Note that most (all ?) IR protocols are not
at all like the "normal" serial protocols used
over RS232 lines. IR comunications often uses
either Manchester coding (where a shift from
"0" to "1" = "0" and a shift from "1" to "0"
= "1") or PWM encoding (where a "short" puls
could be a "0" and a "long" pulse is a "1"). The
effect is that there is always a level shift (a
"level" is "1"/"0", "high"/"low", "carrier"/"no
carrier") in each bit. These codes are also known
as "self-clocking". Another effect is that the clocks
in the sender and recevier don't have to be
as accurate as when running standard UART comms, since
the receiver can adjust it's timing after each bit received.

So the UART can not (in most cases) be used for
IR comms.

Most (all?) IR protocols has a way to define a "start of
message", like a pulse larger then the "long"
pulse if using PWM. Most of the time, it's not 8 char
"bytes", the message is as long as is needed to
transfer the whole message.

With PWM the actual "buad rate" isn't' fixed, since the
"0" and "1" has different lenghts.

And as a sinde note, note that "buad rate" is not the
same thing as "bit per second"...
See :http://www.wikipedia.org/wiki/Baud_rate

Jan-Erik.

Andre Abelian wrote:

> On your [Olins...] project did you use hardware usart or software[?]
> Was it standard usart <start/8bit data/stop> and what
> Baud rate did you use?

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