Chapter 2 External I/O Specification External I/O Specification This section describes the external I/O for the printer. Distinguishing Between New and Old Circuit Boards There are two external I/O circuit boards that differ in their signal voltage range and current electrical specifications. Check the difference between the new and old circuit boards according to the presence of an “H” mark on the frame of the external I/O connector on the backside of the printer. New circuit board Old circuit board 2 EXT.I/F H EXT.I/F Connector The external I/O connectors are as follows. D-sub25 connector (female connector) Screws:
Metric screws 13 1 25 14 Signal Definitions from High to Low, maintains a low state for a short period of time, and then sharply changes back to High. A High active pulse is a signal that changes sharply from Low to High, maintains a High state for a short period of time, and then sharply changes back to Low. If a pulse signal meets the specification for pulse width, the time for the pulse width does not matter. 11 Q NOTE Be sure to use the screws to affix the connection cable and ensure the cable does not fall out. Pulse signal A pulse signal is a square wave with a fixed short-term width. A low active pulse is a signal that changes sharply