NetWare 4.1/9000 Print Services

B-8
Cabling Printers
Optimal Serial Cabling
Optimal Serial Cabling
This section explains how Hewlett-Packard uses RS-232-C serial
communication for printing.
NOTE: Anyone making changes to their cabling pin configurations should be familiar with
soldering techniques and with tracing wires using a multimeter or color-coding.
Serial printers cabled to PCs generally use the RS-232-C interface, which
was developed specifically for terminal-to-modem communications, or
communication between Data Terminal Equipment (DTE) and Data
Communications Equipment (DCE). Proper handshaking, the exchange of
signals to control the flow of data between hardware devices, allows data to
flow correctly between DTE and DCE devices.
Since PCs and printer are both DTE, they must send signals as DTE.
However, they must be cabled so that they receive signals as if from DCE.
Because PC and printer vendors implement this serial handshaking in
different ways, many problems occur when the signals are not correctly
routed between them.
The following chart shows optimal cabling between 9 and 25-pin PC
connectors and a 25-pin printer connector for NetWare print services. Each
pin handles certain functionality, as explained in the following sections.