Sending multiple data packets continuously on UART service

RE: Sending multiple data packets continuously on UART service

FormerMember — Tue, 25 Oct 2016 07:38:02 GMT

Yes, that's correct.

RE: Sending multiple data packets continuously on UART service

Anjali — Tue, 25 Oct 2016 04:31:05 GMT

I see by transmission of queued packets you meant every 20 byte packet is queued if the tx line is busy?

RE: Sending multiple data packets continuously on UART service

Anjali — Tue, 25 Oct 2016 04:30:00 GMT

I solved the bug, wasn't using BLE_EVT_xx. Thanks for your test code, it helped

RE: Sending multiple data packets continuously on UART service

FormerMember — Mon, 24 Oct 2016 13:33:41 GMT

It is not necessary to use interrupt context. I used it to leave BLE_EVT_xx context before sending more packets.

Where do you see "transmission of queued packets"?

RE: Sending multiple data packets continuously on UART service

Anjali — Mon, 24 Oct 2016 06:51:59 GMT

the code You have attached, sends strings based on interrupt it seems, is there any other alternative, or is it that I am not using interrupts, so data is not being loaded in the buffer correctly

RE: Sending multiple data packets continuously on UART service

Anjali — Mon, 24 Oct 2016 03:16:21 GMT

I get that it is not posiible to send data over 20 bytes, what if I break my string to be transmitted and use separate calls to ble_nus_string_send to send fragments of 20 bytes? And also please expalin what do you mean by "transmission of queued packets", what are the queued packets here?

RE: Sending multiple data packets continuously on UART service

FormerMember — Fri, 21 Oct 2016 14:06:40 GMT

It is not possible to send data packets longer than 20 bytes with the nRF51.

The BLE_EVT_TX_COMPLETE event will occur when the transmission of the queued packets is finished. What does your "transmit" code look like? Do you ever exit the function that is transmitting?

As you know, the maximum amount of data to transmit in a notification is 20 bytes. If you try to transmit more bytes, sd_ble_gatts_hvx(..) will return an error, and APP_ERROR_CHECK(..) will reset the chip.

For debugging you can use gdb, or perhaps it is easier to set up SEGGER embedded studio. This blog post shows how to do it.

Instead of transmitting debug info over UART, you can transmit debug info over RTT. See this devzone post for how to enable debugging over RTT.

The below example is a modified version of the ble_app_uart (SDK 12.0.0), and it shows how to test the throughput by counting upwards the data to transmit (not receiving data over UART, see data_send(..) ).

ble_app_uart_test_throughput.zip

The example should be placed in the following folder: ..\nRF5_SDK_12.0.0_12f24da\examples\ble_peripheral

Note: the example has not been through extensive testing.