User`s manual

34 Functional Description
3.3 Board Interfaces
USB Interfaces
The cPCI-3920 supports six USB 2.0 ports:
X one front I/O
X two front I/O on DB-3920L2 module
X one onboard to connect a Flash disk
X two on the Rear I/O module.
On the USB 2.0 front panel port, USB cable with up to 5 meters in
length can be used.
On the USB 2.0 Rear I/O ports, it is strongly recommended to use
a cable below 3 meters in length for USB 2.0 devices.
The USB 2.0 ports are high-speed, full-speed, and low-speed
capable. Hi-speed USB 2.0 allows data transfers of up to 480 Mb/s
- 40 times faster than a full-speed USB (USB 1.1). One USB
peripheral may be connected to each port.
To connect more USB devices than there are available ports, an
external hub is required.
Front Panel USB Connectors (CN2, CN4 -2, CN5-2)
Table 3-4: Front Panel USB Connector Pin Definition
Pin # Signal Name
1Vcc
2UV0-
3UV0+
4GND
NOTE:
NOTE:
The cPCI-3920 host interfaces can be used with maximum 500
mA continuous load current as specified in the Universal Serial
Bus Specification, Revision 2.0. Short-circuit protection is pro-
vided. All the signal lines are EMI-filtered.