ble_advdata_encode returns SVC Handler Missing

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I have a project that generally operates as a typical peripheral, but occassionally sends advertising packets of type BLE_GAP_ADV_TYPE_NONCONNECTABLE_NONSCANNABLE_UNDIRECTED. In the process of broadcasting these non-connectable packets, I have to call ble_advdata_encode. Usually this is not a problem, but sometimes it returns error 0x01 (SVC Handler Missing). When I look at documentation of ble_advdata_encode, it says it should return either NRF_SUCCESS, NRF_ERROR_INVALID_PARAM, or NRF_ERROR_DATA_SIZE. I'm also not picking up on any pattern that this behavior follows. Can anyone enlighten me as to what might cause  ble_advdata_encode to return error 0x01 (SVC Handler Missing)?

SDK: 15.0.0_a53641a

Soft Device: 6.0.0

IDE: Keil uVision5

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The root of the problem was in our function for broadcasting arbitrary advertising packets. It turns out that the length value in the advertising data structure in the global ble_gap_adv_data_t structure is updated with every packet to the length of that packet. If a longer packet is broadcast following a shorter packet, an error is returned. The solution was simply to update the length value for every broadcast packet. Here is what we're currently using to broadcast arbitrary advertising packets:

static ble_gap_adv_data_t m_bcast_data =	//structure that contains a pointer to encoded advertising data and the length of that data
{
	.adv_data =
	{
			.p_data = m_enc_bcast_data,
			.len    = BLE_GAP_ADV_SET_DATA_SIZE_MAX
	}
};	

/**@brief Function for broadcasting advertising packets.
 *
 * @details Provide a pointer to the packet data, provide the length of the data
 *						Function returns true when packet is sent successfully, false if tranmission fails.
 *
 * */
bool broadcast_packet( uint8_t* data, uint8_t length )
{
	bool						success = true;
	ble_advdata_t               adv_data;
	ble_gap_adv_params_t		adv_params;
	ble_advdata_manuf_data_t    mfg_data;

	//clear data structures
	memset( &adv_data, 0, sizeof(adv_data) );
	memset( &adv_params, 0, sizeof(adv_params) );
	memset( &mfg_data, 0, sizeof(mfg_data) );
	
	//global m_bcast_data.adv_data.len needs to be reset between packets
	//when a packet is sent, len is updated to the packet length (truncating any trailing zeros in the packet)
	//if a longer packet is sent after a shorter packet without updating len, ble_adv_data_enc will return 0x0C -- invalid data size
	//apparently, len is updated AFTER the size check in ble_adv_data_enc -->> manuf_specific_data_enc
	m_bcast_data.adv_data.len = BLE_GAP_ADV_SET_DATA_SIZE_MAX;	
	
	//check packet length, truncate if too long
	if( length > BROADCAST_LENGTH_MAX )
		length = BROADCAST_LENGTH_MAX;

	//configure custom data
	mfg_data.company_identifier = BROADCAST_COMPANY_ID;
	mfg_data.data.p_data = data;
	mfg_data.data.size = length;

	//point advertising data structure to custom data
	adv_data.p_manuf_specific_data = &mfg_data;

	//encode advertising data in m_bcast_data structure
	if( ble_advdata_encode( &adv_data, m_bcast_data.adv_data.p_data, &m_bcast_data.adv_data.len ) != NRF_SUCCESS )
		return !success;

	//set advertising parameters
	adv_params.primary_phy     = BLE_GAP_PHY_1MBPS;																				
	adv_params.duration        = 12;																											//Duration, in 10ms units
	adv_params.properties.type = BLE_GAP_ADV_TYPE_NONCONNECTABLE_NONSCANNABLE_UNDIRECTED;	//Broadcast packets are non-connectable, non-scannable, and undirected
	adv_params.interval        = 0x30;                                                      //Interval, in 625us units

	//stop any advertisement activity
	sd_ble_gap_adv_stop( m_adv_handle );

	//configure the packet with specified parameters
	if( sd_ble_gap_adv_set_configure(&m_adv_handle, &m_bcast_data, &adv_params) != NRF_SUCCESS )
		return !success;

	//start broadcast
	if( sd_ble_gap_adv_start( m_adv_handle, APP_BLE_CONN_CFG_TAG ) != NRF_SUCCESS )
		return !success;

	return success;
}

/*  We need to return to connectable advertising once the broadcast packet terminates
    Add this to ble_evt_handler:
    
    case BLE_GAP_EVT_ADV_SET_TERMINATED:
		if( m_conn_handle == BLE_CONN_HANDLE_INVALID )
		{
			advertising_init();
			advertising_start();
		}
		break;  */