Dataproducts Parallel Interface
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Dataproducts Parallel Interface Signals
The Dataproducts interface signals are defined below.
READY - A high true signal from the printer indicating AC po wer
and DC voltages are present, paper is loaded properly, and the
printer is not in a fault condition.
ON LINE - A high true signal from the printer indicating the Re ady
Line is true and the ONLINE key on the control panel has been
activated. The printer is ready to accept data from the host.
DATA REQUEST - A high true signal from the printer to
synchronize host data transmission with printer timing. This s ignal
goes true when the printer is ready to receive data. It changes to
the false state shortly after the leading edge of the data strob e
signal.
DATA STROBE - A high true pulse from the host to indicate that
data is ready. The data strobe must remain high at least unt il the
Data Request line goes false.
DATA LINES - Eight standard or inverted levels from the host tha t
specify character data, plot data, or a control code. Sensin g Data
Line 8 is controlled by printer configuration.
PAPER INST - Optional standard or inverted level VFU contro l
signal from the host with the same timing and polarity as the data
lines. Sensing of the PAPER INST line (PI line) is controll ed by
printer configuration.
NOTE: The PAPER INST line must be disabled (configuration
option selected from the control panel) if the host compu ter
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.
Interface Verification - Two pins on the interface connector
jumpered together allow you to verify proper installation of the
interface connector.