Re: Do UART require data structure/format for serial communication?

From	Dennis Lee Bieber <wlfraed@ix.netcom.com>
Subject	Re: Do UART require data structure/format for serial communication?
Date	2011-04-13 21:49 -0700
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On Wed, 13 Apr 2011 14:24:17 +0530, VGNU Linux <vgnulinux@gmail.com>
declaimed the following in gmane.comp.python.general:

> Actually I am trying to data communication between these 2 chips, but facing
> troubles in deciding a protocol to do the same.
> Do UART have any default protocols? For the moment I am trying to do it with
> Strings but not sure if that's the right solution.

	The only absolute protocol is that UARTs use a start bit, some
preconfigured number of data bits, with or without a parity bit, and
some defined stop bit (1, 1.5, 2 bit times) [the infamous 8N1 -- 8-bit
word size, No parity, 1 stop bit]. Even handling transmission start/stop
may be moved into software level (ie; a pair of control CHARACTERS is
used to permit/inhibit transmission <ctrl-q> and <ctrl-s> I believe).
Oh, and bit rate...

	All they do is take a parallel input and convert them to a serial
stream.

	It IS common for them to accept additional pins between them for
permit/inhibit -- RTS/CTS and/or DSR/DTR (or something like that).

	Anything else is purely by agreement in the software using the UART
for communication.

	For example -- does the receiving device want JUST a <cr> to
terminate a command (for example), or does it need BOTH <cr><lf> to be
sent. And if it needs both, will PySerial convert <cr> to <cr><lf> (I'd
hope not, as it would make sending binary data rather difficult)
-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
        wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/

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Re: Do UART require data structure/format for serial communication? Jean-Michel Pichavant <jeanmichel@sequans.com> - 2011-04-11 13:57 +0200
  Re: Do UART require data structure/format for serial communication? John Nagle <nagle@animats.com> - 2011-04-11 11:13 -0700
    Re: Do UART require data structure/format for serial communication? Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2011-04-13 21:49 -0700

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