From mboxrd@z Thu Jan 1 00:00:00 1970 From: grant.b.edwards@gmail.com (Grant Edwards) Date: Tue, 19 Oct 2010 14:29:48 +0000 (UTC) Subject: [PATCH] Documentation about RS485 serial communications References: <20100408111310.524f7354@lxorguk.ukuu.org.uk> <4BBDD71D.1010700@evidence.eu.com> <4BFD1FB6.8050405@atmel.com> <4BFE2F38.8050200@evidence.eu.com> <4BFE41FD.2080804@atmel.com> <20100527102917.GB31253@pengutronix.de> <4C626CBF.9020609@evidence.eu.com> <20100811083214.21d2919e.randy.dunlap@oracle.com> <4C669120.8080707@evidence.eu.com> <4C686411.3060500@oracle.com> <20100815221906.GA24153@n2100.arm.linux.org.uk> <4CBD8EE4.5040808@evidence.eu.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 2010-10-19, Claudio Scordino wrote: > +2. HARDWARE-RELATED CONSIDERATIONS > + > + Some CPUs (e.g., Atmel AT91) contain a transceiver capable of working both > + as RS232 and RS485. Pardon my curiosity, but I've looked at a few AT91 parts, and I've never seen on with an internal transceiver -- nor does Google seem able to find any. Frankly, I'd be pretty surprised, since it would be very difficult (fab-wise), to build a mircoprocessor with I/O cells capable of withstanding the voltage levels specified in RS232. Can you specify to which parts you're referring? -- Grant Edwards grant.b.edwards Yow! I have the power to at HALT PRODUCTION on all gmail.com TEENAGE SEX COMEDIES!!