Digi XBee DigiMesh 2.4, Руководство пользователя

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AT commands MAC/PHY commands
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide 76
Default
0
DB (Last Packet RSSI)
Reports the RSSI in -dBm of the last received RF data packet. DB returns a hexadecimal value for the -
dBm measurement.
For example, if DB returns 0x60, then the RSSI of the last packet received was -96 dBm.
DB only indicates the signal strength of the last hop. It does not provide an accurate quality
measurement for a multihop link.
If the XBee/XBee-PRO DigiMesh 2.4 has been reset and has not yet received a packet, DB reports 0 .
This value is volatile (the value does not persist in the device's memory after a power-up sequence).
Parameter range
N/A
Default
0
GD (Good Packets Received)
This count increments when a device receives a good frame with a valid MAC header on the RF
interface. Received MAC ACK packets do not increment this counter. Once the number reaches
0xFFFF, it does not count further events.
To reset the counter to any 16-bit unsigned value, append a hexadecimal parameter to the command.
This value is volatile (the value does not persist in the device's memory after a power-up sequence).
Parameter range
N/A
Default
N/A
EA (MAC ACK Failure Count)
The number of unicast transmissions that time out awaiting a MAC ACK. This can be up to RR +1
timeouts per unicast when RR > 0.
This count increments whenever a MAC ACK timeout occurs on a MAC-level unicast. When the number
reaches
0xFFFF , the firmware does not count further events.
To reset the counter to any 16-bit unsigned value, append a hexadecimal parameter to the command.
This value is volatile (the value does not persist in the device's memory after a power-up sequence).
Parameter range
N/A
Default
N/A