When the BTool and CC26xx/CC13xx devices are ready for test, start the RF Transmission Power test. [7] introduces this basic RF test. Equipment is needed to measure the power transmitted by the custom PCB, so you can use a Spectrum Analyzer or others dedicated for Bluetooth test, like Litepoint IQxel [8], Anitsu MT8852B [9] or R&S CMW270 [10].

The steps required for the Tx Test are the following:

1. Set Tx Power by setting HCIExt_SetTxPowerCmd
   Figure 3-2 Set HCIExt_SetTxPowerCmd
2. Let the CC26xx/CC13xx device enter Tx mode by setting HCIExt_ModemTestTxCmd.
   Figure 3-3 Set HCIExt_ModemTestTxCmd

   Note the channels passed as a parameter to the HCIExt_ModemTestTxCmd do not follow the Bluetooth Low Energy allocation. Instead, in sequence from 0 (2402 MHz) to 39 (2480 MHz), the Bluetooth Low Energy allocation starts at 37 (2402 MHz), then 0 (2404 MHz) until 39 (2480 MHz).

   Table 3-1 lists the channel index between both.

   Table 3-1 List of Channel Index

   Frequency (MHz)	Value of the Parameter txRfChannel Passed to HCIExt_ModemTestTxCmd	Corresponding Bluetooth Low Energy Channel
   2402	0	37
   2404	1	0
   2406	2	1
   …	…	…
   2424	11	10
   2426	12	38
   2428	13	11
   …	…	…
   2476	37	35
   2478	38	36
   2480	39	39

3. To test on a different PHY, call a HCIExt_EnhancedModemTestTxCmd.
   Figure 3-4 Set HCIExt_EnhancedModemTestTxCmd

By following the above steps, you can successfully run a Transmission Power test.