Re: How to avoid serial port buffer overruns?

From: Robert Hancock
Date: Wed Aug 16 2006 - 10:33:16 EST

Raphael Hertzog wrote:
(Please CC me when replying)


While using Linux on low-end (semi-embedded) hardware (386 SX 40Mhz, 8Mb
RAM), I discovered that Linux on that machine would suffer from serial
port buffer overruns quite easily if I use a baudrate high enough (I start
loosing bytes at >19200 bauds and I would like to make it reliable up to 115 kbauds). I check if overruns are happening with
/proc/tty/driver/serial ("oe" field).

What kind of serial port are you using? If it's an unbuffered 8250-type port, it will NEVER be reliable at higher baud rates. You want a 16550 (or better) port.

Robert Hancock Saskatoon, SK, Canada
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