
121
42073A-MCU Wireless-02/13
ATmega2564/1284/644RFR2
This register sets the threshold level for the Energy Detection (ED) of the Clear Channel
Assessment (CCA).
Bit 7:4 – CCA_CS_THRES3:0 - CS Threshold Level for CCA Measurement
These bits are reserved for internal use.
Bit 3:0 – CCA_ED_THRES3:0 - ED Threshold Level for CCA Measurement
These bits define the received power threshold of the Energy above threshold
algorithm. The threshold is calculated by RSSI_BASE_VAL + 2CCA_ED_THRES
[dBm]. Any received power above this level is interpreted as a busy channel.
9.12.15 RX_CTRL – Transceiver Receive Control Register
Bit
7
6
5
4
NA ($14A)
SDM_MODE1
SDM_MODE0
ACR_MODE
SOFT_MODE
RX_CTRL
Read/Write
RW
Initial Value
1
0
1
Bit
3
2
1
0
NA ($14A)
PDT_THRES3
PDT_THRES2
PDT_THRES1
PDT_THRES0
RX_CTRL
Read/Write
RW
Initial Value
0
1
The register controls the sensitivity of the Antenna Diversity Mode. Note that in High
Data Rate modes the ACR module will always be disabled.
Bit
7:6
–
SDM_MODE1:0
-
Sigma-Delta
Modulator
Order
and
Delay
Compensation
These bits are reserved for internal use. They select the order of the sigma-delta
modulator (SDM), turn on or off the delay compensation unit (DCU) and other internal
functions.
Table 9-48 SDM_MODE Register Bits
Register Bits
Value
Description
SDM_MODE1:0
0
SDM mode 1 selected (Mash 1), DCU turned
on
1
SDM mode 1 with random carry threshold
2
SDM mode 2 selected (Mash 1-1), DCU
turned on
3
SDM mode 2 with random ACCU2
Bit 5 – ACR_MODE - Adjacent Channel Rejection Mode
This bit is reserved for internal use. It turns on or off the ACR module. For high rate
modes the ACR module will be always disabled.
Bit 4 – SOFT_MODE - Correlator Soft Mode
This bit is reserved for internal use. It controls the correlation function of the digital
baseband processor. Furthermore the bit enables or disables the data scrambling in the
high data rate modes.
Bit 3:0 – PDT_THRES3:0 - Receiver Sensitivity Control