SCC(3) SCC(3)
NAME
scc, duart, uart - serial communication control
SYNOPSIS
bind -a #t /dev
/dev/eia0
/dev/eia0ctl
/dev/eia1
/dev/eia1ctl
DESCRIPTION
The serial line devices serve a one-level directory, giving
access to the serial ports. There are several devices serv-
ing the same files; the particular one used depends on the
machine involved. Eia0 is a stream data file. It can be
read and written to use that port. Reads will block until
at least one character is available. Eia0ctl is a stream
control file associated with the port. Eia1 and eia1ctl are
similar, but for a second serial line.
The ctl file can be used to push stream modules onto the
port. One can also write one of the following textual com-
mands to a ctl file:
bn Set the baud rate to n.
dn Set DTR if n is non-zero; else clear it.
kn Send a break lasting n milliseconds.
rn Set RTS if n is non-zero; else clear it.
mn Obey modem CTS signal if n is non-zero; else clear it.
pc Set parity to odd if c is o, to even if c is e; else
set no parity.
sn Set number of stop bits to n. Legal values are 1 or 2.
ln Set number of bits per byte to n. Legal values are 5,
6, 7, or 8.
SOURCE
/sys/src/9/port/devscc.c
/sys/src/9/*/devduart.c
/sys/src/9/*/devuart.c
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