this one only uses 2/3/5 for all functionality, but without a 7/8 bridge within the tower, the original LEGO software refused to work.

All the best,
Thorsten   

   

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Thanks  BPB  I try to document my  finding !

Hi Thorsten 

I fully agree that in almost all cases the serial cable wiring is the source of communication error   That's why ask several times in this forum for exact confirmation and BPB has confirmed that in deed only three wire was used  to 3 pair of pins . I should check up the link again to the Italy guy!

 

All the best Lars 

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Hi Thorsten 

Here is what you write ( I searched on" SAB 80515"  to find your comments  about a picture , do you still have it ?)

--------------

;

  On 6/25/2020 at 8:51 PM, GianCann said:
https://www.bricksandchips.it/2020/06/25/linterno-del-control-lab-9751/

Now this is what I call decent electronics. This is so nice and clean.

How much did you pay? I know, BL is our friend.

Best
Thorsten

 

----------------------

Best/Lars 

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7 minutes ago, Toastie said:

 

@BatteryPoweredBricks: Is the 2/3 crossing the only thing happening in that cable? It does not mean anything should there be more wires used, but, well it could be. TLG did something nasty it on the totally dumb Mindstorms IR tower as well; this one only uses 2/3/5 for all functionality, but without a 7/8 bridge within the tower, the original LEGO software refused to work.

All the best,
Thorsten   

   

In my testing 2, 3 and 5 were the only wires necessary.  I'll include a video where I went through the troubleshooting of the RS232 connection (starting at 23:17).  They were the only wires connected.
 

 

Update on my non-functioning unit:

One of my units refuses to connect to the official Lego software as well as 3rd party.  It kept giving the same error over and over again (I think it just said unable to connect).  I figured it wouldn't hurt to replace both capacitors (220uf and 2200uf) since they are so old.  Now it just gives a checksum error.  Not really sure where to go from here.  I vaguely remember leaving one of my control labs on for several days controlling the lights on my Galaxy Explorer display but I can't remember if this was the unit.  Also there is a bit of rust / corrosion on some of the screws and a couple places on the board.  I didn't even notice at first it was so minor. 

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Fantastic LegoROBOLAB !!I

Exactly what I have hoped  to find !, I have translated the pdf  it to Swedish  and now I can clearly see from the pictures   how easy the  front and the circuit board  can be separated . By the way ,do you own yourself this  interface ?

I should first look for old tantale capacitor that is a big error source  on this 31 old card , already have to de solder  the 220 uF 35 V  one on the 9V power supply board that  was short circuited , so I have now 9V , but no communication , maybe  this capacitor is vital also for the serial  communication to work so I have to test with a new one . Nevertheless now i can start  digging in the problem and hopefully the    SAB 80515 chip is intact !

 

Thanks  again 

All the best Lars 

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Hi Thorsten

I have not yet  been able to  test that  since the external power supply (a small  card  near the 9 pin serial connector  do not include  a 5 V regulator  so it must be on the main board . By the way  how  do I attached  pictures , i only have  40 Kbyte allowance .

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39 minutes ago, LH4PI said:

i only have  40 Kbyte allowance

Hi Lars,

you need to use an image host platform (e.g. bricksafe etc.) for storage and then c/p or embed the image links into your messages.

Best,
Thorsten

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Hi  Thorsten et .al.

I now have  started to  found  the   problem with the "faulty"  serial connection  for my 70909

 So far I have  mounted two 100uF 16V tanthal capacitor  in serial (all I have )  instead of the 220uF  35V  that was  bad .   Maybe it is not enough to make the voltage stable  ( only used two rectifier diodes now around 14 V with 2V ripple ). I found  that  this Voltage is used as input to create the for  5V on the main board used for the SAB 80515. 

 

I  found how the   small power card  was working  and could make the schematics for it .  I can confirm that also  pin 4 is connected  in the cable  up to the main board (put I do not know if it is actually sensed by the microprocessor).   as well as  pin 5, 2 and 3 in the serial interface  as well as  GND  ,a stable 9 V and  a unregulated 12V  DC for the main board .

 

On the main board  so far   I found that  the  5 V as well  as the oscillator 12Mhz   its okay . 

 

I put my  USB oscilloscope  directly on the  RxD pin pin  21 on the microcontoller Siemens SAB 80515  and  decode the message :

As You can see from the image  taken it is something  electrical wrong with the first part of the  pulse train (voltage levels is not correct ) so the micro controller have no chance to  read correct  the  send  string .

 

It should be "p\0     ###Do you byte, when I knock?$$$"     but as you can see from the image and the decoding of the pulse train  the  first characters is missing due  to the poor  pulse waveform  in the beginning  ;

only  from "u byte, when I knock?$$$"  can be read , so of course  the  controller program can not  initiate  correctly . 

 

Hopefully it is nothing wrong with the Micro controller  and as soon  I can get pulse train into the  computer serial port it should  "start up"     finger crossed 

My next  step is to control how I can fix the initial  pulse train ( more stable  voltage supply, more faulty capacitor on the main board , bad shielding ?  ) and  also test  with  desktop PC  that normally has with better  ground and more stable Voltages  for the serial  port interface  if that could be the problem  since  now the laptop I use is battery operated and the battery is poor  due to 30 Years old battery so I run it on power supply that introduce a a lot of   noise from the power line (can not easily be grounded)  .

I keep you informed and if  anybody have any suggestion related  to my finding so far  please  tell 

 

 

All the Best 

Lars

 

send70909serialcodecorruptinthebeginning.png.723a4495dd3042c670e576a51d7599c8.png

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57 minutes ago, LH4PI said:

I  found how the   small power card  was working  and could make the schematics for it

Hi Lars,

can you share that schematic as well?

For sure the UART in the SAB chip gets confused with the serial input, but I would not know how to trace that to a faulty power board without knowing how that is wired.

What is the primary power supply you are using? Should the ripple etc. a problem: Do you by any chance have a stabilized 12V DC power supply, let's say around 1A? That would remove all ripple, and the diodes take care of polarity issues. However, first it would be good to have a look (sketch is enough!) at the power delivery section (the small board) before making any further suggestions.

Best,
Thorsten

 

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Hi Thorsten 

Success!

I change the computer from  the 30 year old laptop to an old  mains powered  desktop  XP Pro  Sp3  that have two serial ports on  and  now using Com1  interface  and "correct voltage levels with a standard UART  in the XP"  the 970909  interface works directly  with the  BrickLab.exe  that I have handy . I test all outputs  and varied output levels and directions  and I am almost sure  everything work, but I have to  mount  together the box to verify .  I should now look for a usb to serial  dongle  for further test  on another old HP XP  laptop that I have .

as soon I get the  bricksafe  account  approved I can start to  send images . I have to spend some time  to make a nice schematics of my drawings before  it is readable !

 

Best Regards

Lars

 

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17 minutes ago, LH4PI said:

Success!

Congratulations!

That is very good news! I actually believe that you can use a Win11 computer with such a dongle and a terminal program for starters! Also, the VS C# program, Tom is providing on his website (https://lgauge.com/article.php?article=technic/articles/LEGOInterfaceB) should work!

Very cool - I love it.

All the best,
Thorsten

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Hi Thorsten 

Thank You, Thank You 

I couldn'r resist   already verified that the same program also worked on a Win 11 computer using Aten UB to RS-232 adapter  model no UC232A 

The driver installed sutomatically . Have to change the serial port number from port 7 to port 1 in the system manager . I could hook up a few sensors/motors and could  verify that all inputs/ outputs works!

 

Now I should install original Dacta software on my Laptop running windows using this usb/serial dongle !

All the best/ Lars 

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22 minutes ago, LH4PI said:

running windows using this usb/serial dongle !

Woo-hoo!!! :pir-love:

OK, getting sentimental - but: One of the things that drive me, is getting "good old" and "apparently new" stuff together. And the serial port (now in the incarnation of USB) is the way to literally talk to - ancient teletypes, in a decent way. Or the very first computers. I love the original handshake approach, the original serial interface implementation (25 wires ...). You know that 2 + GND wire (+ XON/XOFF in software) is just a matter of hardware speed, but essentially same old thing: When you are busy, I won't talk. And vice versa.

And now you have the LEGO Interface B at your fingertips! Simply wonderful.

Have all the fun with it! Or: Ready Player One!

All the best,
Thorsten 

Edited by Toastie

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Yes , fully agree, It is something with the RS 232 world ! . When you get it to work  You almost sense how  the hardware  and software , work together.  

 

I have still a lot of tools that uses serial ports , a lot of HP 95, 100 and 200lx palmtops  with a wonderful terminal  program (actually,I have to try to run the original lego data software on this Dos platform if I can find a mouse that can run from the IRDA interface that this small palmtops has  besides the RS 232 port and PCCARD slot )  , two German made ISEL made 4-axes cnc milling machines,  a dispenser unit,  voltmeter,  oscilloscop and now Lego interface B all about 30 Years old and still going strong !

 

Have heard about .an Irda controlled mouse with driver for 3 1 DOS ?

Best Lars 

Edited by LH4PI

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50 minutes ago, LH4PI said:

all about 30 Years old and still going strong

And that is a blast!

I recently "returned" to my beloved Sinclair ZX81 and Spectrum, the latter having a RS232 port - they all live here in my attic - along with a PCW8512 (Joyce), an IBM XT and an Atari 1040 - all from around or before 1985 - almost 40 years old (next year is going to be THE big celebration data party up here - OK me, a bottle of Captain Morgan, and the other oldtimers) - and all going strong, as you said. And talking happily to my Win11 laptop. 9600 baud - the >real< light speed and true benchmark in serial data transfer world ...

You should dive into LEGO Interface A world - some here on EB know much more about than I do! That is so cool; 1986 LEGO Technic ... controlled by either of one of the above oldtimers - or a Win11 laptop. Sooo cool.

Have fun!

All the best,
Thorsten

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Hi  Good news today  for me for the use of Dacta original control Lab  .

 

I found  the original  docking station to my  HP Omnibook 600C  and using that serial port  I could  get the serial transmission to work  running windows 95 version on my  windows 98  computer . I have run the software and program the graphical  interface  without any errors for several hours so  the software /hardware is stable :classic:

 

I almost get the same  software  working on another computer  Running windows XP pro using an ATEN USB to serial dongle  , I could read inputs and control motors  but only for  a short time  but the software get transmission errors that you could delete , but soon you get the same error  message again . Using bricklab.exe   the communication  works without problem .  So I can confirm taht other has said that  the Dacta control lab  win95 version  do not work on  XP (but almost) 

 

Now I should the  my other Omnibook 600C that  have windows 3.1  installed and see if I can  that  computer to run  Dacta  control lab win 3.1 version !

 

Best/Lars

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