Centronics Parallel Interface; Centronics Interface Signals - Printronix P3000 Series User's Reference Manual

Strobe Polarity (standard or inverted)
Latch Data On Leading or Trailing Edge of Strobe
These parameters are displayed under the Application Compatibility/Host Interface/Dataproducts
submenu from the control panel. Refer to Control Panel Configuration Diagram in the Configuration
chapter for information on selecting the various parameter values.
Based on the application, a unique configuration may be required. If the printer is not working properly
for the configuration selected, contact your authorized service representative.
NOTE: The PI line must be disabled from the control panel if the host computer does not
drive or control the PI line. If the line is not controlled by the host and sensing is enabled,
rapid paper slewing will occur.

Centronics Parallel Interface

This interface enables the printer to operate with controllers designed for buffered Centronics printers.
The maximum data line length (cable length) from the controller (host computer) to the printer is 40
feet.

Centronics Interface Signals

Table 7–2 lists the Centronics interface connector pin assignments. Centronics interface signals be-
tween the computer and the printer are defined as follows.
PE – A high true level from the printer indicating the printer is in a check condition.
SLCT – A high true level from the printer indicating the printer is ready for data transfer and the ON
LINE switch has been activated.
Busy – A high true level from the printer indicating the printer cannot receive data.
ACKNLG – A low true pulse from the printer indicating the character or function code has been re-
ceived and the printer is ready for the next data transfer.
Data Strobe – A low true, 100 ns min. pulse from the host to clock data into the printer.
Data Lines – Eight standard or inverted levels from the host that specify a character or function code.
Sensing Data Line 8 is controlled by printer configuration.
Paper Instruction (PI) – Optional EVFU or DVFU control signal from the host with the same timing
as the data lines. Sensing the PI line is controlled by printer configuration.
NOTE: The PI line must be disabled from the control panel if the host computer does not
drive or control the PI line. If the line is not controlled by the host and sensing is enabled,
rapid paper slewing will occur.
Interfaces 7–3