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Microbaud MLDL anyone .. ? - Printable Version

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Microbaud MLDL anyone .. ? - ThomasF - 12-02-2020 07:01 AM

Hi,

Years ago (many) I bought a MLDL box, developed M-Code etc for the 41 and even modified it by adding more memory to it. Smile

I recently found the box amongst my other old 41 stuff, but I can't get it to work anymore.

The PCB itself is marked "(c) Microbaud Developments Machine Language Interface '82 HP-41", and on the backside it says "(c) 1982 Microbaud Developments", "ML I VER. A" and "Made in Aust", and if I remember correctly I bought it directly from Australia back then.


This MLDL is probably very close to the original by Lynn Wilkins, so I might be able to reverse-engineer the PCB - but is there anyone out there who might have a copy of the schematics for this version of MLDL?
Googeling has not given me any clues about the card (apart from a similar question on this forum back in 2004 with no responses), but any scans of some schematichs might help!

Best regards,
Thomas

RE: Microbaud MLDL anyone .. ? - Sylvain Cote - 12-02-2020 12:32 PM

Lynn A. Wilkins MLDL article and schemas was published in PPC Journal V9 N3 P27@35.
You can get the journals from Jake Schwartz (PAHHC) at http://www.pahhc.org/ppccdrom.htm

RE: Microbaud MLDL anyone .. ? - ThomasF - 12-02-2020 01:15 PM

Hi Sylvain!

Yes, still got all PPC journals so getting schematics for the original Wilkins MLDL is no problem Smile
I was hopeing someone still got the documentation/schematics for this Microbaud MLDL board.
But, I'll probably have to go into "reverse engineer" mode and redraw it from scratch using Wilkins as a base line - hopefully they are not that different ... Wink

Cheers,
Thomas

RE: Microbaud MLDL anyone .. ? - Sylvain Cote - 12-02-2020 02:16 PM

(12-02-2020 07:01 AM)ThomasF Wrote:  but is there anyone out there who might have a copy of the schematics for this version of MLDL?
(12-02-2020 01:15 PM)ThomasF Wrote:  I was hopeing someone still got the documentation/schematics for this Microbaud MLDL board.
Hello Thomas,
Oups! I had not read your initial post correctly, sorry.
Sylvain

RE: Microbaud MLDL anyone .. ? - ThomasF - 12-08-2020 01:11 PM

A bit embarrassing as my search was not good enough.
I just found the documents I was looking for where I should have searched in the first place!
So now I'm ready to dig into the MLDL-box again Smile

RE: Microbaud MLDL anyone .. ? - KimH - 12-08-2020 01:29 PM

I built my MLDL based on an Australian diagram (I have a copy in Pencil from back then) after having waited for them to send me a PCB (I had paid 50 AU$ for it, but it never arrived).
Maybe they were connected with MicroBaud. Would you be OK to share what you got, curious Smile

(12-08-2020 01:11 PM)ThomasF Wrote:  A bit embarrassing as my search was not good enough.
I just found the documents I was looking for where I should have searched in the first place!
So now I'm ready to dig into the MLDL-box again Smile


RE: Microbaud MLDL anyone .. ? - rprosperi - 12-08-2020 01:29 PM

(12-08-2020 01:11 PM)ThomasF Wrote:  A bit embarrassing as my search was not good enough.
I just found the documents I was looking for where I should have searched in the first place!
So now I'm ready to dig into the MLDL-box again Smile

Worry not, it's not only you. I often find misplaced things in the exact same spot! There can be no doubt that some of these things quietly migrate when we're not looking... Smile

RE: Microbaud MLDL anyone .. ? - ThomasF - 12-08-2020 02:27 PM

(12-08-2020 01:29 PM)KimH Wrote:  I built my MLDL based on an Australian diagram (I have a copy in Pencil from back then) after having waited for them to send me a PCB (I had paid 50 AU$ for it, but it never arrived).
Maybe they were connected with MicroBaud. Would you be OK to share what you got, curious Smile

Hi Kim!
Search on TOS with "Microbaud" and you will find what I was looking for ... Smile
/Thomas

RE: Microbaud MLDL anyone .. ? - KimH - 12-08-2020 03:08 PM

(12-08-2020 02:27 PM)ThomasF Wrote:  
(12-08-2020 01:29 PM)KimH Wrote:  I built my MLDL based on an Australian diagram (I have a copy in Pencil from back then) after having waited for them to send me a PCB (I had paid 50 AU$ for it, but it never arrived).
Maybe they were connected with MicroBaud. Would you be OK to share what you got, curious Smile

Hi Kim!
Search on TOS with "Microbaud" and you will find what I was looking for ... Smile
/Thomas

Thanks Thomas, that was exactly what I had in pencil. Built mine with "Fädel" a German version of WireWrap.

Now here is some fun for a couple of hours reading and taking a walk on Memory Lane

/KimH

RE: Microbaud MLDL anyone .. ? - ThomasF - 12-27-2020 05:14 PM

YES!!

35+ years later I picked up my modified MLDL-box, and with some new soldering, debugging and rewireing I managed to bring it back to life again! All RAM is still working!

Alas - there is no PC-connection - and have left my eprom-burner somewhere a long time ago - but still!
First step will be to write some small functions and refresh my MCode skills ... Big Grin

At least this year ends slighly positive ... Wink