On 2013-01-30, Jean-Pierre Tosoni <jp.tosoni@xxxxxxxxx> wrote:
>
> Well, you need to ascertain that the previous frame is all out AND
> the RTS has dropped before sending a new frame. Else the receiver
> might think it is the same long frame. Using TXEMPTY interrupt avoids
> setting an extra timer. However in the real life you are half-duplex
> and never send two frames in a row without waiting for an answer.
> Other than that I agree with your remark.
>
>> rare. But this function is not especially related to RS485. It is
>> also applicable in RS232 mode. So in my view it is not the
>
> True, it applies to some half-duplex RS232 radio modems too AFAIK.
It applies to half duplex modems and line-drivers whether they're
radio or not. Believe it or not, Bell-202 half-duplex over plain old
copper wire is still used a lot in the process control industry.
But, because of the general brokeness of both Windows and Linux serial
drivers when it comes to half-duplex communications, many of the
Bell-202 modems sold these days have automatic tx data detection and
handle the "RTS toggle" function themselves.
--
Grant Edwards grant.b.edwards Yow! Psychoanalysis??
at I thought this was a nude
gmail.com rap session!!!
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