Specifications

CHAPTER 1
Introduction to the LaserWriter 16/600 PS Printer
Communication Ports 7
Table 1-2 lists the pin functions for the 9-pin mini-DIN connector for LocalTalk.
Note
In the LaserWriter 16/600 PS printer, the /TXD signal is connected to
the /RXD signal, and the TXD signal is connected to the RXD signal.
◆
Centronics Parallel Connector (IEEE 1284) 1
The LaserWriter 16/600 PS printer provides a 36-pin connector for bidirectional
communication with a Centronics (IEEE1284) parallel interface. The connector is fully
compatible with the IBM PC Centronics port, and from a software perspective, the port
operates exactly as a Hewlett-Packard LaserJet 4 Bi-Tronics parallel interface. The
Centronics interface also supports the high-speed parallel interface. The high-speed
capability of the parallel port can be enabled or disabled with the Macintosh Apple
Printer Utility or the Windows LaserWriter Utility, as well as with PostScript operators.
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 PAPER ERR and /FAULT, which flag paper errors. It also returns handshaking
signals such as BUSY and /ACK.
Figure 1-4 shows the pin designations for the parallel connector, and Table 1-3 lists the
signal descriptions. Signal names in parenthesis are specific to the IEEE 1284 interface.
Figure 1-5 shows the timing requirements for the Centronics interface.
Figure 1-4 The Centronics (IEEE 1284) parallel connector
Table 1-2 Signal descriptions for LocalTalk connector
Pin
number Signal name Description
1, 2, 7 NC Not connected
3 /TXD Transmit data (inverted)
4 GND Signal ground
5 /RXD Receive data (inverted)
6 TXD Transmit data
8 RXD Receive data
9 +5 +5 volts power
Pin 18
Pin 36
Pin 1
Pin 19