75 lines
3.0 KiB
HTML
75 lines
3.0 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
|
|
<HTML>
|
|
<HEAD>
|
|
<META NAME="GENERATOR" CONTENT="LinuxDoc-Tools 0.9.21">
|
|
<TITLE> Serial HOWTO: Configuring the Serial Driver (high-level) "stty"</TITLE>
|
|
<LINK HREF="Serial-HOWTO-10.html" REL=next>
|
|
<LINK HREF="Serial-HOWTO-8.html" REL=previous>
|
|
<LINK HREF="Serial-HOWTO.html#toc9" REL=contents>
|
|
</HEAD>
|
|
<BODY>
|
|
<A HREF="Serial-HOWTO-10.html">Next</A>
|
|
<A HREF="Serial-HOWTO-8.html">Previous</A>
|
|
<A HREF="Serial-HOWTO.html#toc9">Contents</A>
|
|
<HR>
|
|
<H2><A NAME="config_stty"></A> <A NAME="s9">9.</A> <A HREF="Serial-HOWTO.html#toc9">Configuring the Serial Driver (high-level) "stty"</A></H2>
|
|
|
|
<H2><A NAME="ss9.1">9.1</A> <A HREF="Serial-HOWTO.html#toc9.1">Overview</A>
|
|
</H2>
|
|
|
|
<P>See the section
|
|
<A HREF="Serial-HOWTO-11.html#stty_">Stty</A>. The "stty" command
|
|
sets many things such as flow control, speed, and parity. The only
|
|
one discussed in this section is flow control.</P>
|
|
|
|
<H2><A NAME="ss9.2">9.2</A> <A HREF="Serial-HOWTO.html#toc9.2">Flow Control</A>
|
|
</H2>
|
|
|
|
<P> Configuring Flow Control: Hardware Flow Control is Usually Best
|
|
See
|
|
<A HREF="Serial-HOWTO-4.html#flow_control">Flow Control</A> for an explanation of
|
|
it. It's usually better to use hardware flow control rather than
|
|
software flow control using Xon/Xoff. To use full hardware flow
|
|
control you must normally have two dedicated wires for it in the cable
|
|
between the serial port and the device. If the device is on a card or
|
|
the motherboard, then it should always be possible to use hardware
|
|
flow control.</P>
|
|
<P>Many applications (and the getty program) give you an option
|
|
regarding flow control and will set it as you specify or it might
|
|
enable hardware flow control by default if you don't set it. It must
|
|
be set both in the serial driver and in the hardware connected to the
|
|
serial port. How it's set into this hardware is hardware dependent.
|
|
Sometimes there is a certain "init string" you send to the hardware
|
|
device via the serial port from your PC. For a modem, the
|
|
communication program should set it in both places.</P>
|
|
<P>If a program you use doesn't set flow control in the serial driver,
|
|
then you may do it yourself using the <CODE>stty</CODE> command. Since the
|
|
driver doesn't remember the setting after you stop Linux, you could
|
|
put the stty command in a file that runs at start-up or when you login
|
|
(such as /etc/profile for the bash shell). Here's what you would add
|
|
for hardware flow control for port ttyS2:</P>
|
|
<P>
|
|
<BLOCKQUOTE><CODE>
|
|
<PRE>
|
|
stty -F /dev/ttyS2 crtscts
|
|
</PRE>
|
|
</CODE></BLOCKQUOTE>
|
|
|
|
or for old stty versions < 1.17:
|
|
<BLOCKQUOTE><CODE>
|
|
<PRE>
|
|
stty crtscts < /dev/ttyS2
|
|
</PRE>
|
|
</CODE></BLOCKQUOTE>
|
|
</P>
|
|
<P><CODE>crtscts</CODE> stands for a Control setting to use the RTS and CTS pins of
|
|
the serial port for hardware flow control. Note that RTS+CTS almost
|
|
spells: <CODE>crtscts</CODE> and the initial "c" means "control".</P>
|
|
|
|
<HR>
|
|
<A HREF="Serial-HOWTO-10.html">Next</A>
|
|
<A HREF="Serial-HOWTO-8.html">Previous</A>
|
|
<A HREF="Serial-HOWTO.html#toc9">Contents</A>
|
|
</BODY>
|
|
</HTML>
|