SWCU192 November 2021 CC1312R7 , CC1352P7 , CC2652P7 , CC2652R7
IEEE 802.15.4g PHY, including header, is supported by using the CMD_PROP_RX_ADV and CMD_PROP_TX_ADV commands.
The radio is configured to IEEE 802.15.4g mode by setting the formatConf.whitenMode field to the values 4, 5, 6, or 7, and formatConf.bMsbFirst must be set to 1 using the CMD_PROP_RADIO_DIV_SETUP command. For the CMD_PROP_TX_ADV and CMD_PROP_RX_ADV commands, pktConf.bCrcIncSw and pktConf.bCrcIncHdr must both be set to 0. For CMD_PROP_RX_ADV, hdrConf.numHdrBits must be set to 16, hdrConf.lenPos must be set to 0, hdrConf.numLenBits must be set to 11, and lenOffset must be −4.
When formatConf.whitenMode is 5 or 7, the radio is configured to produce the 32-bit CRC and whitening defined in IEEE 802.15.4g. When formatConf.whitenMode is 6 or 7, the radio also processes the headers in both receive and transmit as follows:
The IEEE 802.15.4g PHY header must be presented MSB first to the RF Core. In IEEE 802.15.4g specification, the payload part is LSb first, however the payload length info in physical layer header (PHR) is MSb first. This means that the payload needs to be flipped in the System CPU. This can be achieved with the System CPU assembly instruction RBIT.
The following example shows how to send a CRC-32 IEEE 802.15.4g frame with whitening enabled using the automatic headers processing feature (formatConf.whitenMode = 7).
/*
* Prepare the .15.4g PHY header
* MS=0, Length MSBits=0, DW and CRC settings read from 15.4g header (PHDR) by RF core.
* Total length = transmit_len (payload) + CRC length
*
* The Radio will flip the bits around, so tx_buf[0] must have the
* length LSBs (PHR[15:8] and tx_buf[1] will have PHR[7:0]
*/
/* Length in .15.4g PHY HDR includes the CRC but not the HDR itself */
uint16_t total_length;total_length = transmit_len + CRC_LEN; /* CRC_LEN is 2 for CRC-16 and 4 for CRC-32 */tx_buf[0] = total_length & 0xFF;
tx_buf[1] = (total_length >> 8) + 0x08 + 0x0; /* Whitening and CRC-32 bits */
tx_buf[2] = data;
An MCE patch is necessary to support FEC, Mode Switch, or other advanced features of IEEE 802.15.4g PHY.