From mboxrd@z Thu Jan 1 00:00:00 1970 From: clemc at ccc.com (Clem Cole) Date: Fri, 28 Feb 2020 17:28:14 -0500 Subject: [COFF] 52-pin D-Sub? In-Reply-To: <20200228220532.17F741ADFAF@yagi.h-net.msu.edu> References: <905CE999-5601-4521-847B-B2146C60B564@serissa.com> <6a44c9e7-1e7b-bd0e-df1c-6e2208e8b780@kilonet.net> <20200228220532.17F741ADFAF@yagi.h-net.msu.edu> Message-ID: On Fri, Feb 28, 2020 at 5:12 PM Dennis Boone wrote: > > using the secondary pins as well. > > Best I could tell, the major intended purpose of the secondary circuits > was to implement autodialer, especially when those handshaking signals > on the primary were down because there was no connection, so you > couldn't do anything through them yet. > The autodialer is a separate spec. It's ECMA RS-4xx something IIRC, I forget the number and I'm not near my books. That was the DN-11 from DEC which talked to an AT&T 801 dialer. It used RS-232C electrical signals, but it's actually different than RS-232C (IIRC, Able called them a 'QuadraCall'). The way auto-dialing is spec'ed, is that a single dialer supports N modems. The Out-Band dialing stuff was an invention of Hayes who clearly had not read the AT&T (later ECMA) spec. > > Was there anything else in mind during the spec process? > RJE stations. -------------- next part -------------- An HTML attachment was scrubbed... URL: