RF Testing using BTool¶

Note

For a step by step explanation about how to execute a sequence of commands for testing, please refer to the Application Note on How to Do RF Radio Test With Your Bluetooth Product. Please consider that this guide has been specially developed for CC26xx devices but is still applicable for CC23xx devices considering differences in commands (such for CC23xx & CC27xx devices considering differences in commands (such as the ones used for setting TX Power). Information related to Packet Error Rate (PER) and RSSI measurements can be found there.

Tool Configuration¶

In order to set the device to perform RF tests, we need an image capable of receive and executing HCI commands.
- Flash the device with the respective host_test example, which can be found inside the SDK folder <SDK>/examples/rtos/LP_EM_CC23xx/ble/host_test. It is also possible to use projects that have Production Test Mode <SDK>/examples/rtos/DEVICE/ble/host_test. Specifically for CC23xx, It is also possible to use projects that have Production Test Mode (PTM) enabled functionalities such as the example found in <SDK>/examples/rtos/LP_EM_CC2340R5/ble/basic_ble_ptm. You can import the project in CCS or IAR and tune it to fit your own design (e.g. change the UART mapping).
- If your design allows it (or if you are running the tests on a TI LaunchPad), you can directly flash the pre-built hexfile on the device. To do so, use UniFlash and use the following image <SDK>/examples/rtos/DEVICE/ble/prebuilt_hexfiles/host_test_app.hex. <SDK>/examples/rtos/DEVICE/ble/prebuilt_hexfiles/host_test_app.hex.
- Finally, it is recommended to power cycle the device after flashing it.
BTool can be found within the SDK. Execute the file <SDK>/tools/ble/btool/btool.exe to open the tool.
When opening BTool, you are prompted to select the COM interface used by your device. Make sure to choose the interface COMXX - XDS110 Class Application/User UART.

Figure 55. Btool Prompt.¶

At start BTool automatically sends a few commands to the device. These commands are not relevant for this use case, so just wait for the commands to be executed, then right click on the log and click Clear Log.
Move to the panel Advanced Commands. From this panel you can send commands to the device. For this use case, the commands within HCI Extended and HCI should be the most useful.
Send a reset command HCI_Reset. A UART command is sent to the device (displayed in green) and the device resets and sends back an answer.

Figure 56. BTool interface - Advanced Commands¶

Assuming you have reached this point, it means the device is properly flashed, the UART commands are properly sent and executed by the device. Now we can look at sending more test commands to the device.

The HCI commands are specified by the Bluetooth Specifications. In order to offer more testing possibilities, these commands are completed by HCI Extended commands. Documentation for all these commands can be found in the commands for both CC23xx and CC27xx can be found in the API references section of the user’s guide.

Only a subset of the commands will be used for testing (see below). Commands in bold are the ones commonly used:

Continuous Wave (Non-signaling)

Command

Parameters

Comments

HCI_Reset

none

To reset the device

HCIExt_EndModemTestCmd

none

To terminate a modem test

HCIExt_ModemTestTxCmd

Modulation, Channel

For the 1M PHY only

HCIExt_ModemTestRxCmd

Channel

For the 1M PHY only

HCIExt_EnhancedModemTestTxCmd

Modulation, PHY, Channel

HCIExt_EnhancedModemTestRxCmd

PHY, Channel

HCI_ReadRssi

none

To read RSSI

HCIExt_SetTxPowerDbmCmd

dBm, fraction (not used)

To set TxPower for modem tests

Direct Test Mode - DTM (Signaling)

Command

Parameters

Comments

HCI_Reset

none

To reset the device

HCI_LE_TestEnd

none

To terminate a DTM test

HCI_LE_TransmitterTest

Channel, Data Length, Data

For the 1M PHY only

HCI_LE_ReceiverTest

Channel

For the 1M PHY only

HCI_LE_EnhancedTransmitterTest

Channel, Data Length, Payload, PHY

Payload to be selected from DTM standard

HCI_LE_EnhancedReceiverTest

Channel, PHY, modulationIndex

HCI_ReadRssi

none

To read RSSI

HCIExt_SetMaxDtmTxPowerDbmCmd

dBm, fraction (not used)

To set TxPower for DTM tests

Hands-on Examples¶

Let’s try some of them! You will be able to see the log that is produced in BTool. Highlighted in yellow are the commands to send and the parameters you should make sure to set. Highlighted in blue are the events received from the device (a non-SUCCESS answer means there has been an issue). Always remember to end the previous test before starting a new one.

Example 1: Set the device to transmit at 8dBm a Continuous Wave with 2M PHY on channel 1.

Figure 57. Display of command execution using Btool.¶

Example 2: Set the device to transmit at 8dBm a Continuous Wave with 2M PHY on channel 4. 1M PHY on channel 4.

Figure 58. Display of command execution using Btool.¶

Example 3: Set the device to transmit DTM packets at 5 dBm with 1M PHY on channel 36 with 37-byte payload of PRBS9.

Figure 59. Display of command execution using Btool.¶

Example 4: Set the device to transmit DTM packets at 5 dBm with 1M PHY on channel 36 with 37-byte payload of 0b11110000.

Figure 60. Display of command execution using Btool.¶

Example 5: Set the device to receive a Continuous Wave before ending it.

Figure 61. Display of command execution using Btool.¶

Warning

Command parameters (such as channel number, payload, TX power, etc) cannot be changed while a test is running. To perform such changes, you need to stop the current test by issuing the proper end commands.

Direct Test Mode (DTM) & Continuous Wave (CW) testing with basic_ble example¶

Now, let’s try to do both DTM and CW testing using the basic_ble example. First, make sure that the device is in peripheral mode from the SysConfig.

Figure 62. Sysconfig Page of Basic BLE Example.¶

Direct Test Mode¶

From app_peripheral.c :: Peripheral_start(), comment out the code which initializes and starts the advertising.

//Do not start advertising when entering DTM
  // status = BLEAppUtil_initAdvSet(&peripheralAdvHandle_1, &advSetInitParamsSet_1);
  // if(status != SUCCESS)
  // {
  //     // Return status value
  //     return(status);
  // }


  //    status = BLEAppUtil_advStart(peripheralAdvHandle_1, &advSetStartParamsSet_1);
  //    if(status != SUCCESS)
  //    {
  //        // Return status value
  //        return(status);
  //    }

Add the HCI DTM commands to start DTM. For this example, random values were used.

//DTM
  //Set the number of packets
  uint16_t txPktCnt = 1400;
  HCI_EXT_SetDtmTxPktCntCmd(txPktCnt);

  //Define the starting TX power
  int8 txPowerDbm = -8;
  uint8 fraction = 0;
  HCI_EXT_SetMaxDtmTxPowerDbmCmd(txPowerDbm, fraction);
  HCI_EXT_SetTxPowerDbmCmd(txPowerDbm, fraction);

  //Start DTM
  uint8 txChan = 11;
  uint8 payloadLen = 15;
  uint8 payloadType = HCI_DIRECT_TEST_PAYLOAD_0x0F;
  uint8 txPhy = HCI_PHY_1_MBPS;
  HCI_LE_EnhancedTxTestCmd(txChan,payloadLen, payloadType, txPhy);

Add a simple delay then end the test.

//Easy example of delay then end DTM
//The delay is necessary to give the device enough time to execute the commands
int i = 0;
int j = 0;
while(i < 300000){
    i++;
    if(i == 299999){
        j++;
        i = 0;
    }
    if (j == 20) {
        HCI_LE_TestEndCmd();
        i=300000;
    }
}

Re-enable BLE advertising. Do not forget to initialize the advertisement set parameters.

//Initialize the BLE advertisement set again
  status = BLEAppUtil_initAdvSet(&peripheralAdvHandle_1, &advSetInitParamsSet_1);
  if(status != SUCCESS)
  {
      // Return status value
      return(status);
  }

  //Start the BLE advertisement
  status = BLEAppUtil_advStart(peripheralAdvHandle_1, &advSetStartParamsSet_1);
  if(status != SUCCESS)
  {
      // Return status value
      return(status);
  }

Continuous Wave Testing¶

If desired, add the CW testing code immediately after step 3 of the DTM test setup.

Comment out the code which initializes and starts the advertising.

//Do not start advertising when entering DTM
  // status = BLEAppUtil_initAdvSet(&peripheralAdvHandle_1, &advSetInitParamsSet_1);
  // if(status != SUCCESS)
  // {
  //     // Return status value
  //     return(status);
  // }


  //    status = BLEAppUtil_advStart(peripheralAdvHandle_1, &advSetStartParamsSet_1);
  //    if(status != SUCCESS)
  //    {
  //        // Return status value
  //        return(status);
  //    }

Add the HCI CW commands to start the CW test.

//CW
//Setup parameters for CW test
  int cwMode = 0;
  txChan = 15;

  //Easy example of short delay before starting the CW test
  //The delay is only needed if you have done the DTM test before
  //The delay gives the device enough time to execute the HCI_LE_TEST_CMD
  i = 0;
  j = 0;
  while(i < 50000){
      i++;
      if(i == 49999){
          j++;
          i = 0;
      }
      if (j == 20) {
          HCI_EXT_ModemTestTxCmd(cwMode, txChan);
          i=5000000;
      }
  }

Add delay before ending the CW test. The command executed to end the test is different from DTM.

//Easy example of short delay before ending the CW test
//The delay is necessary to give the device enough time to execute the test
  i = 0;
  j = 0;
  while(i < 5000000){
      i++;
      if(i == 4999999){
          j++;
          i = 0;
      }
      if (j == 20) {
          HCI_EXT_EndModemTestCmd();
          i=5000000;
      }
  }

Re-enable BLE advertising.

//Correct the desired power level for the advertisement events
  txPowerDbm = 0;
  fraction = 0;
  HCI_EXT_SetMaxDtmTxPowerDbmCmd(txPowerDbm, fraction);
  HCI_EXT_SetTxPowerDbmCmd(txPowerDbm, fraction);

  //Initialize the BLE advertisement set again
  status = BLEAppUtil_initAdvSet(&peripheralAdvHandle_1, &advSetInitParamsSet_1);
  if(status != SUCCESS)
  {
      // Return status value
      return(status);
  }

  //Start the BLE advertisement
  status = BLEAppUtil_advStart(peripheralAdvHandle_1, &advSetStartParamsSet_1);
  if(status != SUCCESS)
  {
      // Return status value
      return(status);
  }