Shoehorning RS-232 Into A Minitel Terminal

In the early 80s, millions of terminals were handed out to French telephone subscribers. Nearly 9 million of these Minitel dumb terminals were in use at one time, and with that degree of ubiquity, we’re surprised we haven’t heard of them before. These boxes were usually connected to the outside world through their internal 1200bps modem, but [O. Blt] came up with this build (Google Translate link) so he could connect to a local machine with an RS-232 port.

After digging up the pinout for the Minitel’s DIN-8 port, [O. Blt] designed a little board around a MAX232 chip scavenged from an old motherboard. Of course there was a need to get the terminal to do something, so [O. Blt] used the Minitel as a display and remote control for Winamp. The project was successful, but not very useful – at 1200 bps, the refresh is very, very slow.

American readers may remember connecting to the Minitel network with their Apple ][s and C64s with CommunityLink, but this service was driven out of the market by the giants of pre-web dial-up, Prodigy and Compuserve. In any case, after seeing the AZERTY and alphabetic keyboard layouts of these old boxes gives us a feeling of nostalgia for a time before everything dealing with computers was standardized.

30 thoughts on “Shoehorning RS-232 Into A Minitel Terminal

    1. Yes infortunately true. I fully switch to qwerty at home (different ones us spanish portuguese and english, who was talking about stds?) but I still have one at work. Switching scks believe me!

  1. 1200 bauds is the modem speed, not the serial line speed. Speed is up to 9600 bauds.

    Refresh is still slow at 9600, but a minitel can be used as a linux console for a headless server.

  2. Wow. The ignorance is surprising. AZERTY is still the standard for France and Belgium. I’m also surprised that you haven’t heard of Minitel as hackers. In the late 80s it was the thing to hack even outside of france because of how cheap the terminals were.

  3. @Flo: Yeah, it’s standardized, but no one in their right mind would use it. The French are a bit weird when it comes to adapting to standards (->octet instead of bits, which makes their megabyte a megaoctet)

  4. @max: it seems that the French translated lots of words in IT. byte -> octet, computer -> ordinateur, and so on. French is a real language, you know :) On the keyboard layout side, there are lots of them in Europe :
    For example, I am working in Luxembourg, where you can find in every office Swiss French QWERTZ, Belgian AZERTY, German QWERTZ…

  5. @max:

    Yeah, the French are truly bizarre. Not only they use “octet” for byte, but also “ordinateur” for computer, “lune” for moon, “chaise” for chair, and so on.

    Actually, I have heard that they do not use English but a strange language called “French”.

    But, it get worse. It seems the Spanish speak Spanish and Russians speak Russian…

  6. There’s an emulator of a minitel server for the atari ST. Sources avaiable. I have a videotel (italian minitel) terminal myself, but I’m too lazy to convert the sources to something more usable or to set up an emulator and com redirection.

  7. @ Max: no one in their right mind would use qwerty post-typewriter, but somehow it is “standard” to do so.
    Btw, nothing wrong with octets imho.

    Pretty impressive that 1/6th of the country had these terminals at the time.

  8. it just so happens i stumbled onto that site a week ago, when i got my hands onto a minitel terminal as well.

    works exactly as described, like a charm. it is currently running as a linux terminal, showing some processor statistics with htop.

    it lacks a backspace key, though.

  9. There are a lot of keyboard standards besides QWERTY. French are not the only “weirdos” with locale specifics.

    I personally “owned” two versions of this terminal, the simple one and the one with a smart card slot. It was the standard way to access white page service. You could buy stuff from online vendors of the time like La Redoute, browse weather forecast, get your national exams results, browse business registry info, get train tickets …
    The most financially profitable services were adult chat rooms.

    Nowadays a few professional services are still available that way but Internet mostly killed any interest in this network. The number one reason for its success was that it was provided for free when you opened a phone line. The cost per minute was very high though.

  10. @Max
    No one is using US keyboard, neither in France, nor in Germany or anywere else in continental europe, except sometimes in american companies. That makes a lot of people who do not have the right mindset.

    And by the way, octet is not a standard, it is a translation.

  11. Something is wrong in this article. Minitel were not in use, it is in use. Its end is planned in september 2011, even though most french believe it died long time ago.

  12. An interesting project, but I’m a t loss to what “I” would use a dumb terminal for these days. I ques I could connect it to one of my old packet modems, and a scanner to monitor the local amateur radio APRS traffic.

  13. @haltux
    “No one is using US keyboard, neither in France, nor in Germany or anywere else in continental europe”

    Wait, what? Then what am I typing on? As a Dutchman, I haven’t seen any other type of keyboard around here. I know Belgium and France have their AZERTY, and Germany its QWERTZ, but around here everyone is quite happy with their QWERTY. That’s US-International, mind you, with an @ above the 2, instead of an “.

    Anyway, back to the actual hack. It is a lovely little thing. I love it when people find new ways to use old technology, especially in such an elegant non-invasive way.

  14. I’m french living in Spain, and qwerty keyboard has its own variant here. Azerty is just another mapping, macs are also using their own variants. US mapping is just more frequent, but not a standard, especially for accents. Anyway minitel are not so common because they were rented by France telecom for users. Most of the people handed back to France Telecom (orange now) who has probably destroyed them. I have still Mine and it is still perfectly working.

  15. well AZERTY or QWERTY keyboards are quite a small problem compared to that prehistoric imperial units…Now we are rich enough to buy a ruler and don’t try to measure with our toes and fingers ^^

    Regarding Minitel, it’s said to be the main reason why Internet took so much time to settle in France. You were able to do quite anything online with that little terminal, but don’t tell me to use one again lol

  16. I like the Alcatel terminal with the alphabetic keyboard. Nice piece of industrial design.

    We had several similar PSTN connected terminal networks in the UK at the time. Prestel was used for government stuff, worked at 1200/75 baud and had blocky colour graphics. The OU ran some of its distance learning courses over headless 300 baud terminals where the output was a line printer. Anachronistic garbage compared to Minitel sadly.

  17. They say “octet” to make it very explicit that they’re talking about an 8-bit data object. Not all hardware always used 8-bit bytes, or single-byte characters, or word sizes of 8, 16, or 32 bits, or unsigned bytes, or five seven-bit-ASCII characters packed into a 36-bit word, or five-bit Baudot code characters.

    During the 1980s, it was becoming very common to use 8-bit bytes to represent a character (though ASCII was only seven bits and there were multiple standards about how to handle the 8th bit, whether to use it as parity or one of many extended character sets, and whether codes 0-31 were control codes or other things like line drawing or hearts and spades and smileys), and word sizes were mostly standardized on 8, 16, and 32, but it was hardly universal, and you’d have chips like the 68000 where the I/O bus size was 16 bits (so ints were usually 16 bits) but the address space and registers were 32 bits.

    And 1200 baud slow? That’s roughly 1200 words per minute, so it’s as fast as you read, and a lot faster than you can type.

  18. There had Querty Minitels too, prototypes based on the Alcatel M1B, but in black or beige, no brown, as far as I know. Those were designed to conquer Us marquet, which kinda failed.
    Only Minitel 2 and later were able to send 9600bps, early models were able to 4800bps max.
    The keyboard on the pic shows a very late one, probably with smart card reader, and graphics ability.
    Some have slide-inside keyboards (Philips/RTIC), some have slap and close ones (Alcatel/Telic), others have fixed one (Matra), I assume with variants and colors, a collector can get between 30 and 50 units without any double.

    For the refreshing rate of the screen, just get the serial rate divided by 10 (1 start bit, seven data, one parity, one stop) provided you have no special attribute (color, size, underscore, anything…) then, you have to make the result divide the number of characters in the screen, which can be 40×24 or 80×24 (ignoring the state line in the upper).
    Not to be annoyed by the upload slow rate of 75bauds (same as 75bps because of the internal modem’s ability/limits), there had a send buffer of 200 keys, if my memory doesn’t fail, so it is enough not to lose strokes along (especially if you consider the keyboard’s touch and feel). Anyway, there didn’t have word processors service, so it was rare to have more than 20 characters to send at once.
    Soon (maybe since the serial connection was available), the modems had the ability to be reversed during session, so the 1200baud speed was practically usable both ways.

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.