How to use the function of TI-MAC's hal_ccm.h in my application to encrypt my user data?

I have try to add SSP_CCM_Auth_Encrypt in my application.Flowing TI-MAC's MSA example,I fill param as " TRUE, 0,  nonce, M, M-length,A,A-length,key,MAC,0". after  SSP_CCM_Auth_Encrypt finish,with M is string "0123456789ABCDEF" and M-Length is 16 and  key is "0123456789ABCDEF",the output A has not been written.

what value should A-length been written?

  uint8 status = FAILURE;
  uint8 nonce[13];
  uint8 key[16];
  uint8* m =   vcom_data + 13 + 16;
  uint16 m_len = vcom_len - (13 + 16); 
  
  osal_memcpy( nonce, vcom_data, 13 );
  osal_memcpy( key, vcom_data + 13, 16 );
  //status = SSP_CCM_Auth_Encrypt (TRUE, Mval, Nonce, M, len_m, A, len_a, AesKey, MAC, ccmLVal);
  if(aesOut == NULL)
  {
    aesOut = osal_mem_alloc( m_len + 32 );
    if( aesOut )
    {
      osal_memset( aesOut, 0, m_len + 32 );
      aesLen = m_len + 32;
      ssp_HW_KeyInit( key );
      pSspAesEncrypt = sspAesEncryptHW;
      status = SSP_CCM_Auth_Encrypt (TRUE, 0, nonce, m, m_len, aesOut + 16, 128, key, aesOut, 0 );
    }
    
  }
  return status;