Silicon Laboratories C8051F340 User Manual page 8

C8051F34x
4.3. Universal Serial Bus (USB) Interface (J14)
A Universal Serial Bus (USB) connector (P3) is provided to facilitate connections to the USB interface on the
C8051F340. Table 2 shows the J14 pin definitions.
4.4. PORT I/O Connectors (J2 - J6)
In addition to all port I/O signals being routed to the 96-pin expansion connector, each of the five parallel ports of
the C8051F340 has its own 10-pin header connector. Each connector provides a pin for the corresponding port
pins 0–7, +3.3 VDC and digital ground. Table 3 defines the pins for the port connectors. The same pin-out order is
used for all of the port connectors.
4.5. USB Self-Powered Configuration (J8)
The C8051F340 target board can be configured as a self-powered USB device to take power from the USB cable
instead of the ac/dc adapter connected at P1. To configure the target boards as a self-powered USB device, short
the VREGIN and VBUS pins on the J8 header
Note: When the C8051F340 target board is self-powered from the USB, the Serial Adapter is not powered from the
target board. The Serial Adapter must be powered directly by connecting the ac/dc adapter to the Serial Adapters'
dc power jack. Also, the RS232 Serial Interface (P4) cannot be used when powering the target board from the
USB.
8
Table 2. USB Connector Pin Descriptions
Pin #
1
2
3
4
Table 3. J12–J19 Port Connector Pin Descriptions
Pin #
1
2
3
4
5
6
7
8
9 +3 VD (+3.3 VDC)
10
Description
VBUS
D-
D+
GND (Ground)
Description
Pn.0
Pn.1
Pn.2
Pn.3
Pn.4
Pn.5
Pn.6
Pn.7
GND (Ground)
Rev. 0.3