I’m implementing an UART for a 21161n DSP as it’s shown on the EE-191 Analog Device’s
document.

http://www.analog.com/UploadedFiles/Application_Notes/399447663EE191.pdf

According to the schematic two flag pins can be optionally connected to manage the CTS and RTS
control signals.

Could anybody explain me where may I connect them (what FLAGx and FLAGy are?) and what’s their
utility?

Thanks,
Hori

On Fri, 14 Jul 2006 h...@yahoo.fr wrote:

> I=92m implementing an UART for a 21161n DSP as it=92s shown on the EE-191=
 Analog Device=92s document.
>
> http://www.analog.com/UploadedFiles/Application_Notes/399447663EE191.pdf
>
> According to the schematic two flag pins can be optionally connected to m=
anage the CTS and RTS control signals.
>
> Could anybody explain me where may I connect them (what FLAGx and FLAGy a=
re?) and what=92s their utility?

Any flag pins will work, so pick the most convienient.  CTS is input, RTS
is output.  When CTS is low, stop sending data, when CTS is high you can
send.  Pull RTS low when you want the other side to stop sending you data.
A search on RS232 protocol will explain it.

Note that "low" and "high" are logic not voltage level.  Life can get
really confusing because the full standard is based on +/- 10V signals
and lots of logic translators call -10V =3D +TTL and +10V =3D GND.  But not
all of them :-)  Good luck!

Patience, persistence, truth,
Dr. mike

=20