zic2410 California Eastern Laboratories, zic2410 Datasheet - Page 78

• Manufacturer Part Number: zic2410
• Description: Single-chip Solution, Compliant With Zigbee
• Manufacturer: California Eastern Laboratories

CCA1 (CCA CONTROL CONFIGURATION1 REGISTER, 0x2249) R/W. CCA Decision
Threshold.
This register defines threshold of energy level to determine whether a channel state is busy.
This register is used only when CCA methods based on energy detection are used. The
CCATHRS threshold is stored as a 2’s complement integer in dBm. The default value of
CCATHRS register is 0xB2 and corresponds to ‘-78dBm’.
CCA2 (CCA CONTROL CONFIGURATION2 REGISTER) R/W. Energy Calculation
Offset(ENRGOFST)
The ZIC2410 and calculates the energy level of the received signal based on the gain of RF
block per the following equation.
As Equation 4 above describes, the CCA2 register compensates for an offset of calculated
energy level for the received signal. A user can set the difference between the energy level
calculated on a developed system and the real energy level of the received signal in the CCA2
register.
Bit
6:4
1:0
3
2
Rev A
CCAFIX
CCAMD
Name
CCAA
WS
When CCA uses the energy detection method, it sets the average
duration for the received signal energy.
CCA Indication Lock-up. Fixes the communication channel state to
idle. A com channel state is determined by the CCA circuit in the
ZIC2410. When a channel state is busy, a packet is not transmitted.
This field allows packet transmission regardless of the channel state.
When this field is set to ‘1’, the channel is always in idle state.
Reserved
CCA Indication Mode: Sets the method to determine the com channel
state. The following describes the three methods to detect the channel
state.
ED (Energy Detection): This method determines the channel state as
‘busy’ when the energy of a received signal is higher than the defined
level.
CD (Carrier Detection): This method determines the channel state as
‘busy’ when an IEEE802.15.4 carrier is detected.
FD (Frame Detection): This method determines the channel state as
‘busy’ when the normal IEEE802.15.4 packet is detected.
CCAAWS
Equation 4 – Calculation of RX Signal Energy Level
others
CCAMD
0
1
2
3
Energy Level (dBm) = CCA2 – RF_GAIN
0
1
2
3
Document No. 0005-05-07-00-000
ZIC2410 Datasheet
Descriptions
Average Calculation Duration
Reserved
16µs
Method
1µs
2µs
4µs
8µs
ED
CD
FD
Page 78 of 119
R/W
R/W
R/W
R/W
Reset
Value
100
00
0
1