Lexmark Forms Printer 2481 Technical Reference - Page 94

Parallel Pin Assignments Pin Line Description 1 STROBE* When the printer receives the STROBE* low from the computer, the printer reads the data from the interface and sets the BUSY line high. STROBE* must not occur when the BUSY line is high; otherwise, unpredictable results may occur. 2-9 DATA These signals are the 8 bits of parallel data sent from the computer. A high level indicates a logical 1. A low level indicates a logical 0. The printer reads data from the DATA lines when a STROBE* pulse is received. 10 ACKNLG* The ACKNLG* pulse tells the computer that the data from the previous STROBE* pulse has been read. An ACKNLG* pulse is also generated when the printer is turned on, or at the completion of the printer initialization by an INIT* requested from the computer. 11 BUSY When the printer sets BUSY high, it cannot receive data. The BUSY line goes high in response to a STROBE* pulse. This line remains high until the data is read. BUSY is also high when: • The receive buffer is full. • An out-of-paper condition occurs. • The printer receives an INIT* signal. • Start/Stop is pressed to go offline. • A printer error condition has occurred. • The printer is initializing. 12 PE The printer sets Paper End (PE) high when approximately 12.7 mm (0.5 in.) of paper remains in the printer. PE remains high until the operator loads paper and presses Start/Stop. 13 SLCT When the printer is ready, it sets the SLCT line high. The SCLT lines go low when: • Start/Stop is pressed to go offline. • There is an error or out-of-paper condition. • The printer receives an ESC Q. It ignores all incoming data except DC1, which returns the printer to a select state. 14 AUTO The printer executes one line feed when this signal, valid only FEED XT in Epson** mode, is low. 15 Not used. 16 GND Logic ground. 17 CHASSIS Ground level. GROUND 18 +5 volts Maximum 300 mA. 19-30 GND Ground level. * Inverted logic (signal is active when low). 94 Section 6: Using the Printer Interface