• Please review our updated Terms and Rules here

Mysterious 80s computer

P

P101

Member
Joined
May 4, 2026
Messages
30
Hello everyone,
I'm new to this group and I'm asking for help: is anyone familiar with this computer marked SANWA 131A, made in Japan?
I'm very curious because it only has an CANON FDD, a LCD display, and a 40-character dot matrix printer with no I/O ports other than a Centronics port.
The keyboard appears to have a German layout.
The processor is a SHARP Z80A-CPU-0 with 64KB RAM and two 2732 EPROMs.
I don't have a floppy disk and I don't even know the operating system (CP/M or MSX-DOS?)
I couldn't find anything online.
Thanks to anyone who can help me.
Best Regards from Verona, ItalyFront.jpgLabel.jpg
 
Pretty sure that is just an electronic typewriter. You can type one line of text, review it on the LCD and press print to send it to a centronics printer.

Save and Search keys are most likely for saving texts to floppy disk for later print-outs.
 
Timo W. said:
Pretty sure that is just an electronic typewriter. You can type one line of text, review it on the LCD and press print to send it to a centronics printer.

Save and Search keys are most likely for saving texts to floppy disk for later print-outs.
Click to expand...
That could be a valid hypothesis.
I'm attaching the only port present, "PRINTER IN-OUT."
Perhaps it also captured text sent to a Centronics printer.
I can't explain the display's size, only 40 characters and not 80.
The most recent chips date back to 1985.
 

Attachments

  • Printer IN-OUT.jpg
    Printer IN-OUT.jpg
    98.8 KB · Views: 24
What is the dark grey part top-left of the first picture? It looks like an output for a paper roll. Maybe it is a label printer. That could explain the small screen.

Regarding the printer connector at the back: it seems to be a male so I assume it is a serial port, not Centronics.
 
Ruud said:
What is the dark grey part top-left of the first picture? It looks like an output for a paper roll. Maybe it is a label printer. That could explain the small screen.

Regarding the printer connector at the back: it seems to be a male so I assume it is a serial port, not Centronics.
Click to expand...

Yes, it's a nice unbranded 7-pin printer with the "R-7HB" marking on its PCB.
I'm a novice, but I think there are too many wire-connections to the printer for it to be serial.PRINTER.jpgPrinter MB Connection.jpg
 
Yes, that type of connector is more than likely an RS232 (or 20 mA current loop) interface.

Just because the LCD display is 40 columns, that doesn't mean that is all it can do. In theory (if it is some form of word processor) it may be a one line 40 column 'window' into the text buffer. Notice the cursor keys. They could be used to scroll the window around the document for editing purposes.

Yes, it probably has an integrated 40 column thermal printer.

The photograph did (initially) remind me of an AIM-65 - but it clearly is not one of these...

Dave
 
daver2 said:
Yes, that type of connector is more than likely an RS232 (or 20 mA current loop) interface.

Just because the LCD display is 40 columns, that doesn't mean that is all it can do. In theory (if it is some form of word processor) it may be a one line 40 column 'window' into the text buffer. Notice the cursor keys. They could be used to scroll the window around the document for editing purposes.

Yes, it probably has an integrated 40 column thermal printer.

The photograph did (initially) remind me of an AIM-65 - but it clearly is not one of these...

Dave
Click to expand...
Hi Dave,

hahahahaha :)

I bought this computer because I thought it would be an upgrade from my first computer, an AIM65: keyboard, display, 20-character thermal printer, and nothing more :)
There was also a 40-character AIM65.
The printer on this SANWA isn't thermal.
This weekend I want to dump the two 2532 EPROMs to find some more information.
 
But 64K RAM for a electronic typewriter? And not even "good paper" for the task?
 
64K seems reasonable for a mid-80s model since that would be a single RAM bank. Electronic typewriters often had good amounts of memory; even the IBM Selectric Composer from 1975 had 8K.

Narrower printouts on terrible paper were common for the glue phototypesetting industry. No idea what the intended workflow was with this typewriter but I wouldn't be too surprised if immediate editing was done using the narrow paper before a proper printout went to the full size printer. Rather a more industrial design since the printers that could fit inside a luggable typewriter were not up to the task of generating hundreds of pages a day.
 
If it was a word processor, it would at least have a backspace key, and probably dedicated function keys for common commands/formatting... not to mention a full-width printer.

And the fact that it has a 7-pin printer means it would produce ugly-looking text, without proper descenders. The "small" key suggests to me that it defaults to all-uppercase, and instead of true lowercase, it has ꜱᴍᴀʟʟ ᴄᴀᴘꜱ, like the TI-99/4A.
 
That printer looks very like the one I used, and still have packed away somewhere, on my SIM1.
It was avaliable as a kitset, so bare mechanism with minimal electronics.
 
Ruud said:
What is the dark grey part top-left of the first picture? It looks like an output for a paper roll. Maybe it is a label printer. That could explain the small screen.

Regarding the printer connector at the back: it seems to be a male so I assume it is a serial port, not Centronics.
Click to expand...

I removed the printer connector board.
From the PCB, I don't think it's an RS232 or 20 mA current loop interface.
I see an 8-bit bus and think it might be a Centronics parallel interface.
Correct me if I'm talking nonsense: I'm here to learn from the experts. :)

PRINTER CONNECTOR - FRONT-REAR.jpg
 
Update:
I dumped the two internal 2764 EPROMs (they weren't 2732...)
I find the ASCII content interesting; I have the impression that the computer was dedicated to label printing (ZIP CODE, CODE SORT).
Could it be that there was no operating system and that the EPROMs were only managed via function keys?

I find this interesting:
DISK CLEAR YES? YES: Y NO
DISK FORMATTING
INSERT MASTER DISK
INSERT NEW DISK
DISK NON FORMAT

I'm not familiar with this forum; is there a Files area for computers where I can save the HEX files downloaded from the EPROMs?
EPROM.jpg
This is part of the DUMP (.BIN):


H.SANWA SPEEDER MODEL-131AþINSERT DISKþKEY FUNCTION READYþ PRINT > # :þREGISTRATIONþDISK FULL TYPE ANY KEYþ NO.>þSEARCH > 1: DATA 2: NO.þZIP CODE SORTþALPHABET SORTþ þ>>> SEARCHING <<<þSEARCH ENDþ DATA >þPRINT > 1: DATA 2: NO.þPRINT ENDþDATA SAVINGþZIP CODE: : ALPHA: :þDATA LOADINGþWRITE PROTECT ERROR TYPE ANY KEYþDISK CLEAR YES ? YES: Y NO: NþDISK FORMATTINGþDATA-IN READYþPRINT ERROR TYPE ANY KEYþDISK ERROR TYPE ANY KEYþDISK NON FORMAT TYPE ANY KEYþNEW LABEL REQUIRED TYPE ANY KEYþLIST CHECKþINSERT MASTER DISKþINSERT NEW DISKþCOPY ENDþPRINT MOMENTARY STOPþ LIST NO.> :þ LABEL > :þALL PRINTþFLOPPY DRIVER CHECKþINPUT ERROR !! TYPE ANY KEYþ LABEL SIZE > :þNOISE ERROR TYPE ANY KEYþFLOPPY DRIVER ERROR TYPE ANY KEYþDISK ERROR NO. TYPE ANY KEYþSYSTEM CHECK : R F P K D (E-10)þRAM CHECKþRAM NO FAILURE !!þCOMPLETE SYSTEM CHECKED NO FAILURE !!þRAM FAILURE : BIT- ADDRESS-þDISPLAY CHECK : OK - Y NO - NþDISPLAY NO FAILURE !!þTEST PRINT : OK - Y NO - NþPRINTER NO FAILUREþFLOPPY DRIVER NO FAILUREþINPUT KEY :þKEYBOARD NO FAILURE !!þDRIVER FAILURE (TK- ST- )þDISK FAILURE (TK- ST- )þKEY FAILUREþPRINTER FAILUREþSORT> 1:ZIP CODE 2:ALPHABET 3:NO.þ ZIP CODE > :þ ALPHABET > :þ NO.> :þNUMBER OF DESIGNATED CODE -þ PAPER > : " " (1:LABEL 2:NON LABEL)þPRINT POSITION> :þ@ABCDEFGHIJKLMNOPQRSTUVWXYZ[¤]^_0123456789:;,-./ ÿÿ‚ƒŽÿÿÿÿ` ÿÿÿÿÿÿÿÿÿÿÿÿïÿÿÿÿÿÿÿÿ{ÿ}ÿ-í!"#$%&'()*+<=>?ÿÿÿÿ ÿÿÿÿÿÿÿÿÿÿÿÿ„ÿÿ‡ÿÿÿÿ…ÿ‰ÿ†€ˆŠÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿabcdefghijklmnopqrstuvwxyzÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ ÿÿ‚ƒŽÿÿÿÿÿáÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿõÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ ÿÿ‚ƒŽÿÿÿÿ1234567890-^¤QWERTYUIOP@[ASDFGHJKL;:]ZXCVBNM,./_þSAVE ŽSRCH ‚RETURN DOWN UP PRINT ƒSPACE REG LEFT RIGHT CTRL-A „þÿ1 * * * * * * PRINTER CHECK * * * * *^*ÿ2 SANWA SPEEDER ÿ3 MAGNIFICATION <SPEEDER> ÿ;4 EMPHASIZING SPEEDER ÿ;5 3 AND 4 <SPEEDER> ÿ6 PRINTER CHECK COMPLETE
 
I don't know if you have enough posts yet but there should be a button just below the entry box labeled Attach Files. The files should be small enough to fit, especially if placed within a ZIP file. Then, anyone interested in them could take a look and suggest a longer term repository.
 
krebizfan said:
I don't know if you have enough posts yet but there should be a button just below the entry box labeled Attach Files. The files should be small enough to fit, especially if placed within a ZIP file. Then, anyone interested in them could take a look and suggest a longer term repository.
Click to expand...
I attach the HEX files of the 2 EPROMs HN482764G (E-10-2 and E-10-3) for the SANWA 131A computer
 

Attachments

Solved!
I've finally managedData Entry.jpg to understand and get this mysterious computer working.
Thanks to everyone who responded: every reply helped me better focus on the problem.
If it can be of help to others, the solution came to me via GeminI after I handled the questions to analyze the Z80 firmware (unusually large) and the events via keyboard input.
I thus discovered that the SANWA 131A computer is a label manager and printer (for shipping) with the archive stored on floppy disk and that it doesn't use an operating system.
By analyzing the floppy disk drive settings, I also discovered that the floppy disk (DS-DD) must be preformatted in CP/M.
I still haven't been able to print, but it's not a big problem now.
I'm glad I found this forum: I'll be needing your expertise again.
 
Many hands make light work - or, in this case, a computer!

Well done.

There are various formats for CP/M (unfortunately)...

Dave
 
You must log in or register to reply here.
Back
Top