PC Parallel Interface SignalsData Lines 1 through 8. Provides eight standard or inverted levels from the hostthat specify character data, plot data, or a control code. Data Line 8 allows accessto the extended ASCII character set. You may enable or disable this line via theData Bit 8 parameter on the Centronics submenu.Data Strobe. Carries a low true, 100 ns minimum pulse from the host that clocksdata into the printer.Paper Instruction (PI). Carries a CVFU signal from the host with the same timingand polarity as the data line.Acknowledge. A low true pulse from the printer indicating the character orfunction code has been received and the printer is ready for the next data transfer.Online/Select. A high true level from the printer to indicate the printer is ready fordata transfer and the Start key on the operator panel has been activated. When theprinter is in Ready mode, it may accept data from the host.Paper Empty (PE). A high true level from the printer to indicate the printer is in apaper empty or paper jam fault.Busy. A high true level from the printer to indicate the printer cannot receive data.PC Parallel Interface ConfigurationYour printer is configured at the factory to match the interface you specified. Byusing the operator panel, you may verify and change several interface parametersto meet specific application requirements.Refer to “PC Parallel Menu” on page 129 for PC Parallel parameter descriptionsand information on selecting values for the following parameters:v Data Bit 8 (enable or disable)v Data Polarity (standard or inverted)v Strobe Polarity (standard or inverted)v Response Polarity (standard or inverted)v Busy on Strobe (enable or disable)v Latch Data On Leading or Trailing Edge of Strobev Prime Signal (enable or disable)v TOF Action at Prime Signal (do nothing or form feed)v Buffer Size in kilobytes (1 to 16)Some application programs require a unique configuration. If the printer is notworking properly in the configuration you have selected, contact an IBM servicerepresentative.Chapter 5. Printer Interfaces 211
