NetWare 4.1/9000 Print Services

B-11
Cabling Printers
Optimal Serial Cabling
NetWare print services does not use this pin. Other print services may require a
high signal level for both Pins 5 and 6 on the PC for proper data flow control.
Hewlett-Packard recommends that you tie (solder) Pins 5 and 6 together to
provide printing compatibility for other print services.
7 SG (Signal Ground reference pin)
NetWare print services uses this pin to provide a reference for signal levels. The
PC uses Pin 5 on a 9-pin connector and Pin 7 on a 25-pin connector. The printer
uses Pin 7.
8 DCD (Data Carrier Detect input pin)
Some PCs may require a high signal level on this pin to enable the PC to receive
data from the printer. The XON/XOFF protocol will not function correctly with
a low signal level. If you do not use the XON/XOFF protocol, the signal level on
this pin can be high or low. The PC uses Pin 1 on a 9-pin connector and Pin 8 on
a 25-pin connector.
Hewlett-Packard recommends that you maintain a high signal level on this pin
by tying (soldering) it to another pin that has a high signal level. Tie Pin 1 on a
9-pin connector to either Pin 7 or Pin 4. Tie Pin 8 on a 25-pin connector to Pin 4
or Pin 20.
9 DTR (Data Terminal Ready output pin)
NetWare print services sets the signal level high for this pin (and the RTS pin)
on the PC and keeps it in that state. The PC uses Pin 4 on a 9-pin connector and
Pin 20 on a 25-pin connector. This signal can be used as a source for a high
signal level to enable certain functions on some printers. If your printer cable
connects this pin to a pin on the printer that requires a high signal level, printing
will function properly. You can achieve the same results by following the steps
in note 12.
NOTE: Early versions of NetWare print services set the signal level high on this pin when
sending data and set the signal level low when not sending data. The timing of the
signal changes caused many problems with printers that require a high signal level
for data input. Beginning with version 1.22R, NetWare Print Services constantly
maintains a high signal level for this pin.
Functions on the Printer Side of Serial Printer Cables
1 TXD (Transmit Data output pin)