multi-central limitation

RE: multi-central limitation

Avi — Fri, 22 Apr 2022 08:53:22 GMT

Problem solved by clearing the echo

#define ECHOBACK_BLE_UART_DATA 0

RE: multi-central limitation

Avi — Fri, 22 Apr 2022 08:11:45 GMT

I found the following answer few years ago related to SDK15, but the description of the problem seems similar.

https://devzone.nordicsemi.com/f/nordic-q-a/47372/ble_nus_c_evt_nus_tx_evt-has-handle-of-0xffff

I am also getting 0xffff

I am using now, SDK17.1, is there a similar fix or is it a different case?

RE: multi-central limitation

Avi — Fri, 22 Apr 2022 07:45:36 GMT

I get the following trace when I have only one client connected to the multi-central and streaming data at rate of once every 2 seconds. I don't understand why there is "Connection handle invalid". When I have more clients, there are more warnings like this and eventually, the muli-sentral cannot connect to anyone

<debug> app: Receiving data.
<debug> app: 04 00 00 00 00 00 00 04|........
<debug> app: 0B 04 28 00 00 00 00 2C|..(....,
<debug> app: 0A |.
<warning> ble_nus_c: Connection handle invalid.
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Write Request
<debug> nrf_ble_gq: SD GATT procedure (1) succeeded on connection handle: 1.
<warning> ble_nus_c: Connection handle invalid.
<warning> ble_nus_c: Connection handle invalid.
<warning> ble_nus_c: Connection handle invalid.
<debug> ble_nus_c: Client sending data.
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: Processing the request queue...

RE: multi-central limitation

Susheel Nuguru — Fri, 22 Apr 2022 07:12:31 GMT

[quote user=""]I noticed that if the data throughput is high, the multucentral device cannot handle it and crashes.[/quote]

I am assuming you are using Softdevice and not Softdevice Controller. It would be nice if you can get the context of what you mean by "crashes"? If it is a system restart, then you can

compile your application with debug version,
start the application in the debugger,
put breakpoints at NVIC_SystemReset() (grep your whole code for NVIC_SystemReset) and
run the application in the debugger until you reach the state which you mention as "crashes".

Hopefully at this point one of the breakpoints at NVIC_SystemReset will be hit and you can post the function call stack here so that we get more context on the cause of the reset.