freebsd-src/share/man/man4/si.4

.\" $Id: si.4,v 1.4 1996/02/12 01:20:36 mpp Exp $
.\" The following requests are required for all man pages.
.Dd September 16, 1995
.Os FreeBSD
.Dt SI 4
.Sh NAME
.Nm si
.Nd Driver for Specialix International SI/XIO 8-32 port intelligent serial card.
.Sh SYNOPSIS
.Nm "device si0 at isa? tty irq 12 iomem 0xd0000 vector siintr"
.Sh DESCRIPTION
The Specialix SI and XIO hardware makes up an 8 to 32 port RS-232 serial
multiplexor.
.Pp
This driver was ported and tested on an ISA bus machine, and has rudimentry
support for operation on an EISA bus system as well, but as of this time the
EISA version has not been tested by the Author - it may or may not work.  It
has yet to be updated to the 'new style' eisa configuration system.
.Pp
The system uses two components..  A "Host adapter", which is plugged into
an ISA/EISA slot and provides intelligence and buffering/processing
capabilities, as well as an external bus in the form of a 50 pin cable.
.Pp
On this cable, "modules" are connected.  The "SI" module comes in a 4 and 8
port version, and has simple UARTS.  The "XIO" module comes only in an 8 port
version, and has two powerful RISC-like UARTS as well.
.Pp
The host adapter polls and transfers data between the modules and the main
Operating system.  The Host adapter provides a 256 byte transmit and 256 byte
receive FIFO for each of the 32 ports that it can maintain.
.Pp
The XIO module panels can operate each of their 8 ports at 115,200 baud, while
the SI version can run at 57,600 baud.
.Pp
The host adapter uses a shared memory block in the traditional ISA bus
"hole" betweem 0xA0000 and 0xEFFFF.  The adapter can be configured outside
range, but requires the memory range to be explicitly non-cached.  The
driver does not yet support this mode of operation.
.Pp
The adapter can use Irq's 11, 12 or 15.  It is rumoured that the ISA adapter
cards provide their own tri-state drivers and pullups, and may be able to
share an IRQ between all SI/XIO host cards.  This has not been tested, and
the driver does not support this mode of operation.  The actual IRQ used is 
soft-configured onto the host card at boot time, but automatic selection
of a free IRQ is not yet implemented in the FreeBSD version.
.Pp
The si device driver may have some of it's configuration settings changed
at run-time with the
.Xr sicontrol 8
utility.
.Pp
The si device driver also responds to the
.Xr comcontrol 8
utility for configuring drain-on-close timeouts.
.Pp
An open on a /dev device node controlled by the si driver obeys the same
semantics as the
.Xr sio 4
driver.  It fully supports the usual semantics of the cua ports, and the
"initial termios" and "locked termios" settings.  In summary, an open on a
tty port will block until DCD is raised, unless O_NONBLOCK is specified.
CLOCAL is honored.  An open on a cua port will always succeed, but DCD
transitions will be honored after DCD rises for the first time.
.Pp
Normally, up to four SI/XIO host cards may be controlled by the si driver,
but due to the lack of available interrupts that the card can be configured
to use, only three may be presently used.  Polling operation is not currently
implemented, although it is a standard mode of operation for Specialix shipped
drivers.  Once this is implemented, all four cards may be used.
.Pp
The lowest 5 bits of the minor device number are used to select the port
number on the mudule cluster.
si driver,
but due to the lack of available interrupts that the card can be configured
to use, only three may be presently used.  Polling operation is not currently
implemented, although it is a standard mode of operation for Specialix shipped
drivers.  Once this is implemented, all four cards may be used.
.Pp
The lowest 5 bits of the minor device number are used to select the port
number on the mudule cluster. The next 2 bits select which of 4 host adapter
cards.  This allows a maximum of 128 ports on this driver.
.Pp
Bit 7 is used to differentiate a tty/dialin port (bit 7=0) and a
cua/callout port (bit 7=1).
.Pp
Bit 8 through 15 (on FreeBSD) are unavailable as they are a shadow of the
major device number.
.Pp
If bit 16 is a 1, the device node is referring to the "initial state" device.
This "initial state" is used to prime the
.Xr termios 4
settings of the device when it is initially opened.
If bit 17 is a 1, the device node is referring to the "locked state" device.
The "locked state" is used to prevent the
.Xr termios 4
settings from being changed.
.Pp
To manipulate the initial/locked settings, the 
.Xr stty 1
command is useful.  When setting the "locked" variables, enabling the mode
on the lock device will lock the termios mode, while disabling the mode will
unlock it.
.\" The following requests should be uncommented and used where appropriate.
.\" This next request is for sections 2 and 3 function return values only.
.\" .Sh RETURN VALUES
.\" This next request is for sections 1, 6, 7 & 8 only
.\" .Sh ENVIRONMENT
.Sh FILES
.Bl -tag -width /dev/si_control -compact
.It Pa /dev/si_control
global driver control file for
.Xr sicontrol 8
.It Pa /dev/ttyA*
terminal/dialin ports
.It Pa /dev/cuaA*
dialout ports
.It Pa /dev/ttyiA*
initial termios state devices
.It Pa /dev/ttylA*
locked termios state devices
.El
.\" .Sh EXAMPLES
.\" This next request is for sections 1, 6, 7 & 8 only
.\"     (command return values (to shell) and fprintf/stderr type diagnostics)
.\" .Sh DIAGNOSTICS
.\" The next request is for sections 2 and 3 error and signal handling only.
.\" .Sh ERRORS
.Sh SEE ALSO
.Xr stty 1 ,
.Xr sio 4 ,
.Xr termios 4 ,
.Xr tty 4 ,
.Xr comcontrol 8 ,
.Xr sicontrol 8
.\" .Sh STANDARDS
.Sh HISTORY
This driver is loosely based on driver code originating at Specialix, which
was ported to run on BSDI by
.Nm Andy Rutter <andy@specialix.co.uk> .
The System V driver source is/was available by ftp from
.Nm ftp.specialix.co.uk .
.Pp
This driver is not supported by Specialix International. 
.Sh AUTHORS
.Nm Peter Wemm <peter@freebsd.org>
obtained the code from Andy Rutter and ported it to FreeBSD, with a large
amount of invalueable assistance from
.Nm Bruce Evans <bde@zeta.org.au>
.Pp
Man page by Peter Wemm.
.Sh BUGS
The EISA support is untested.
.Pp
The interrupt tuning rate is not believed to be optimal at this time for
maximum efficiency.
.Pp
POLL mode is not implemented yet.
.Pp
Operation outside the traditional ISA "hole" is not yet supported, although it
should work if the test is removed from the probe routine.