Date: Tue, 28 Oct 2003 12:32:12 +0100 From: Marc Fonvieille <blackend@freebsd.org> To: Peter Pentchev <roam@ringlet.net> Cc: freebsd-doc@freebsd.org Subject: Re: Printer Setup (11.3.1.1.1) Message-ID: <20031028113212.GB583@nosferatu.blackend.org> In-Reply-To: <20031028103425.GV430@straylight.oblivion.bg> References: <3F9DF133.3000104@sitetronics.com> <20031028082305.GA583@nosferatu.blackend.org> <20031028103425.GV430@straylight.oblivion.bg>
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--tThc/1wpZn/ma/RB Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Oct 28, 2003 at 12:34:25PM +0200, Peter Pentchev wrote: >=20 > Errrr... I'm not sure it needed fixing :) Rather, IMHO rev. 1.79 might > need to be reverted. >=20 > Historically, parallel ports did indeed offer only one-way > communication: the computer sent data to the printer, and that was it. > Then things like EPP (the extended printer port) interface and friends > were developed, and the parallel port grew two-way communication, too - > this is exactly what the *last* sentence is talking about (EPP and ECP > were standardized in IEEE 1284, http://www.fapo.com/ieee1284.htm for > more info). >=20 > Serial port communications have always been two-way, AFAIK, albeit some > of them were just half-duplex, so only one side could talk at a time. > Oh you're right, I just had that half-duplex in mind. I always thought serial printers used half-duplex. > Thus, I think the text was correct as it was, before rev. 1.79 - > parallel ports were once only capable of one-way communication, but with > IEEE 1284 (EPP, ECP) they can do two-way now, while serial ports have > always been capable of two-way communication. >=20 I reverted the commit and added EPP, ECP in the last sentence, it will be less confusing. Marc --tThc/1wpZn/ma/RB Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.1 (FreeBSD) iD8DBQE/nlO781T1MWxkgcoRAltOAJ99MMxYRc16KVreoCM33Cceu/LbKQCgjBR/ FfaykXFA4xXM+hiCVq3ZniI= =pKrn -----END PGP SIGNATURE----- --tThc/1wpZn/ma/RB--
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