se - Siemens 82532 ESCC serial communications driver
The se module is a loadable STREAMS driver that provides
basic support for the 82532 ESCC hardware and basic asyn-
chronous and synchronous communication support. This manual
page describes the asynchronous protocol interface; for
information on the synchronous interface, please see the
se_hdlc(7D) manual page.
This module is affected by the setting of specific
eeprom variables. For information on parameters that
are persistent across reboots, see the eeprom(1M) man
The platform specific device bus address for the se module
is bus_address. The se module's port_name is a single letter
During boot up, ttya/b characteristics are read from
the /kernel/drv/options.conf file and changed from the
PROM defaults to reflect Solaris defaults. Messages
displayed on the console after this point are based on
settings in that file. If you switch a characteristic,
(for example, the baud rate of the console terminal),
you must revise the /kernel/drv/options.conf or the
console will be configured to an unusable configuration
and console messages will be garbled by the mismatched
serial port settings.
APPLICATION PROGRAMMING INTERFACE
The Siemens 82532 provides two serial input/output channels
capable of supporting a variety of communication protocols.
A typical system will use one of these devices to implement
two serial ports (port_name), usually configured for RS-423
(which also supports most RS-232 equipment). The Siemens
82532 uses 64 character input and output FIFOs to reduce
system overhead. When receiving characters, the CPU is noti-
fied when 32 characters have arrived (one-half of receive
buffer is full) or no character has arrived in the time it
would take to receive four characters at the current baud
When sending characters, the Siemens 82532 places the first
64 characters to be sent into its output FIFO and then noti-
fies the CPU when it is half empty (32 characters left).
Because the se module waits for the Siemens 82532 to
transmit the remaining characters within its output FIFO
before making requested changes, delays may occur when the
port's attributes are being modified.
The se module implements CTS/RTS flow control in hardware.
To prevent data overruns, remove CTS/RTS flow control
responsibility from the CPU during periods of high system
In async mode (obtained by opening /dev/cua/[a-z],
/dev/term/[a-z] or /dev/tty[a-z]), the driver supports the
termio(7I) device control functions specified by flags in
the c_cflag word of the termios structure, and by the
IGNBRK, IGNPAR, PARMRK, or INPCK flags in the c_iflag word.
All other termio(7I) functions must be performed by STREAMS
modules pushed atop the driver. When a device is opened,
the ldterm(7M) and ttcompat(7M) STREAMS modules are automat-
ically pushed on top of the stream, providing the standard
Each of the following are valid name space entries:
/dev/cua/[a-z], /dev/term/[a-z], and /dev/tty[a-z]. The
number of entries used in this name space are machine depen-
dent. The /dev/tty[a-z] device names exist only if the SunOS
4.x Binary Compatibility Package is installed. The
/dev/tty[a-z] device names are created by the ucblinks com-
mand, which is available only with the SunOS 4.x Binary Com-
You can connect a single tty line to a modem for incoming
and outgoing calls using a special feature controlled by the
minor device number. By accessing character-special devices
with names of the form /dev/cua/[a-z], it is possible to
open a port without the Carrier Detect signal being
asserted, either through hardware or an equivalent software
mechanism. These devices are commonly known as dial-out
After a /dev/cua/[a-z] line is opened, the corresponding tty
line cannot be opened until the /dev/cua/[a-z] line is
closed. A blocking open will wait until the /dev/cua/[a-z]
line is closed (which will drop Data Terminal Ready and Car-
rier Detect) and carrier is detected again. A non-blocking
open will return an error. If the tty line has been opened
successfully (usually only when carrier is recognized on the
modem), the corresponding /dev/cua/[a-z] line cannot be
opened. This allows a modem to be attached to a device,
(for example, /dev/term/ [a-z] renamed from /dev/tty[a-z])
and used for dial-in (by enabling the line for login in
/etc/inittab) and dial-out (by tip(1) or uucp(1C)) as
/dev/cua/[a-z] when no one is logged in on the line.
The se module supports the standard set of termio ioctl()
Breaks can be generated by the TCSBRK, TIOCSBRK, and
TIOCCBRK ioctl() calls.
The state of the DCD, CTS, RTS, and DTR interface signals
can be queried through the use of the TIOCM_CAR, TIOCM_CTS,
TIOCM_RTS, and TIOCM_DTR arguments to the TIOCMGET ioctl
command, respectively. Due to hardware limitations, only
the RTS and DTR signals may be set through their respective
arguments to the TIOCMSET, TIOCMBIS, and TIOCMBIC ioctl com-
The input and output line speeds may be set to all baud
rates supported by termio. Input and output line speeds can-
not be set independently; when you set the output speed, the
input speed is automatically set to the same speed.
When using baud rates over 100,000 baud, the software
changes the line driver configuration to handle the higher
data rates. This action decreases the theoretical maximum
cable length from 70 meters to 30 meters.
When the se module is used to service the serial console
port, it supports a BREAK condition that allows the system
to enter the debugger or the monitor. The BREAK condition is
generated by hardware and it is usually enabled by default.
A BREAK condition originating from erroneous electrical sig-
nals cannot be distinguished from one deliberately sent by
remote DCE. Due to the risk of incorrect sequence interpre-
tation, binary protocols such as PPP, SLIP and others should
not be run over the serial console port when the Alternate
Break sequence is in effect. By default, the Alternate Break
sequence is a three character sequence: carriage return,
tilde and control-B (CR ~ CTRL-B), but may be changed by the
driver. For information on breaking (entering the debugger
or monitor), see kadb(1) and kb(7M.)
An open() will fail under the following conditions:
ENXIO The unit being opened does not exist.
EBUSY The dial-out device is being opened and the
dial-in device is already open, or the dial-in
device is being opened with a no-delay open and
the dial-out device is already open.
EBUSY The port is in use by another serial protocol.
EBUSY The unit has been marked as exclusive-use by
another process with a TIOCEXCL ioctl() call.
EINTR The open was interrupted by the delivery of a
dial-out tty lines
dial-in tty lines
binary compatibility package device names
synchronous devices - see se_hdlc(7D).
synchronous control clone device
System wide default device driver properties
See attributes(5) for descriptions of the following attri-
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
| Architecture | SPARC |
tip(1), kadb(1), ucblinks(1B), cu(1C), uucp(1C), eeprom(1M),
ports(1M), ioctl(2), open(2), attributes(5),zs(7D), zsh(7D),
se_hdlc(7D), termio(7I), ldterm(7M), ttcompat(7M), kb(7M)
sen : fifo overrun
The Siemens 82532 internal
FIFO received more data than it could handle. This
indicates that Solaris was not servicing data inter-
rupts fast enough and suggests a system with too many
interrupts or a data line with a data rate that is too
sen : buffer overrun
The se module was unable to store data it removed
from the Siemens 82532 FIFO. The user process is not
reading data fast enough, and suggests an overloaded
system. If possible, the application should enable
flow control (either CTSRTS or XONXOFF) to allow the
driver to backpressure the remote system when the
local buffers fill up.
Man(1) output converted with