Centronics Parallel Interface Signals
Centronics Parallel Interface Signals
Data Lines 1 through 8. Provides eight standard or inverted levels from the host that specify character data, plot data, or a control code. Data Line 8 allows access to the extended ASCII character set. You may enable or disable this line via the Data Bit 8 parameter on the Centronics submenu (see page 91).
Data Strobe. Carries a low true, 100 ns minimum pulse from the host that clocks data into the printer.
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.
Online. A high true level from the printer to indicate the printer is ready for data transfer and the ON LINE key on the control panel has been activated. When the printer is in online mode, it may accept data from the host.
Paper Empty (PE). A high true level from the printer to indicate the printer is in a paper empty or paper jam fault.
Busy. A high true level from the printer to indicate the printer cannot receive data.
Prime. A high true level from the host to indicate the printer should perform a warm start (printer is reset to the
Paper Instruction (PI). Carries a CVFU signal from the host with the same timing and polarity as the data line.
Fault. A low true level from the printer indicates a printer fault.
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