• Please review our updated Terms and Rules here

Olivetti ETV 300 : Can I use the typewriter part as a serial terminal to mimic a teletype?


Experienced Member
Mar 11, 2014
Hi! Cannot find a manual, looking for people with experience with this unit.

Title says it all !

Thank you!
A little Google-ing and translating from this website:

The system also included a typewriter (it appears to be from the ET series) equipped with a serial interface LCU ( Line Control Unit ) so as to use the keyboard section as input and the printer section as output. The connection between the typewriter and the ETV300 was serial RS232.

So it looks like you can use it as a terminal.
Besides others I have fully working ETV 300. The system requires an Olivetti ET series (not any) to operate as it uses the typewriter as keyboard and printer. You can not just use any ET series typewriters, there are some conditions:
- The typewriter needs to have the optional ETV kit. That is a serial interface with special firmware (LCU, line communication unit), hard to find. The ETV kit also includes stickers or additional keys to stick on the keyboard, that depends on the ET series typewriter.
- Boot disk for ETV 300 to support the typewriter model, additionally the boot disk must match the national keyboard layout and daisywheel, otherwise the system will print nonsense and you'll write nonesense. So german boot disk with english typewriter will not match. Boot disk with ET 121 support will not fully support ET 225 functionality, etc.

Typewriters known to work with the ETV 300 / ETV 350 if they have the matching ETV kit:
- ET 121
- ET 225
- ET 111
- ET 112
- ET 115
- ET 116

ETV 350 is mostly the same as ETV 300, but it is based on 3.5 inch disk drives, format compatible with standalone ETV 240 and ETV 250. Most popular typewriter for ETV 300 was the first two in the list, ET 121 and ET 225, I have both of them with ETV kit, but I only have german boot disk to support german ET 121. My german ET 225 basically works but prints some wrong caracters and does not support the enhanced text attributes of the ET 225. I have italian boot disk to support ET 225 but my ET 225 is german model.

Note, that you need the matching ETV kit for these typewriters, so for example a ETV kit for ET 121 does not work on ET 116 and vice versa. (ET 111 + ET 115 uses the same ETV kit, ET 112 + ET 116 uses the same ETV kit). I remember also a note that there was also an ETV kit for the little Praxis 45D portable typewriter, but never seen this. It will also not help you if you find an ET with the generic LCU, it needs to be the LCU with ETV firmware, these LCU interfaces is not just an interface, they have their own CPU to translate between the typewriter and the ETV. Note, that there also ET series typewiters with ETS kit, the ETS 1010 and 2010 are different (CP/M 86 based) wordprocessors incompatible to the ETV series. For ET 112/116 there is also ETV kit for MS-DOS based ETV 500, this is again a different thing, and there is ETV Kit vor ET 2000 series to connect MS-DOS based ETV 2900 / VM 2000 to these, again a very different story.

Like all LCUs for the Olivetti typewriters the ETV kits are really hard to find by today separately and those for ET 121, 225, 111 and 115 are not that easy to install, it's not plug&play, you need to open the machines, add option board, probabbly add EPROM to empty socket, install cables and connector at the housing, add/replace keycaps, and so on. Without the technical manual of the typewriter a really hard job. Only at ET 112 and ET 116 it is quite easy, just plug the ETV kit LCU at the rear connector.

More easy is to watch ebay and other platforms for the matching ET series typewriter and hope that there is one with a silver sticker on the top which is having the magic letters "ETV 300". But also for that you need a lot of luck. In the last 10 years I found only one separate one.

That is my ETV 300 with ET 121. I am able to convert files from modern PC down to there, so I can do ASCII art based on JPEG photos.

My ET 225 with the magic silver sticker...

Watch out for this!

My ETV 250, this one is fully integrated, word processor computer and typewriter all in one. I also have ETV 240 which looks the same, but it has completely ROM based software, so no boot from (3.5 inch) floppy like this one.

My ETV 210s, uses a thermo transfer print head similar to IBM Quietwriter. There is a very similar Quietwriter typewriter from IBM. It has ROM based CP/M and wordprocessor which is compatible to ETV 240/250/300/350.

My ETV 260 with 20 MB SCSI harddisk. There is also a 2x 720 kB floppy disk version without harddisk. This is the MS-DOS based successor of the ETV 250.

My ETV 2700, successor of ETV 260, with 20 MB IDE harddisk. There is also single floppy version and double floppy version, both without harddisk.

My VM 2000 with ET 2450MD. The monitor is the MS-DOS computer with 1x or 2x 720 kB floppies, no harddisk.

My ETV 2900 with ET 2200 typewriter. VM 2000 is the same as ETV 2900, only different BIOS.

My ETV 4000s, MS-DOS and Windows 2.0 based, uses a thermo transfer print head, can print graphics and even includes a hand scanner. I also have the Triumph Adler OPS 400 version of it.

I also have home video typewriter CWP-1 and Editor 100.
Last edited:
I got this kit. All matching. ETV 300 with ET 111. Currently cleaning it. Lots of corrosion.

Can I test the typewriter serial interface by connecting it to a serial port on my computer and watch with a terminal program?


  • 5ACF869B-6ECB-4FD3-B2E1-FFF9A83660B7.jpeg
    1.7 MB · Views: 4
Nice find!

The communication parameters between the typewriter and the ETV system are not documented, they are hard coded in the boot disk and the LCU firmware, and it might use special (software) protocol as an ET series typewriter with standard LCU (serial interface, I have a LCU 116s for the ET 116 with two serial ports, it runs nice as a Diablolo 630 compatible printer) can not communicate with the ETV. The cable looks like full featured with hardware handshake. You will see that the ETV stops while booting and it waits for the typeweiter to get online. So typewriter must be connected, switched on and you have to press some key to get it online to send that message to the ETV. I don't know the key kombination you have to press on ET 111, I only know for ET 121 and 225 - So I hope that you have user manual or the stickers have been put on the keyboard of the ET so you can see. So it may not make sense to use the system separately, they are a team.

I was in touch with someone somewhere in Italy, he was here in the forum, and he had the ETV 300 without typewriter, and he was not able to find out the parameters because the ETV waits until the ET sends the correct message. I got italian diskimages from him, containing some special software for the ETV but then unfortunatelly the contact lost. His plan was to control the ETV froma PC, so I don't know if he managed to do. The diskettes do not contain a lot of CP/M commands, just what is necessary to operate the system, PIP.COM and STAT.COM, that's it - there is even no FORMAT.COM to prepare diskettes for the system, in old time you had to buy preformatted disks from Olivetti. But you can use some software for MS-DOS (PC-Alien, 22disk, Omidisk, etc.) to format/copy (empty) disks and filetransfer.

You can run a lot of CP/M software on it as long as you have set up the terminal emulation in the program correctly. Easy to run ZORK 1, 2 and 3 on it as it only uses CR+LF, I can provide disk image to you (but with german keyboard layout, or italian). Can you please image the system disk(s) which you have and share with me? I have also a disk image with WORDSTAR, but on my ETV 300 it does not display correctly, the terminal emulation may not set up correctly or my boot diskettes are too old. Is your ET 111 having french or english keyboard layout, or is Canada special?

If you have any questions regarding the system and the typewriter, just ask. I have the service manual for the ET 111 in german. The most important thing to do is a cleanup of the mechanics of the typewriter, specially the transport mechanism for the ribbon usually is dirty and blocks. The ET 111 has a LED line over the keyboard for the status. When the autodiagnostics after power on detects a problem it stops and displays an error code on the LED line. With the service manual I can decode it to tell you what is the problem.

I also have service manual for the ALPS floppy drives used in ETV 300, but usually they are still Ok. If you know some guys which are familar to adjust early Commodore VC 1540 / 1541 floppy drive or Apple II dual disk or Apple 2C floppy, they use the same ALPS floppy mechanics, the Commodore is without the shugart interface - but the drive mechanics and it's connectors for head, step motor, sensors, etc. are the same pinout.
Something about your entry question...

Maybe you can use the whole thing like a terminal. Some of the ETV 300 have a 2nd serial port and the MWP (monitor word processor) application has a TTY menu.

So if that, then you start the ETV and the ET, let it boot, and navigate to the TTY menu, and then you can connect to somewhere.
Wow, thank you for your help!
Here's the keyboard layout attached to answer your question. It's basically a US keyboard with different special characters keys.

The ETV 300 part of it doesn't work yet. I suspect corrupted memory chips. I don't have the cable between the ET 111 and the ETV.

I do not have the operating system either.

Maybe someone with good Z80 asm skill could patch the ROMS to turn the ET 111 into a TTY terminal to be able to use it as a teletype. I would like to see that.


  • IMG_1193.jpeg
    1.6 MB · Views: 10
Some error codes


  • IMG_1206.jpeg
    3.4 MB · Views: 12
  • IMG_1207.jpeg
    2.3 MB · Views: 12
Here's the situation when powered on.
If anyone can give me some guidance. This looks like a RAM issue to me.


  • IMG_1219.jpeg
    2.1 MB · Views: 11
  • IMG_1218.jpeg
    2.9 MB · Views: 11
  • IMG_1217.jpeg
    4.2 MB · Views: 13
  • IMG_1216.jpeg
    3.2 MB · Views: 13
  • IMG_1220.jpeg
    2.2 MB · Views: 13
Yes, that is video memory related. The graphics is on the add on card, so memory is easy to find.

The system disk is on the picture the upper right one. For the error code I'll have a look later.
Wow, so it's changing. That means the problem is not so strong, but I pulled out the service manual now and it is problem in the baseboard. As it's changing it is maybe only (hopely) dirty sockets.

The service manual of ET 111 shows only the codes for electronic problems. LED 11 to 23 is mechanical part, but that's not in the manual. If you are able to fix the electronic problem, and if it stops at the LED 11-23, we'll check further, maybe then the the technical manual for ET 112 helps, even if it's printer is slightly different (DC motors with encoders instead of step motors). From the manual of the ET 109 I see the mechanics is tested in this order, should start at LED 11 on ET 111:
- tab motor (moves print head left/right) (DIPON)
- selection motor (turns daisywheel) (DIPON)
- ribbon service motor (CHONI)
- linefeed motor (CHONI)
These motors have some sensors like finding left border, find the underline character ("_") for start position, end of ribbon sensor and linefeed sensors, and these are also used for diagnostics.

The base board so you can identify the chips from auto diagnostic LED error message.

So in the upper part of the board drawing you have the CPU, ROM, RAM, IO, etc., in the middle you have the amplifier logics for controlling the mechanics and getting the sensor status and below of the dotted line you have the power supply.

Maybe it is already a good start to try to charge the battery or replace it by a new charged one. That could fix the issue already.