Centronics Parallel Interface Signals - Printronix L5035 User Manual

Centronics Parallel Interface Signals

The Centronics interface signals are defined below.
PAPER EMPTY (PE) - A high true level from the printer to indicate
the printer is in a fault condition.
SELECT - A high true level from the printer to indicate the printer is
ready for data transfer and the ONLINE key has been activated.
BUSY - A high true level from the printer to indicate the printer
cannot receive data.
ACKNOWLEDGE - A low true pulse from the printer indicating the
character or function code has been received and the printer is
ready for the next data transfer.
DATA STROBE - A low true, 100 ns minimum pulse from the host
to clock data into the printer.
DATA LINES - Eight standard or inverted levels from the host that
define the data, which may consist of a character or function code.
Sensing Data Line 8 is controlled by printer configuration.
PAPER INST - Optional VFU control signal from the host with the
same timing and polarity as the data lines. Sensing of the PAPER
INST line (PI line) is controlled by printer configuration.
PRIME - Optional low true signal from the host used to reset the
printer to its default power-up state.
NFAULT - A low true level from the printer to indicate the printer is
in a fault condition.
NOTE: The PAPER INST line must be disabled (configuration
option selected from the control panel) if the host computer
does not drive or control it. If the line is not controlled by the
host and PAPER INST line sensing is enabled in the
printer, rapid paper slewing will occur.
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