Silicon Laboratories CP250 Series User Manual page 8

CP2501-DK
5.1. Switch and LEDs
The RESET switch is connected to the RST pin of the CP250x. Pressing RESET puts the device into its hardware-
reset state.
Four LEDs are also provided on the motherboard. The red LED labeled "PWR" (D4), indicates a power connection
to the motherboard. The green LED labeled "RUN" (D10) turns on when the debug circuitry is in a running state;
the red LED labeled "STOP" (D11) turns on when the debug circuitry is in a halted state, and the orange LED
labeled "DEBUG PWR" (D12) indicates whether the debug adapter circuit is being powered through P5's USB
connector. Table 2 lists the port pins and headers corresponding to the switch and LEDs.
Description
RESET
Red LED labeled "PWR"
Green LED labeled "RUN"
Red LED labeled "STOP"
Orange LED labeled "DEBUG PWR"
5.2. Power Supply Headers (P3, J3, and J7)
The main power supply of the motherboard, which is used to power the daughter board, can be provided by either
the USB debug device's on-chip voltage regulator or P3 and its associated circuitry. To select a power supply, place
a shorting block on J3 across the appropriate pin pair, as shown in Figure 5. To connect the main power supply to
an attached daughter board, place a shorting block across J7.
Notes:
1. Only two of the pins on the J3 header should be connected at any one time
To use the USB debug device's voltage regulator as the board's power supply, a USB cable must be
2.
connected to P5, and the DEBUG PWR LED (D12) must be on.
Figure 5. J3 and J7 Shorting Block Configuration for Power Options
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Table 2. Motherboard LED and Switch Descriptions
Component Name
SW3
D4
D10
D11
D12
VDD_PWR
J7
J3
VDD_DEBUG
VDD_CP250x
VDD_PWR
+3VD
+3.3V Regulator Power
(From P3)
Daughter Board's RST/C2CK
Daughter Board's VDD
Debug Adapter Signal
Debug Adapter Signal
Debug Adapter Signal
VDD_PWR
J7
J3
VDD_CP250x VDD_DEBUG
Debug Circuit Power
(From USB at P5)
Rev. 0.1
I/O Header
None
J3, J7
None
None
None
VDD_PWR
+3VD