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Posted By: rfka01

MUPID C2A2 - 04/19/17 09:13 PM

This is an Austrian BTX (i.e. Videotex / Prestel) device that doubles as a home computer ... if you download the software via BTX grin

[Linked Image]

This archive contains photos of the mainboard, dumps of the ROMs and a manual ... unfortunately this is for the C2A2's predecessor, the original MUPID.


Here is information about the machine in English:


Some other interesting pages in German:




Unfortunately I don't own the optional Floppy station - a Z80 CP/M box in its own right that used the MUPID only as a terminal and could double as a local BTX server - its good "graphics" capabilities meant that the MUPIDs were often used to develop BTX pages which could be stored and recalled on the floppy station.

BTX servers haven't been active for a long time, so the MUPID is only marginally useful today.

Unless ... someone wrote or developed one smile




Here are the CP/M and Mupid utilities as disk images for the floppy station and the MUDISK utility which you can use to connect a regular (DOS) PC to the MUPID and simulate the floppy station.


My Mupid C2A2 came with its keyboard disconnected which was easily remedied, but another error remains:

If you check this page


you can find a pic of the MUPID's start screen ... my MUPID starts drawing the logo of the Austrian telcom company, then my TV loses sync and I only get red and yellow dots zig-zagging across the screen.
Posted By: Bavarese

Re: MUPID C2A2 - 04/20/17 09:14 AM

See other discussion around Minitel / Prestel / BTX related hardware.

With all the effort necessary, do you think it will be a worthwile experience? BTX and its horrible DBT-03 modem were one of the reasons i refuse to buy Telekom shares to this day.
Posted By: rfka01

Re: MUPID C2A2 - 12/08/18 06:08 PM

More MUPID ... in fact another one that came with a different ROM revision (also with an odd ROM pair of 27256 and 27128) and the MUPID floppy disk station.

[Linked Image]

My first MUPID C2A2

[Linked Image]

This is a later ROM revision

[Linked Image]

[Linked Image]

This is the floppy station. The MUPID is only used as a dumb terminal at 4800 baud, the disk station is a fully self contained CP/M computer that can be connected (as many people did) to any serial terminal at the higher speed of 19200 baud. The disk format is a single density, FM, 10 sectors of 256 bytes on 80 tracks. It's essentially used single sided, in that the two physical drives are mapped to CP/M drives A: - D:

MUPID is an Austrian invention. German companies like Siemens or Grundig made sure the concept was sufficiently dead and their own flavour of BTX was chosen, before they offered their Mupid clones.

The archive on the FTP contains pictures, some documents, firmware for the two MUPIDs presented above, one for a German edition, the Grundig PTC-100 as well as firmware and disk images for the floppy station.
Posted By: Duke

Re: MUPID C2A2 - 12/13/18 06:31 PM

I'll add a partially working driver for the disk station soon. Here's a screenshot of it with no disk inserted:

[Linked Image]

Disks boot too, but the keyboard seems erratic:

[Linked Image]

[Linked Image]

It doesn't boot the disk you provided though, this is this one: ftp://ftp.informatik.uni-stuttgart.de/pub/cm/mupid/disks/mcpm.imd

There is also an alternate firmware for it at ftp://ftp.informatik.uni-stuttgart.de/pub/cm/mupid/roms/

This seems to be the Grundig FL100? Screenshot:

[Linked Image]

Maybe it expects some kind of special terminal?
Posted By: rfka01

Re: MUPID C2A2 - 12/13/18 07:42 PM

Hi Duke,
thanks for creating the driver ... the "CEPT" string seems to point to some sort of BTX screen codes, but I could be totally wrong.
Since the MUPID was a BTX machine that accepted "apps" sent over BTX, maybe these are the screen settings for the MUPID to act as a terminal.

The disk that's in the archive was in one of the drives but doesn't seem to belong to the system as it's MFM vs. the FM only MUPID disk station.

Since my floppy writing rig doesn't seem to be capable of handling FM, I'm awaiting delivery of boot disks to test my disk station.

Christian Corti put on additional firmware and disk images of his German version MUPID (which is Grundig branded), so I'm looking forward to testing more.

Posted By: rfka01

Re: MUPID C2A2 - 12/19/18 08:56 PM

Hi Duke, I'm going through a MUPID BASIC book to see if there is usable hardware information. MUPID apps ("telesoftware") could be transferred as BTX page payloads, and the book has this to say:

"BTX is a slow medium with its transmission speed of 1200 Baud. Even with "normal" pages which only contain text or graphic information, this can lead to nervous traits like drumming your fingers, chewing your fingernails or a change in smoking habits. This is also true for telesoftware. As tsw is loaded into RAM and there is no visible action on the screen, a phlegmatic character is needed to survive the loading time of a long program unscathedly."

Indeed. laugh
Posted By: rfka01

Re: MUPID C2A2 - 12/19/18 09:37 PM

0000h-7FFFh: bank free region

The system software of the CEPT MUPID (decoder software, BASIC interpreter, graphics) and user RAM areas are located in this region.

8000h-FFFFh:  banking region]
This region has four banks of 32K dynamic RAM each. Each bank occupies the same address area. A bank select determins which bank is actually accessed.
Bank 0: Screen area
Bank 1: Screen area and buffers
Bank 2 and 3: user area, e.g. Bank 2 - BASIC program code, Bank 3 BPES (Basic IDE)

Free memory areas:

The BASIC programmer can use the following memory areas for their own applications (assembler subroutines):
- 7600h-77FFh (511 Bytes): This (bank free) memory area is at the disposition of the user. Some utilities have been located in this area.
- TOPMEM is a user selectable part of Bank 2 or Bank 3. The standard topmem address is FD60h, this can be changed with the OPTION TOPMEM directive in the BASIC compiler
- The other RAM bank. At runtime, only one bank is used (usually Bank 2). For this reason bank read and write commands have been introduced (READ #0, WRITE #0, SETPOS #0, GETPOS #0, PEEK #0, POKE #0) which allow the use of the complete other bank (32K !!!)

Occupied memory areas:
- Bank 2
- Bank 3: If you work with the BPES environment, this bank is completely used by BASIC system routines (compiler, editor, clear text memory ...)
- 7D20h - 7FFFh: Used by the BASIC interpreter (program headers and stack)
Posted By: Duke

Re: MUPID C2A2 - 12/19/18 10:24 PM

Thanks, that is useful info.
Posted By: rfka01

Re: MUPID C2A2 - 12/21/18 06:22 PM

Here's a partial scan of the MUPID BASIC book ... I'll upload the PDF to the FTP once I've completely scanned it.

Posted By: rfka01

Re: MUPID C2A2 - 02/07/19 08:13 PM

I've uploaded scans of three MUPID books to the FTP, they can also be found here.
Posted By: Duke

Re: MUPID C2A2 - 02/08/19 09:52 AM

Thank you rfka. Unfortunately they are all a bit light on the technical details.
Posted By: rfka01

Re: MUPID C2A2 - 02/08/19 10:16 AM

Yeah, I know ... unfortunately I haven't discovered original hardware documentation. The three books were obtained through the Germany-wide network of university libraries.
Posted By: rfka01

Re: MUPID C2A2 - 02/12/19 09:09 AM

Team E suggested contacting the university professor who's credited with the invention of the MUPID, Prof. Dr. Hermann Maurer, and he's not only responded but contacted three guys of his team asking them to provide me with technical specs of the MUPID - there's a nice archive containing original schematics on the FTP now smile

They said that some emulation attempts over the years had failed - it would be nice to show them what MAME's capable of.
Posted By: Duke

Re: MUPID C2A2 - 02/13/19 04:18 PM

Wow, that's fantastic! Thanks rfka smile

And yeah, would be a great showcase for MAME.
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