User's Manual

If SEP_DI_DO = 0 in the INTERFACE register, the DIO pin is the data output in receive mode and data
input in transmit mode. The DCLK pin is not active and can be set to a high or low level by
DATA_FORMAT[0].
If SEP_DI_DO = 1 in the INTERFACE register, the DCLK pin is the data output in receive mode and the
DIO pin is the data input in transmit mode. In TX mode the DCLK pin is not active and can be set to a high
or low level by DATA_FORMAT[0]. See Figure 10.
Manchester encoding and decoding
In the synchronous Manchester encoded mode CC1020 uses Manchester coding when modulating the data.
The CC1020 also performs the data decoding and synchronization. The Manchester code is based on
transitions; a “0” is encoded as a low-to-high transition, a “1” is encoded as a high-to-low transition. See
Figure 11.
The Manchester code ensures that the signal has a constant DC component, which is necessary in some
FSK demodulator.
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