SWCU192 November 2021 CC1312R7 , CC1352P7 , CC2652P7 , CC2652R7
The transmit operations contain a buffer with the data to be transmitted. The number of bytes in this buffer is given by pktLen. For the CMD_PROP_TX command, the length given in pktLen is transmitted as the first byte if pktConf.bVarLen is 1, and then followed by the contents of the transmit buffer.
For CMD_PROP_TX_ADV, the first bytes of the buffer contain the header if the header length is greater than 0. The number of bytes is the number of bits in the header divided by 8, rounded up. The MSBs of the last header byte are not sent if the number of bits does not divide by 8. If a length field is to be transmitted using CMD_PROP_TX_ADV, it must be given explicitly from the system side as part of the header.
If unlimited length is configured, a TX queue is used instead of one buffer. In this case, transmission of payload continues until the queue is emptied. Every time transmission from one entry is finished, meaning reading continues from the next entry or the entire payload is entered into the modem, a TX_ENTRY_DONE interrupt is raised.