Apple 310 manual Centronics Parallel Connector, 2An 8-pin serial port connector

C H A P T E R 1

LaserWriter Select 310 Hardware

Figure 1-2An 8-pin serial port connector

8 7 6

5 4 3

2 1

Connected to chassis ground

Table 1-2	Signal descriptions for an 8-pin serial port
Pin	Signal
number	name	I/O	Description
1	DTR	I	Data terminal ready. Send data when this signal
			is asserted.
2	DSR	O	Data set ready.
3	/TXD	O	Transmit data (inverted)
5	/RXD	O	Receive data (inverted)
4, 6	GND	–	Ground
7, 8	Not used	–	These pins are not connected

Centronics Parallel Connector 1

The LaserWriter Select 310 printer provides a 36-pin connector for communication with a standard Centronics parallel interface. It is fully compatible with the IBM PC Centronics port.

The parallel channel is basically unidirectional and is used to input information from the host computer to the printer. The printer returns minimal status information to the host, such as /POUT and /FAULT, which flag paper errors. It also returns handshaking signals such as PBUSY and /PACK. If you require additional status information from the printer while you are printing to the parallel port, you can use a host computer running a terminal emulation at 9600 bauds to connect to the serial port of the printer.

Communication Ports 5