Sony PCV-RS421 - Manual (Page 13)

Connection for a PS/2 ® mouse.
3 Keyboard port
Connection for a PS/2 ® keyboard.
4 Ethernet port
Connection for a 10BASE-T/100BASE-TX Ethernet interface.
(The port marked with (Network) is for LAN connections only.)
5 Universal Serial Bus (USB 2.0) ports (2)
Connections for compatible high/full/low-speed USB devices.
6 Monitor port
Connection for a display.
7 Printer port
Connection for a parallel device, such as a printer or scanner.
8 i.LINK 6-pin S400 port (IEEE 1394)
Connection for a compatible digital device.
9 Serial port
Connection for a compatible serial device.
10 Headphones jack
Connection for the supplied speakers or optional headphones.
Line In jack
Connection for an audio device.
Microphone jack
Connection for a microphone (optional).
11 Telephone jack
Connection for a telephone cable (optional) to the computer.
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