Sony PCV-R558DS - Manual (Page 71)

System Board 57
USB Connectors
There are two USB ports at the rear panel, and one UBS port at the front
panel. Each permits connection of USB peripheral devices directly to the
system without having to use an external hub.
USB2 and USB2 are standard USB connectors accessible from the rear
panel. USB2 Header is a 4-pin single-line header that connects to a
standard USB connector (USB1) accessible at the bottom of the front
panel. An internal cable connects USB2 Header to an interface board
behind the front panel.
If more USB devices are needed, connect an external hub to any USB
connector.
USB2 Header (connects to USB1 on front panel)
Pin
Signal Name
1 USBVCC2
2 USBP1#
3 USBP1
4 Ground
USB1, USB2 connectors
Pin
Signal Name
1 USBVCC1 *
2 USBP0#
3 USBP0
4 Ground
KY0033.VSD
USB1 USB2
USB2 header