Yay! I think that's cool. The TNCs were (are) intelligent modems.
They do have a terminal mode, in which you can interact in Eng […]
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Yay! I think that's cool. The TNCs were (are) intelligent modems.
They do have a terminal mode, in which you can interact in English with them.
Those with the original, American TAPR firmware, I mean.
It was used to operate the TNC from within a real glass terminal or home computer+terminal software.
Unfortunately, we Europeans dropped terminal mode in the 90s and began to use Hayes-like abbreviations in our TNC firmware ("The Firmware", TF). *sigh*
The idea was to use a computer optimized communication instead.
Hardware wise, these TNCs are Z80 single board computers. They technically could run CP/M, if enough RAM was installed.
Some even have an memory expansion, to allow for a mailbox (users can store messages in your TNC).
Here's a quick video of my PK-232, to give an idea.
It's a multi-mode model, with its own firmware. It can be replaced TF, though.
https://www.youtube.com/watch?v=f6_PNpWEhNc
Interesting is the auto-baud detection.
By typing a star (*), the TNC firmware would try to detect the terminal baudrate.
The same method was used in the days of our X.25 service (Datex-P, by our Federal Postal Agency/later operated by Telekom here).
The local PAD you'd called with your telephone modem or acoustic coupler had an automatic baud rate detection.
It was a dot ("."), followed by pressing the enter key.
Edit: Anyway, I didn't mean to spam this topic. I just meant to say that your chassis is a good choice.
SBCs were actually installed in such chassis in the 8-Bit era.
And in case you need further inspiration, you may want to have a look at some RTTY decoders of the 70s/80s.
They've used panels with switches and lights, too.