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42073A-MCU Wireless-02/13
ATmega2564/1284/644RFR2
These register bits control the sensitivity of the receiver correlation unit. If the Antenna
Diversity algorithm is enabled the value shall be set to PDT_THRES = 3. Otherwise it
shall be set back to the reset value. Values not listed in the following table are reserved.
Table 9-49 PDT_THRES Register Bits
Register Bits
Value
Description
PDT_THRES3:0
0x7
Reset value, to be used if Antenna Diversity
algorithm is disabled
0x3
Recommended correlator threshold for
Antenna Diversity operation
9.12.16 SFD_VALUE – Start of Frame Delimiter Value Register
Bit
7
6
5
4
3
2
1
0
NA ($14B)
SFD_VALUE7:0
SFD_VALUE
Read/Write
RW
Initial Value
1
0
1
0
1
This register contains the one octet start-of-frame delimiter (SFD) to synchronize to a
received frame. The lower 4 bits must not be all zero to avoid decoding conflicts.
Bit 7:0 – SFD_VALUE7:0 - Start of Frame Delimiter Value
For compliant IEEE 802.15.4 networks set SFD_VALUE = 0xA7. This is the default
value of the register. To establish non IEEE 802.15.4 compliant networks the SFD value
can be changed to any other value. If enabled a RX_START interrupt is issued only if
the received SFD matches the register content of SFD_VALUE and a valid PHR is
received.
Table 9-50 SFD_VALUE Register Bits
Register Bits
Value
Description
SFD_VALUE7:0
0xA7
IEEE 802.15.4 compliant value of the SFD
9.12.17 TRX_CTRL_2 – Transceiver Control Register 2
Bit
7
6
5
4
NA ($14C)
RX_SAFE_MODE
Res4
Res3
Res2
TRX_CTRL_2
Read/Write
RW
R
Initial Value
0
Bit
3
2
1
0
NA ($14C)
Res1
Res0
OQPSK_DATA_RATE1 OQPSK_DATA_RATE0
TRX_CTRL_2
Read/Write
R
RW
Initial Value
0
This register controls the data rate setting of the radio transceiver.
Bit 7 – RX_SAFE_MODE - RX Safe Mode
If this bit is set, the next received frame will be protected and not overwritten by
following frames. Set this bit to 0 to release the buffer (and set it again for further
protection).
Bit 6:2 – Res4:0 - Reserved