Here we go. Another case of Mysterious Hardware from the 80's.
So in the early 80's while AT&T was cranking out Unix PC's and PC6300 clones one of the neglected corners of their R&D lab decided to build a terminal for the home or the office desk. Obviously they ended up never being a commercially viable product and after a few years of poor sales they were withdrawn and have pretty much vanished from existance. It seems all that remains now are a few scant magazine articles that google
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Finally after almost two and a half years of work, 32 lines of code and 12 pages of diagrams it was finished. The first CCU for a model 33 designed exclusively to control a Hayes Smartmodem hidden away inside the stand while looking completely original, being completely modular AND bridging the gap from the early telecommunicating days to the modern era was completed.
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In the meantime a fellow from out east gave me a shout. He knew that my teletype was using a wooden stand I built myself. By chance he had just bought a basketcase model 33 that he was about to trade away for a better one but the new owner didnít want the stand. A small fee was agreed on and a week later I finally had a proper stand for my teletype. It was grubby and rusty but Iím not complaining and it looked a lot better after it was given a cleaning.
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Now is the point where bugs began to come out of the woodwork.
Once the Pro Mini was programmed I began playing with sending commands to the modem using the buttons exclusively. The first issue was that single presses would repeatedly fire off commands, resulting in erratic behaviour and unreliable operation. The assumption was that the switches were inducing a level of keybounce and the micro read each instance as me pressing the button. Initially
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I decided at this point to make a small modification. Initially when the phone was off hook the DIAL lamp would remain illuminated alongside the OH lamp on the modem but I wanted to make it a little more dynamic. Again using the CD signal I was assisted in designing a small circuit that when only OH was active the lamp would blink and when CD came up the lamp would go solid indicating a connection had been established.