Sun Microsystems SunSAI/P, User Manual

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10 SunSAI/P User’s Guide • November 1998
To connect the SunSAI/P board to a modem, use a standard “straight-through” cable
(
FIGURE 4-1
) to connect the modem to one of the DB-25 connectors on the connector
box.
Note –
Shielded cable must be used to remain in compliance with Part 15 of FCC
rules.
Connecting to a DTE Device
A DTE device is a terminal, serial printer, another computer's serial port, etc. To
connect the SunSAI/P board (which is also a DTE device) to another DTE device,
you need a null modem cable or adapter.
Software Handshaking (XON/XOFF)
In most cases, serial terminals and printers need only a “three-wire” connection to
the SunSAI/P board. The Solaris device driver supports XON/XOFF (software)
handshaking, so the only signal lines necessary are Transmitted Data (TxD),
Received Data (RxD) and Signal Ground (SG). Cables must be shielded to remain in
compliance with FCC certification requirements, and the shield should be connected
to Chassis Ground (GND) at both ends of the cable run.
A simple cable for connecting a terminal or a printer to a DB-25 equipped SunSAI/P
board is shown below.