5.3.4.9 Set PHY Preference

Format: CSPHY,<hex16>,<hex8>,<hex8>,<hex8>

Use this command to set the PHY preferences for the specified connection. The CSPHY command expects four input parameters. The first parameter is a 16-bit hex value that indicates which connection handle corresponds to a specific Bluetooth Low Energy connection. The second parameter is an 8-bit bitmap defined in Table 5-46 that sets the preferred PHY’s transmitter. The third parameter is an 8-bit bitmap to set the preferred PHY's receiver. For the value definition, refer to Table 5-46. The last is the PHY option, which is used when the coded PHY is selected and defined in Table 5-47.

Table 5-46. Bitmap of PHY’s
PHY’s Bitmap (HEX)	Description
00	No preferred
01	1M PHY
02	2M PHY
04	Coded PHY

Table 5-47. Bitmap of PHY’s Option
PHY’s Option (HEX)	Description
00	No preferred
01	S2 coded PHY
02	S8 coded PHY


Item	Firmware Version 1.0 and Later	Description
Example:	`CSPHY,0071,03,03,00`	Set the preferred PHY of TX and RX to 1M/2M PHY in the Bluetooth® Low Energy link for connection handle 0x0071
Response:	`AOK`	Success
	`Err`	Syntax error or invalid parameter
	`%PHY_UPDATED,<ConnHandle>,<Tx PHY>,<Rx PHY>%`	PHY update success status report
	`%ERR_PHYUPDATE,<ConnHandle>%`	PHY update fail status report
Note: Use this command only when the Bluetooth Low Energy connection(s) exists. For more details on the TX PHY and RX PHY values of the PHY update status report, see Table 5-48. The PHY preference set over the connection must not be maintained. The command is associated with the connection handle, which is unique for every command. Hence, the PHY preference needs to be set for every new connection.