🧵 cont'd
7. yay, dumped in 3 seconds with zero issues. we now have the world's first ROM dump of an AlexTel terminal! 🎆
why did i go through all this effort to dump the rom? because i want the juicy alextel font glyphs hidden somewhere inside!
thanks to @Screwtapello whose recent work on extracting the DEC VT-320 font from the DEC terminal, i *should* be able to figure it out
https://teh.entar.net/@Screwtapello/113848235903486857
🧵cont'd
6. now time to dump that norpak ROM. the underside read "jl27c512d/n331018". i am no @foone so it took me a few tries to figure out what it was. a quick web search showed that it was some variant of the 27C512 - a 512 kbit EPROM (that's 64 kbytes).
the software i use for reading/writing roms on my TL-866/II programmer is called XGpro. when you type in 27C512, you get about 30 different options for that rom.
i knew a few things about it: it's a 28-pin package, and a DIP socket. so that narrowed it down to 20 choices.
i had to go through every single manufacturer option, read the chip, and watch it fail about 10 times. i finally stumbled on the right manufacturer (since "JL" wasn't an option) ... it read properly using Texas Instruments as the manufacturer: SMJ27C512
🧵 this is really fun. today i decided to start documenting and preserving the Bell Canada AlexTel terminal - the canadian equivalent of the beloved Minitel videotex service.
this little wonderful CRT terminal machine (with 9600 baud modem!) has very little historical or technical information out there, and it's time to fix that.
@vga256 So the guy had two:
a) Turned on to the calling screen, but the top of the CRT was a bit screwed up.
B) Screen powers up, but is blank. But had some extra ports (serial, parallel)! Red LED also not on.
I found the ports very interesting so I went with that. Since it wasn’t technically ‘working’ he only asked $60.
So now I got it.. Right choice? Hmm, 🤔
I’m sure it’s fixable but so little is known. I’ll try opening it. Maybe some recapping? (Which I’m not an expert at).
i had a lot of fun with this tonight.
back in the 80s and early 90s, Bell telephones in canada experimented with an on-line videotex service called ALEX/AlexTel. it was very much like France's Minitel system, except that it supported several protocols - videotex/minitel, NAPLPS and Telidon.
ALEX hasn't been very well preserved or documented, and after buying a little AlexTel terminal a couple of years ago, i've slowly started preserving and documenting as much of its history as possible.
tonight i reconstructed the Alex logo - beautifully stark yet futuristic - in a vectorized format. i've exported them to EPS and SVG here:
http://www.dialup.cafe/~vga256/art/alex_logo.eps
http://www.dialup.cafe/~vga256/art/alex_logo.svg
There's someone selling an Alex terminal in Montréal for 200$. Kinda want.
Alex was Bell Canada's Minitel, in limited markets from 1988 to 1990, and killed in 1994 (reason: pricy to use and the advent of the internet/Web).
I remember only using one once in a museum expo about "the future" in 1989.
It can be used as a VT100 terminal (and all the modern fun stuff you can do with Minitel-like machines?) so there's that.
[1/3] in the late #80s Bell canada created an interactive videotex service few have ever heard of called #AlexTel
like france's #minitel terminals, the alextel is similar in design and layout. it houses a small mono CRT inside the plastic shell, and a fold-out keyboard that neatly folds up to hide the screen.
inside is a 1200 baud modem that you'd use to connect to bell's alextel dial-in service
can't wait to try this out on a dial-in #bbs
