C8051F70X_0910 Datasheet, PDF (287/290 Pages) Silicon Laboratories – Mixed Signal ISP Flash MCU Family

C8051F70x/71x
33.2. C2CK Pin Sharing
The C2CK pin is shared with the RST signal on this device family. If the RST pin is used by other parts of
the system, debugging and programming the device can still be accomplished without disrupting the rest of
the system. If this is desired, it is normally necessary to add a resistor to isolate the system’s reset line
from the C2CK signal. This external resistors would not be necessary for production boards, where debug-
ging capabilities are not needed. A typical isolation configuration is shown in Figure 33.1.
RST
C2CK
C2D
C2 Interface Master
Figure 33.1. Typical C2CK Pin Sharing
The configuration in Figure 33.1 assumes the RST pin on the target device is used as an input only. Addi-
tional resistors may be necessary depending on the specific application.
Rev. 0.3
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