C8051F35x-DK
Rev. 0.1
9
6.10. External Voltage Reference(J13, J14)
A precision 2.5V Voltage reference source is also included on the C8051F350 target board. To use this circuit as a
reference source for the ADC, place shorting block on jumpers J13 and J14. Note that software on the device
should be configured to use an external reference when using this configuration. When using the internal (on-chip)
reference source, jumpers J13 and J14 should be left open.
7. Serial Adapter
The Serial Adapter provides the interface between the PC’s RS232 serial port and the C8051F35x’s in-system
debug/programming circuitry. The Serial Adapter connects to the C8051F350 C2 debug interface on the target
board using the 10-pin connector on the Serial Adapter labeled “JTAG”, see Figure 3. (The Serial Adapter supports
both Silicon Laboratories JTAG and C2 debug interfaces.). All Serial Adapters may be powered from the target
board, but the EC1 and EC2 Serial Adapter units cannot provide power to the target board. Table 5 shows the pin
definitions for the Serial Adapter’s JTAG connector.
Notes:
1. When powering the Serial Adapter via the JTAG connector, the input voltage to the JTAG connector’s
power pin must be 3.0 to 3.6 VDC. Otherwise, the Serial Adapter must be powered directly by connecting
the AC/DC adapter to the Serial Adapter’s DC power jack.
2. The Serial Adapter requires a target system clock of 32 Khz or greater.
Pin #
Description
1
3.0 to 3.6 VDC Input
2
GND (Ground)
4
TCK (C2DAT)
5
TMS
6
TDO
7
TDI (C2CLK)
3,8,9,10
Not Connected
Table 5. JTAG/DEBUG Connector Pin Descriptions
Pin 1
Serial
Adapter
Pin 2
JTA
G
Pw
r
Run/
Sto
p
RS232
Figure 3. Serial Adapter JTAG/DEBUG Connector
