central_uart example UART Rx can not receive all data sometimes

RE: central_uart example UART Rx can not receive all data sometimes

Jørgen Holmefjord — Fri, 12 Apr 2024 08:48:37 GMT

Hi,

There should be default configurations in the samples. I'm not aware of any specific overview of all Kconfig options specifically for BT connections. The guide you linked tries to explain the concepts and helps you determining what to configure. There is a complete Kconfig reference in the SDK documentation, but this is primarily helpful when you know exactly what you are looking for, or when you can to check what a specific Kconfig does.

Best regards,
Jørgen

RE: central_uart example UART Rx can not receive all data sometimes

Felix Shih — Wed, 27 Mar 2024 11:01:38 GMT

Hi,

There are many differences with this configuration set,

Building a Bluetooth application on nRF Connect SDK - Part 3 Optimizing the connection

2.2 NUS throughput example

How to decide which configuration is mandatory or option?

RE: central_uart example UART Rx can not receive all data sometimes

Jørgen Holmefjord — Tue, 26 Mar 2024 14:03:50 GMT

You might have to increase the data length in order to send the packets correctly. Try adding something like this to your prj.conf:

CONFIG_BT_DATA_LEN_UPDATE=y
CONFIG_BT_HCI_ACL_FLOW_CONTROL=y
CONFIG_BT_L2CAP_TX_MTU=247
CONFIG_BT_BUF_ACL_RX_SIZE=251
CONFIG_BT_CTLR=y
CONFIG_BT_CTLR_RX_BUFFERS=10
CONFIG_BT_BUF_ACL_TX_COUNT=10
CONFIG_BT_BUF_ACL_TX_SIZE=251
CONFIG_BT_CTLR_DATA_LENGTH_MAX=251

RE: central_uart example UART Rx can not receive all data sometimes

Felix Shih — Tue, 26 Mar 2024 09:19:10 GMT

Hi,

1) I update to NCS v2.6.0, so it need to use send interval less than 800ms to reproduce the issue now. If send with 800ms interval, it send a few packets normally and then show error messages, but if less than 700ms interval, it show the error messages at the first.

2) the connection interval should be default values, I don't change it.

#define BT_GAP_INIT_CONN_INT_MIN 0x0018 /* 30 ms */

#define BT_GAP_INIT_CONN_INT_MAX 0x0028 /* 50 ms */

3) I send 207 bytes from central UART to test it, the test hex value string as the following:

41542b0051c801020304050607080910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182838485868788899091929394959697989900010203040506070809101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899000a

the RTT log:

00> [00:00:00.006,896] <inf> fs_nvs: 6 Sectors of 4096 bytes
00> [00:00:00.006,927] <inf> fs_nvs: alloc wra: 0, f70
00> [00:00:00.006,927] <inf> fs_nvs: data wra: 0, 118
00> [00:00:00.007,110] <inf> bt_sdc_hci_driver: SoftDevice Controller build revision: 
00>                                             36 f0 e5 0e 87 68 48 fb  02 fd 9f 82 cc 32 e5 7b |6....hH. .....2.{
00>                                             91 b1 5c ed                                      |..\.             
00> [00:00:00.010,711] <inf> bt_hci_core: HW Platform: Nordic Semiconductor (0x0002)
00> [00:00:00.010,742] <inf> bt_hci_core: HW Variant: nRF52x (0x0002)
00> [00:00:00.010,772] <inf> bt_hci_core: Firmware: Standard Bluetooth controller (0x00) Version 54.58864 Build 1214809870
00> [00:00:00.011,413] <inf> bt_hci_core: No ID address. App must call settings_load()
00> [00:00:00.011,413] <inf> central_uart: Bluetooth initialized
00> [00:00:00.012,329] <inf> bt_hci_core: Identity: C1:69:8A:90:[00:00:13.908,386] <wrn> central_uart: NUS send timeout
00> [00:00:14.459,625] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:15.321,746] <wrn> central_uart: NUS send timeout
00> [00:00:15.862,976] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:16.725,067] <wrn> central_uart: NUS send timeout
00> [00:00:17.266,265] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:18.108,367] <wrn> central_uart: NUS send timeout
00> [00:00:18.669,586] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:19.521,697] <wrn> central_uart: NUS send timeout
00> [00:00:20.062,896] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:20.904,998] <wrn> central_uart: NUS send timeout
00> [00:00:21.466,217] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:22.308,319] <wrn> central_uart: NUS send timeout
00> [00:00:22.869,537] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:23.711,639] <wrn> central_uart: NUS send timeout
00> [00:00:24.252,868] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:25.114,959] <wrn> central_uart: NUS send timeout
00> [00:00:25.656,158] <wrn> central_uart: Failed to send data over BLE connection(err -120)

I am not sure captured the data what you need to watch, the sniffer log is as the follows.

devzone.nordicsemi.com/.../240326_5F00_NUS-send-timeout.pcapng

RE: central_uart example UART Rx can not receive all data sometimes

Jørgen Holmefjord — Mon, 25 Mar 2024 15:00:07 GMT

[quote user="Felix168"]But when I send data size to 207 bytes in 1000ms interval, the BLE failed to send data,[/quote]

Does it work for the first packets, or it never works from the first connection?

What is the connection interval for the BLE connection? Can you provide a sniffer trace?

Error -120 means "Operation already in progress".

RE: central_uart example UART Rx can not receive all data sometimes

Felix Shih — Fri, 15 Mar 2024 10:08:46 GMT

Hi,

1) 115200 8-n-1

2) use nRF52DK, its VCOM, no HW flow control

3) another serial terminal still have the same issue

4) the original unmodified NCS sample limit to 20 bytes, it happened in large data size, need to extend UART buffer and MTU.

5) I found this thread

Data Loss With Nordic Uart Service

add

CONFIG_UART_0_NRF_HW_ASYNC=y

CONFIG_UART_0_NRF_HW_ASYNC_TIMER=1

to prj.conf seem fix UART Rx issue.

But when I send data size to 207 bytes in 1000ms interval, the BLE failed to send data, and cause not run k_free() in

ble_data_sent() then UART can not k_malloc() success.

How to improve it?

00> [00:00:01.344,512] <inf> central_uart: Service discovery completed
00> [00:00:31.065,216] <wrn> central_uart: NUS send timeout
00> [00:00:31.905,487] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:33.053,070] <wrn> central_uart: NUS send timeout
00> [00:00:33.916,748] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:35.065,765] <wrn> central_uart: NUS send timeout
00> [00:00:35.915,405] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:37.058,563] <wrn> central_uart: NUS send timeout
00> [00:00:37.905,853] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:39.055,389] <wrn> central_uart: NUS send timeout
00> [00:00:39.901,641] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:41.064,086] <wrn> central_uart: NUS send timeout
00> [00:00:41.913,696] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:43.063,781] <wrn> central_uart: NUS send timeout
00> [00:00:43.912,200] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:45.060,913] <wrn> central_uart: NUS send timeout
00> [00:00:45.905,578] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:47.056,152] <wrn> central_uart: NUS send timeout
00> [00:00:47.901,214] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:49.066,131] <wrn> central_uart: NUS send timeout
00> [00:00:49.912,597] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:51.063,079] <wrn> central_uart: NUS send timeout
00> [00:00:51.912,811] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:53.058,593] <wrn> central_uart: NUS send timeout
00> [00:00:53.905,120] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:55.053,314] <wrn> central_uart: NUS send timeout
00> [00:00:55.901,123] <wrn> central_uart: Not able to allocate UART receive buffer
00> [00:00:55.901,184] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:56.914,154] <wrn> central_uart: Not able to allocate UART receive buffer
00> [00:00:57.065,704] <wrn> central_uart: NUS send timeout
00> [00:00:57.913,330] <wrn> central_uart: Not able to allocate UART receive buffer
00> [00:00:57.913,391] <wrn> central_uart: Failed to send data over BLE connection(err -120)
00> [00:00:57.963,470] <wrn> central_uart: Not able to allocate UART receive buffer
00> [00:00:58.013,580] <wrn> central_uart: Not able to allocate UART receive buffer
00> [00:00:58.063,720] <wrn> central_uart: Not able to allocate UART receive buffer
00> [00:00:58.913,940] <wrn> central_uart: Not able to allocate UART receive buffer
00> [00:00:58.964,080] <wrn> central_uart: Not able to allocate UART receive buffer
00> [00:00:59.014,190] <wrn> central_uart: Not able to allocate UART receive buffer
00> [00:00:59.064,300] <wrn> central_uart: Not able to allocate UART receive buffer
00> [00:00:59.065,124] <wrn> central_uart: NUS send timeout
00> [00:00:59.114,410] <wrn> central_uart: Not able to allocate UART receive buffer
00> [00:00:59.164,520] <wrn> central_uart: Not able to allocate UART receive buffer
00> [00:00:59.214,630] <wrn> central_uart: Not able to allocate UART receive buffer

RE: central_uart example UART Rx can not receive all data sometimes

Jørgen Holmefjord — Thu, 14 Mar 2024 15:00:59 GMT

Hi,

Which baudrate are you using? Do you have HW flow control pins enabled?

Have you tested different serial terminals on the PC to see if that makes any difference?

Are you testing with the unmodified central_uart sample? If not, what changes have you made?

Best regards,
Jørgen