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CMD_IEEE_ABORT_FG, and CMD_IEEE_STOP_FG. If CMD_ABORT or CMD_IEEE_ABORT_FG is
received, the transmission shall end as soon as possible, in the middle of the packet. If CMD_STOP or
CMD_IEEE_STOP_BG is received while the radio CPU is waiting for the start trigger, the operation ends
without any transmission; otherwise, the transmission is finished, but the end status and result differ as
explained below.
When transmission of the packet starts, the trigger RAT time used for starting the modem is written to the
timeStamp field by the radio CPU. This time stamp is delayed by the firmware-defined parameter
startToTXRatOffset, compared to the configured start time of the CMD_IEEE_TX command. If the
transmitter and receiver have synchronized RAT timers, this timestamp will be the same as the timestamp
appended to the RX entry element, as in Section 23.6.3.1, Receive Buffers, although with estimation
uncertainty on the receiver side.
When the operation ends, the end time of the transmitted frame is defined as event #1, and may be used
for timing subsequent chained operations.
A transmit operation ends due to one of the causes listed in Table 23-81. 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.
Table 23-81. End of Transmit Operation
Condition Status Code Result
Packet transmitted IEEE_DONE_OK True
Received CMD_STOP or CMD_IEEE_STOP_FG, then finished
IEEE_DONE_STOPPED False
transmitting if started
Received CMD_ABORT or CMD_IEEE_ABORT_FG IEEE_DONE_ABORT Abort
Observed illegal parameter IEEE_ERROR_PAR Abort
23.5.4.5 Receive Acknowledgment Operation
The receive-ACK operation is a foreground-level operation that runs on top of a receive operation. The
operation starts with the CMD_IEEE_RX_ACK command, and uses the command structure given in
Table 23-60.
At the start of a receive-ACK operation, the radio CPU waits for the start trigger. If the receiver was
suspended due to a TX operation prior to the receive-ACK operation, the background-level RX operation
is not resumed until the start trigger occurs.
While the receive-ACK operation is running, the background-level RX operation runs normally. However,
in addition to looking for the packets, the operation looks for ACK packets with the sequence number
given in seqNo. The packet is stored in the receive queue only if configured to in the background-level
receive operation (frameTypes.bAcceptFt2Ack = 1). If ACK packets are filtered out in the background RX
operation, for an ACK packet the sequence number will be received, and if it matches, also the FCS.
If the ACK packet with the requested sequence number is received, the FCS is checked. If the CRC is
OK, the receive-ACK operation ends, otherwise it continues. If the ACK is received OK, the pending-data
bit of the header is checked.
In addition to the receive-ACK operation ending after receiving the ACK as described above, the operation
can end as a result of the end trigger given by endTrigger and endTime, or by a command. The
commands that can end the receive-ACK operation are the immediate commands CMD_ABORT,
CMD_STOP, CMD_IEEE_ABORT_FG, and CMD_IEEE_STOP_FG.
A receive-ACK operation ends due to one of the causes listed in Table 23-82. 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.
1512
Radio SWCU117A–February 2015–Revised March 2015
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