Re: History of Hayes Modem

Paper-tape reader and punch control was an option of the Teletype, not

> the modem. It could be used even on direct connections.

That's true. I felt the original posting implied that Hayes invented something entirely new; which wasn't quite true. The point I wanted to make was that prior to the Hayes instruction set developed with their modem, there already existed remote control options to control terminal equipment. Yes, Hayes further automated and streamlined the functionality, and moved some of it from the terminal equipment to the modem.

One Hayes command -- automatically turning off the modem sound of dialing and connection handshake -- resulted in fraud. PC terminals would be sent a program that would do that and thus secretly be able to dial anywhere, such as an extremely expensive overseas call to a weird corrupt location.

In computer time sharing usage, most Teletypes used plain friction feed platens. But they always offered a sprocket feed for pre-printed business forms. You had to be more careful with those because a control-VT (vertical tab) -- ignored on friction feed units -- would cause a page eject on form feed units and you could inadvertently dump a lot of paper on the floor.

When I transitioned from Teletype to computerized PC terminals, I was disappointed that I lost the control tape-reader on/off functionality. I had programs that would call for off-line prepared tapes, this didn't transition over to computers without rewriting program. I don't believe the telecom programs (Telix, Procomm) could do anything with those control commands.

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hancock4
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