AT commands
MAC/PHY commands
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
74
CA (CCA Threshold)
Set or read the Clear Channel Assessment (CCA) threshold. Prior to transmitting a packet, the device
performs a CCA to detect energy on the channel. If the device detects energy above the CCA
threshold, it will not transmit the packet.
The
CA
parameter is measured in units of -dBm.
Setting the parameter to 0x00 disables CCA, otherwise the valid range is 0x24 - 0x50.
Parameter range
0x0 - 0x50 -dBm
Default
0x0 (CCA disabled)
Example
If you set the
CA
parameter to 60 (0x3C), the device does not transmit if it detects a signal greater
than -60 dBm on the channel.
ETSI compliance (Europe)
Use the following settings for ETSI compliance.
Device
Hex value Sets to level
XBee
0x3A
-58 dBm
XBee-PRO 0x43
-67 dBm
PL (TX Power Level)
Sets or displays the power level at which the device transmits conducted power.
For XBee,
PL
= 4,
PM
= 1 is tested at the time of manufacturing. Other power levels are approximate.
On channel 26, transmitter power will not exceed -4 dBm.
Parameter range
0 - 4
These parameters equate to the following settings for the XBee RF module:
Setting
Power level
0
-7 dBm
1
-1.7 dBm
2
-0.77 dBm
3
+0.62 dBm
4
+1.42 dBm
These parameters equate to the following settings for the XBee-PRO RF module:
