Operation
Networking
The default value for the MM configuration parameter is 0 which enables both the Digi header and the
MAC acknowledgment.
XBee retries configuration
Configures the maximum number of retries the device executes in addition to the three retries
provided by the 802.15.4 MAC. RR (XBee Retries) controls XBee retries configuration. It is also known
as Application Retries.
For each XBee retry, the 802.15.4 MAC can execute up to three retries.
This only applies if MAC Mode configuration has Digi Header enabled.
Transmit status based on MAC mode and XBee retries configurations
When working in API mode, a transmit request frame sent by the user is always answered with a
transmit status frame sent by the device, if the frame ID is non-zero.
The following tables report the expected transmit status for unicast transmissions and the maximum
number of MAC and application retries the device attempts.
The tables also report the transmit status reported when the device detects energy above the CCA
threshold (when a CCA failure happens).
The following table applies in either of these cases:
l
Digi Header is disabled.
l
Digi Header is enabled and XBee Retries (RR parameter) is equal to 0 (default configuration).
Destination reachable
Retries
Destination unreachable
Retries
CCA failure happened
Retries
TX
Mac ACK
Config
MAC App TX status
MAC App status
MAC App
TX status
Enabled
00
(Success)
up to
3
0
0
01 (No
acknowledgment
received)
3
0
0
02 (CCA
failure)
3
0
Disabled 00
(Success)
0
00 (Success)
0
02 (CCA
failure)
3
0
The following table applies when:
l
Digi Header is enabled and XBee Retries (RR parameter) is bigger than 0.
XBee/XBee-PRO S2C 802.15.4 RF Module User Guide
43
ETC [ ETC ]
