Connecting A Modem To The Sun-3/260 - Sun Microsystems Sun-3/260 Hardware Installation Manual

NOTE
Connecting a fvlodem to the
Sun-3/260
Cunnecting a Terminal to the
Sun-3/260
Chapter 2 - Basic Component Set-up
29
their RS-232-C counterparts. However the Sun-3/260 uses improved electrical
circuits which, while working with RS-232-C devices, are also compatible with
the newer RS-423 standard.
The serial ports on the Sun-3/260 were designed for connecting to peripherals
such as printers and plotters, and can drive these output lines at speeds up to 19.2
kilobaud; input lines may be driven to 9600 baud. When the system has been
booted with the DIAG/NORM switch set in the NORM position, the default serial
port baud rate is 9600. For more information please see Installing UNIX on the
Sun
~Vorkstation,
part number 800-1521-XX. Reference the appendix on The
PROM
IY[onitor and the
EEPROM.
All ports provide DTR, RTS, and clock signals, and receive DSR, CTS, and DCD
signals. All ports are wired as Data Terminal Equipment (DTE) ports (which
means Transmit Data from the workstation is on pin 2 and Receive Data from the
peripheral is on pin 3), and thus allow direct connection of Data Communications
Equipment (DCE) such as modems. Computers, terminals, printers, and other
DTE devices can also be connected directly to the serial ports by using the null
modem cable available from Sun, part number 530-1056-XX. For further infor-
mation refer to System Inter/ace lv!anual for the Sun Workstation, part number
800-1303-XX, section ZS( 4S), which discusses the Zilog serial interface.
Signals carried on the SERIAL PORT A and SERIAL PORT B connectors are listed
in the appendix.
Thefollowing sections-which describe connecting modems, terminals, and
printers to the serial pons-are guidelines only, and specific devices may
require more detailed information such as that contained in the System Interface
manual.
The serial pons are wired as DTEs, and most modems are wired
as
DCEs. The
cable connecting your modem to the Sun-3/260 should be
~'straight
through" -
the signals on pins 2, 3,4,5, 6, 7, 8, and 20 at the output of the cable should be
the same as those signals on corresponding pins of the serial port. Do not use a
null modem cable to connect
the
serial pall to your modem.
It
does not matter
which serial port you connect to; both are identical.
Refer to the manual which comes with your modem to see which signals you
will
need for proper operation
of your modem. Refer also to System Administration
for the Sun
~Vorksrarion,
part number
800-1323-~"X,
and Installing UNIX on the
SUIl
~Vorksta;ion,
part number 8CQ-1521-XX, \vhich detail connecting to a
modem.
The serial ports
are
wired
as
OTEs. 1\;1ost terminals
are
wired
as
DTEs too. To
connect
1
terminal to
a
serial port
you
must first make certain that the tenninai
you are using accepts the RS-Z31-C or RS-423 protocol. Ii it does, you may t.i-}en
connect the tenninal to eithe: serial port with a null modem cable, Sun pan
number 530-1056-XX. In the null modem cable, pins
2 and 3 are cro:)sed
~Slln
~""
microsyMsms
Revision A of 10 OctDbcr 1986