Voice Transmit on ble

RE: Voice Transmit on ble

haakonsh — Mon, 18 Jun 2018 09:08:24 GMT

What is your connection interval?
Have you enabled Data Length Extension?
Are you testing throughput with our DK or a custom board?

RE: Voice Transmit on ble

HakJae — Mon, 11 Jun 2018 04:08:12 GMT

I am sorry about my expressiveness.

I try to transmit microphone data.

So i should transmit 8000 bytes per second.

i setted the MTU size, and connection parameter as above. and i send 128 bytes each time.

Then i should be able to send more than 8000 bytes in 1 second.

but when i checked transmit speed, i could only send 4224 bytes in 1 second..

i want to improve the transmission speed.

please help me. thank you.

RE: Voice Transmit on ble

haakonsh — Thu, 31 May 2018 14:29:33 GMT

Hey HakJae,
I still do not understand what your problem is. I need you to describe your symptoms in more detail, specifically what you mean by transmission speed and receive interval.

Cheers,

Håkon.

RE: Voice Transmit on ble

HakJae — Wed, 23 May 2018 08:08:04 GMT

I set the MTU size to 247.

#define NRF_SDH_BLE_GATT_MAX_MTU_SIZE 247;

nrf_ble_gatt_data_length_set(&m_gatt, BLE_CONN_HANDLE_INVALID, NRF_SDH_BLE_GATT_MAX_MTU_SIZE + L2CAP_HDR_LEN);

RE: Voice Transmit on ble

haakonsh — Tue, 22 May 2018 10:44:48 GMT

What about MTU size and Data Length Extension?

RE: Voice Transmit on ble

HakJae — Thu, 10 May 2018 07:50:02 GMT

this is mic board, speaker board's connection parameters.

The connection parameters of 'mic board' and 'speaker board' are the same.

static ble_gap_conn_params_t const m_connection_param =
{
(uint16_t)MIN_CONNECTION_INTERVAL, // MIN_CONNECTION_INTERVAL MSEC_TO_UNITS(7.5, UNIT_1_25_MS)
(uint16_t)MAX_CONNECTION_INTERVAL, // MAX_CONNECTION_INTERVAL MSEC_TO_UNITS(30, UNIT_1_25_MS)
(uint16_t)SLAVE_LATENCY, // 0
(uint16_t)SUPERVISION_TIMEOUT // MSEC_TO_UNITS(3200, UNIT_10_MS)
};

RE: Voice Transmit on ble

haakonsh — Wed, 09 May 2018 12:12:25 GMT

"After pairing, mic board transmit microphone signal to speaker board(128Byte). But the transmission speed is slow.

I refer to thingy F/W. Thingy Board's transmission speed is 6ms or 24ms. and my mic board's transmission speed is 30ms."

Do you mean latency? If so what are your connection parameters?

RE: Voice Transmit on ble

HakJae — Sat, 05 May 2018 13:34:31 GMT

I used my cell phone to pairing on the thingy board. And i receive microphone data. In nRF Connect's log, the receive interval was repeated 6ms and 24ms. But my mic board's receive interval was 30ms. My mic board used Nordic UART Service.

RE: Voice Transmit on ble

haakonsh — Wed, 02 May 2018 13:28:08 GMT

Hey HakJae,

From sd_ble_gatts_hvx API docs:

NRF_ERROR_RESOURCES; Too many notifications queued. Wait for a BLE_GATTS_EVT_HVN_TX_COMPLETE event and retry.

[quote user=""][/quote]

After pairing, mic board transmit microphone signal to speaker board(128Byte). But the transmission speed is slow.

I refer to thingy F/W. Thingy Board's transmission speed is 6ms or 24ms. and my mic board's transmission speed is 30ms.

Do you mean latency? If so what are your connection parameters?

Cheers,

Håkon.