Texas Instruments CC2650DK ユーザーズマニュアル
IEEE 802.15.4
For operation according to IEEE 802.15.4, the parameters must be initialized as follows before starting a
new CSMA-CA operation:
new CSMA-CA operation:
•
randomState must be set to a random value
•
csmaConfig.initCW must be set to 2 for slotted CSMA-CA and 1 for unslotted CSMA-CA
•
csmaConfig.bSlotted must be set to 1 for slotted CSMA-CA and 0 for unslotted CSMA-CA
•
NB must be set to 0
•
BE must be set to macMinBE, except for slotted CSMA-CA with battery-life extension, where BE must
be set to min(2, macMinBE)
be set to min(2, macMinBE)
•
remainingPeriods must be set to 0
•
macMaxBE and macMaxCSMABackoffs must be set to their corresponding MAC PIB attribute
For slotted CSMA-CS, startTrigger must be set up to occur on a backoff-slot boundary. For slotted CSMA-
CA, the endTrigger must be set up to occur at the latest time that the transaction can be completed within
the superframe, as specified in the IEEE 802.15.4 standard. If the CSMA-CA ends due to timeout, the
CSMA can be restarted without modifying the parameters (except possibly the end time) at the next
superframe.
CA, the endTrigger must be set up to occur at the latest time that the transaction can be completed within
the superframe, as specified in the IEEE 802.15.4 standard. If the CSMA-CA ends due to timeout, the
CSMA can be restarted without modifying the parameters (except possibly the end time) at the next
superframe.
A CSMA-CA operation ends due to one of the causes listed in
. The status field of the
command structure after the command has ended indicates the reason why the operation ended. In all
cases, an FG_COMMAND_DONE interrupt is raised. In each case, it is indicated if the result is True,
False, or Abort. This indicates whether to start the next command (if any) in pNextOp, or to return to an
idle state.
cases, an FG_COMMAND_DONE interrupt is raised. In each case, it is indicated if the result is True,
False, or Abort. This indicates whether to start the next command (if any) in pNextOp, or to return to an
idle state.
Table 23-80. End of CSMA-CA Operation
Condition
Status Code
Result
CSMA-CA operation finished with success
IEEE_DONE_OK
True
CSMA-CA operation finished with failure
IEEE_DONE_BUSY
False
End trigger occurred
IEEE_DONE_TIMEOUT
False
Received CMD_STOP or CMD_IEEE_STOP_FG
IEEE_DONE_STOPPED
False
Received CMD_ABORT or CMD_IEEE_ABORT_FG
IEEE_DONE_ABORT
Abort
Background operation ended
IEEE_DONE_BGEND
Abort
Observed illegal parameter
IEEE_ERROR_PAR
Abort
When the operation ends, the time of the last CCA check (that is, the time written into lastTimeStamp) is
defined as event #1, and may be used for timing subsequent chained operations.
defined as event #1, and may be used for timing subsequent chained operations.
23.5.4.4 Transmit Operation
The transmit operation is a foreground-level operation that transmits one packet. The operation is started
with the CMD_IEEE_TX command, and uses the command structure given in
with the CMD_IEEE_TX command, and uses the command structure given in
When the radio CPU receives the command, it waits for the start trigger. Any background-level operation
keeps running during this wait time. At the start trigger, the radio CPU suspends the receiver and
configures the transmitter. It is assumed that the synth is powered and calibrated, so if no background-
level operation is running, the TX operation must be preceded with a calibrate synth command. If the
frequency synthesizer is not running, the operation ends with an error.
keeps running during this wait time. At the start trigger, the radio CPU suspends the receiver and
configures the transmitter. It is assumed that the synth is powered and calibrated, so if no background-
level operation is running, the TX operation must be preceded with a calibrate synth command. If the
frequency synthesizer is not running, the operation ends with an error.
The transmitter transmits the payload found in the buffer pointer to pPayload, which consists of
payloadLen bytes. If TXOpt.payloadLenMsb is nonzero, this field is multiplied by 256 and added to
payloadLen to create a long non-IEEE 802.15.4-compliant frame for test purposes. If
TXOpt.bIncludePhyHdr is 0, the radio CPU inserts a PHY header automatically, calculated from the
payload length. Otherwise, no PHY header is inserted by the radio CPU, so for IEEE 802.15.4
compliance, the first byte in the payload buffer must be the PHY header. The payload is then transmitted
as found in the payload buffer. If TXOpt.bIncludeCrc is 0, the radio CPU appends two CRC bytes,
calculated according to the IEEE 802.15.4 standard. Otherwise, no CRC is appended, so for IEEE
802.15.4 MAC compliance, the last two bytes in the payload buffer must be the MAC footer. The transmit
operation can be ended by one of the immediate commands CMD_ABORT, CMD_STOP,
payloadLen bytes. If TXOpt.payloadLenMsb is nonzero, this field is multiplied by 256 and added to
payloadLen to create a long non-IEEE 802.15.4-compliant frame for test purposes. If
TXOpt.bIncludePhyHdr is 0, the radio CPU inserts a PHY header automatically, calculated from the
payload length. Otherwise, no PHY header is inserted by the radio CPU, so for IEEE 802.15.4
compliance, the first byte in the payload buffer must be the PHY header. The payload is then transmitted
as found in the payload buffer. If TXOpt.bIncludeCrc is 0, the radio CPU appends two CRC bytes,
calculated according to the IEEE 802.15.4 standard. Otherwise, no CRC is appended, so for IEEE
802.15.4 MAC compliance, the last two bytes in the payload buffer must be the MAC footer. The transmit
operation can be ended by one of the immediate commands CMD_ABORT, CMD_STOP,
1511
SWCU117A – February 2015 – Revised March 2015
Radio
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