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If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner] .TH su 7D "18 June 2004" "SunOS 5.11" "Devices" .SH NAME su \- asynchronous serial port driver .SH SYNOPSIS .LP .nf #include #include open("/dev/tty\fI[a-z]\fR", _\fImode\fR); open("/dev/term\fI[a-z]\fR", _\fImode\fR); open("/dev/cua\fI[a-z]\fR", _\fImode\fR); .fi .LP .nf .fi .SH DESCRIPTION .sp .LP The \fBsu\fR module is a loadable STREAMS driver that provides basic support for standard \fBUARTS\fR that use Intel-8250, National Semiconductor-16450/16550 hardware and Southbridge 1535D (16550 compatable) Super I/O hardware. The module also provides keyboard and mouse I/O support for Sun machines using those same Intel, National Semiconductor and Southbridge chipsets. The \fBsu\fR driver provides basic asynchronous communication support for serial ports. Both the serial devices and keyboard/mouse devices will have streams built with appropriate modules pushed atop the \fBsu\fR driver by means of either the \fBautopush\fR(1M) or \fBdacf.conf\fR(4) facilities, depending on the OS revision and architecture in use. .sp .LP The \fBsu\fR module supports those \fBtermio\fR(7I) device control functions specified by flags in the \fBc_cflag\fR word of the \fBtermios\fR structure, and by the \fBIGNBRK,\fR \fBIGNPAR,\fR \fBPARMRK,\fR or \fBINPCK\fR flags in the \fBc_iflag\fR word of the \fBtermios\fR structure. All other \fBtermio\fR(7I) functions must be performed by \fBSTREAMS\fR modules pushed atop the driver. When a device is opened, the \fBldterm\fR(7M) and \fBttcompat\fR(7M) \fBSTREAMS\fR modules are automatically pushed on top of the stream, providing the standard \fBtermio\fR(7I) interface. .sp .LP The character-special devices \fB/dev/ttya\fR and \fB/dev/ttyb\fR are used to access the two standard serial ports. The \fBsu\fR module supports up to ten serial ports, including the standard ports. The \fBtty\fR\fI[a-z]\fR devices have minor device numbers in the range 00-03, and may be assigned names of the form \fB/dev/ttyd_\fR\fIn_,\fR where \fI_n_\fR denotes the line to be accessed. These device names are typically used to provide a logical access point for a \fI_dial-in_\fR line that is used with a modem. .sp .LP To allow a single tty line to be connected to a modem and used for incoming and outgoing calls, a special feature is available that is controlled by the minor device number. By accessing character-special devices with names of the form \fB/dev/cua\fR\fI_n, \fR it is possible to open a port without the \fBCarrier Detect\fR signal being asserted, either through hardware or an equivalent software mechanism. These devices are commonly known as \fI_dial-out_\fR lines. .SH APPLICATION PROGRAMMING INTERFACE .sp .LP Once a \fB/dev/cua\fR\fI_n_\fR line is opened, the corresponding tty, or ttyd line cannot be opened until the \fB/dev/cua\fR\fI_n_\fR line is closed. A blocking open will wait until the \fB/dev/cua\fR\fI_n_\fR line is closed (which will drop \fBData Terminal Ready\fR, after which \fBCarrier Detect\fR will usually drop as well) and carrier is detected again. A non-blocking open will return an error. If the \fB/dev/ttyd\fR\fI_n_\fR line has been opened successfully (usually only when carrier is recognized on the modem), the corresponding \fB/dev/cua\fR\fI_n_\fR line cannot be opened. This allows a modem to be attached to a device, (for example, \fB/dev/ttyd0\fR, which is renamed from \fB/dev/tty00\fR) and used for dial-in (by enabling the line for login in \fB/etc/inittab\fR) or dial-out (by \fBtip\fR(1) or \fBuucp\fR(1C)) as \fB/dev/cua0\fR when no one is logged in on the line. .SH IOCTLS .sp .LP The standard set of \fBtermio\fR \fBioctl()\fR calls are supported by \fBsu\fR. .sp .LP Breaks can be generated by the \fBTCSBRK,\fR \fBTIOCSBRK,\fR and \fBTIOCCBRK\fR \fBioctl()\fR calls. .sp .LP The input and output line speeds may be set to any of the following baud rates: 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800, 9600, 19200, 38400, 57600 or 115200. The speeds cannot be set independently; for example, when the output speed is set, the input speed is automatically set to the same speed. .sp .LP When the \fBsu\fR 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. .sp .LP A BREAK condition originating from erroneous electrical signals cannot be distinguished from one deliberately sent by remote DCE. The Alternate Break sequence can be used as a remedy against this. Due to a risk of incorrect sequence interpretation, SLIP and certain other binary protocols should not be run over the serial console port when Alternate Break sequence is in effect. Although PPP is a binary protocol, it is able to avoid these sequences using the ACCM feature in \fIRFC 1662\fR. For Solaris PPP 4.0, you do this by adding the following line to the \fB/etc/ppp/options\fR file (or other configuration files used for the connection; see \fBpppd\fR(1M) for details): .sp .in +2 .nf asyncmap 0x00002000 .fi .in -2 .sp .LP 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 more information on breaking (entering the debugger or monitor), see \fBkbd\fR(1) and \fBkb\fR(7M). .SH ERRORS .sp .LP An \fBopen()\fR will fail under the following conditions: .sp .ne 2 .mk .na \fB\fBENXIO\fR\fR .ad .RS 9n .rt The unit being opened does not exist. .RE .sp .ne 2 .mk .na \fB\fBEBUSY\fR\fR .ad .RS 9n .rt The dial-out device is being opened while 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. .RE .sp .ne 2 .mk .na \fB\fBEBUSY\fR\fR .ad .RS 9n .rt The unit has been marked as exclusive-use by another process with a \fBTIOCEXCL\fR \fBioctl()\fR call. .RE .SH FILES .sp .ne 2 .mk .na \fB\fB/dev/cua/[a-z]\fR\fR .ad .RS 19n .rt dial-out tty lines .RE .sp .ne 2 .mk .na \fB\fB/dev/term/[a-z]\fR\fR .ad .RS 19n .rt dial-in tty lines .RE .sp .ne 2 .mk .na \fB\fB/dev/tty[a-z]\fR\fR .ad .RS 19n .rt binary compatibility package device names .RE .SH ATTRIBUTES .sp .LP See \fBattributes\fR(5) for descriptions of the following attributes: .sp .sp .TS tab() box; cw(2.75i) |cw(2.75i) lw(2.75i) |lw(2.75i) . ATTRIBUTE TYPEATTRIBUTE VALUE _ Architecture SPARC .TE .SH SEE ALSO .sp .LP \fBstrconf\fR(1), \fBkbd\fR(1), \fBtip\fR(1),\fBuucp\fR(1C), \fBautopush\fR(1M), \fBkstat\fR(1M), \fBpppd\fR(1M), \fBioctl\fR(2), \fBopen\fR(2), \fBtermios\fR(3C), \fBdacf.conf\fR(4), \fBattributes\fR(5), \fBkb\fR(7M), \fBldterm\fR(7M), \fBttcompat\fR(7M), \fBtermio\fR(7I) .SH DIAGNOSTICS .sp .LP The \fBsu\fR driver keeps track of various warning and error conditions using \fBkstat\fR counters. The output of the \fBkstat su\fR command provides \fBkstat\fR counters. The counters and their meaning follow: .sp .ne 2 .mk .na \fBsilo overflow\fR .ad .RS 24n .rt The internal chip FIFO received more data than it could handle. This indicates that the Solaris operating environment was not servicing data interrupts fast enough possibly due to a system with too many interrupts or a data line with a data rate that is too high. .RE .sp .ne 2 .mk .na \fBring buffer overflow\fR .ad .RS 24n .rt The \fBsu\fR module was unable to store data it removed from the chips internal FIFO into a software buffer. The user process is not reading data fast enough, possibly due to 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. .RE