Printronix P9000 Series, User'S Reference Manual

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7-5 Interfaces
Centronics Parallel Interface Configuration
The printer is configured according to the interface specified during printer configuration (reĆ
fer to the Configuration chapter). If, however, the interface configuration parameters need to
be changed, printer configuration is also user selectable. The following configuration parameĆ
ters can be verified or changed as necessary to meet specific application requirements:
n
Input Buffer Size (Selected from the Application Compatibility Menu)
n
Data Bit 8 (Enable or Disable)
n
PI Line (Enable or Disable)
n
Data Polarity (standard or inverted)
n
Response Polarity (standard or inverted)
n
Latch Data On Leading or Trailing Edge of Strobe
n
Fast Busy (Enable or Disable)
These parameters are displayed under the Application Compatibility/Host Interface/
Centronics submenu selectable from the control panel. Refer to the Control Panel ConfiguraĆ
tion Diagram in the Configuration chapter for information on selecting the various parameter
values.
Alternate Terminating Resistors
For parallel interface configurations, the printer is equipped with 470 ohm pullup and 1K
pulldown terminating resistors located at board coordinates 5V and 4V respectively, on the
DCU PCBA 132015. Generally, these terminating resistors are suitable for most applications.
If, however, the standard terminating resistor pack is not compatible with the particular interĆ
face driver requirements of the host, other values of pullup/pulldown resistors may be necesĆ
sary. Printronix provides the 220 ohm pullup and 330 ohm pulldown alternate terminating
resistors. If the 220 ohm pullup resistor is used, the 330 ohm pulldown resistor should be used
with it.
To install the alternate terminating resistors, perform the following steps.
1.
Turn the printer off and disconnect the AC power cord.
2. Remove the DCU PCBA as described in Appendix F, Hardware Jumper Configuration.
3. Remove the 470 ohm resistor pack from the socket at location 5V.
4. Plug the 220 ohm resistor pack into the socket at location 5V.
5. Remove the 1K ohm resistor pack from the socket at location 4V.
6. Plug the 330 ohm resistor pack into the socket at 4V.
7. Re-install the DCU PCBA as described in Appendix F, Hardware Jumper ConfiguraĆ
tion.
8. Reconnect the AC power cord and turn the printer on.
RS-232 Serial Interface
This interface is used with bit serial devices compatible with EIA- RS-232C or CCITT V.24
standards. The serial data transfer baud rate is selectable from the control panel. Baud rates of