Continuous waveform transmission with the STM32WL55JC sub-GHz radio?

[KImlay]

Hi,

I am developing on the Nucleo-wl55jc2 development board and I am trying to program the sub-GHz radio to transmit a continuous wave (not sending data packets, just a waveform). I have attached my code below along with a zip of the project. This code has been simplified from the 'SUBGHZ_Tx_Mode' example program that can be generated using the example selector when generating a new project.

I have tested my code with a spectrum analyzer and an oscilloscope, and have not been able to pick up a signal on either.

Any help is appreciated.

- Kevin

    #define RADIO_MODE_STANDBY_RC        0x02
    #define RADIO_MODE_BITFIELD          0x70
     
    uint8_t RadioCmdSetFreq[4] = {0x1D, 0xCD, 0x65, 0x00};	// 500,000,000
    uint8_t RadioResult = 0x00;
    uint8_t RadioParam  = 0x00;
    uint8_t RadioMode   = 0x00;
    uint8_t RadioStatus = 0x00;
     
    int main(void)
    {
        HAL_Init();
        MX_SUBGHZ_Init();
     
        /* Set Sleep Mode */
    	if (HAL_SUBGHZ_ExecSetCmd(&hsubghz, RADIO_SET_SLEEP, &RadioParam, 1) != HAL_OK)
    	{
    		Error_Handler();
    	}
     
    	/* Set Standby Mode */
    	if (HAL_SUBGHZ_ExecSetCmd(&hsubghz, RADIO_SET_STANDBY, &RadioParam, 1) != HAL_OK)
    	{
    		Error_Handler();
    	}
     
    	/* Retrieve Status from SUBGHZ Radio */
    	if (HAL_SUBGHZ_ExecGetCmd(&hsubghz, RADIO_GET_STATUS, &RadioResult, 1) != HAL_OK)
    	{
    		Error_Handler();
    	}
    	else
    	{
    		/* Format Mode and Status receive from SUBGHZ Radio */
    		RadioMode   = ((RadioResult & RADIO_MODE_BITFIELD) >> 4);
     
    		/* Check if SUBGHZ Radio is in RADIO_MODE_STANDBY_RC mode */
    		if(RadioMode != RADIO_MODE_STANDBY_RC)
    		{
    			Error_Handler();
    		}
    	}
     
    	/* Set transmit frequency */
    	if (HAL_SUBGHZ_ExecSetCmd(&hsubghz, RADIO_SET_RFFREQUENCY, RadioCmdSetFreq, 4) != HAL_OK)
    	{
    		Error_Handler();
    	}
     
    	/* Set Tx Mode with continuous wave */
    	if (HAL_SUBGHZ_ExecSetCmd(&hsubghz, RADIO_SET_TXCONTINUOUSWAVE, NULL, 0) != HAL_OK)
    	{
    		Error_Handler();
    	}
     
        while (1)
        { }
    }

    static void MX_SUBGHZ_Init(void)
    {
      hsubghz.Init.BaudratePrescaler = SUBGHZSPI_BAUDRATEPRESCALER_8;
      if (HAL_SUBGHZ_Init(&hsubghz) != HAL_OK)
      {
        Error_Handler();
      }
    }