CC2640R2F: Android app on newer phones fails to pair with CC2640R2

I have some problems with uploading files. 

Here are some logs, it seems that images must be jpeg and also it does not accept Wireshark logs, so there should be packed.
 pairing_failed_with_new_android_phone.pcapng.gzpairing_ok_with_old_phone.pcapng.gz

also some logs from the old CC2640 based module pairing successfully with Google Pixel 8 Pro

pairing_with_old_module_pixel_8_pro.pcapng.gz

Those can be seen as expected behavior for the new module, as there are some errors when connecting new module with and old phone. We don't need to support 10-year old phones!

It looks like the connections parameters update failure might be the reason as the log from nrfConnect upd shows that

iPhone and old Android phone is working because those are not doing that update. It was is working properly on the CC2640 module, but fails on CC2640R2 one.

Hello Maciej,

Apologies for the late replay, I was out of office.

This is a quick guide about the considerations to have regarding the migration from CC2640 to CC2640R2F. This last guide confirms that the "Connection Parameter Update Request" feature is enabled by default. From the logs, I can see what you have already pointed out, which is that the parameter GAP_UpdateLinkParamReq executed from the central (phone) is not processed correctly by the peripheral. I would have expected that after a LL_CONNECTION_PARAM_REQ, the central would have answer with a LL_CONNECTION_PARAM_RSP which contains the prefer peripheral parameters, and then a LL_REJECT_EXT_IND if not accepted by the masters.

For sanity check, could you please attempt this process using another cc26 device configured as central using the host_test_app and BTool (<SDK>\tools\blestack\btool) instead of the mobile app?

In addition, we could try disabling the LL_CONNECTION_PARAM_REQ feature to force L2CAP CONNECTION PARAMETER UPDATE REQUEST. As an example, the simple_peripheral_cc26xx example does this by default by not defining USE_LL_CONN_PARAM_UPDATE in simple_peripheral.c

BR,

David.

Hello David

Thanks for reply. First I've tried running simple_peripheral app example basing on the same stack running on launchpad and it connects with my android phone without any problem. I can see that android app does connection parameters update. Then I assume that the problem is not directly in the stack but in our app or the stack settings. I was trying to find differences between simple_peripheral and our app but haven't manage to get our app connecting properly. I've also tried BTool, which connects with CC2640R2 running our app, but it does it without connection parameter update, which is our main problem. Is there a way to trigger that using BTool?

Regards

Maciej

Just a quick update: copying parts of code that are executed when !defined (USE_LL_CONN_PARAM_UPDATE) to corresponding parts of our app solved the problem with android app not being able to update connection parameters. Looks like a good workaround.

Hello David

Yes I'm enabling HCI_LE_ReadLocalSupportedFeaturesCmd() and then handling HCI_LE_READ_LOCAL_SUPPORTED_FEATURES cmdOpcode. I'm wondering why simplePeripheralApp works regardless this settings and our app based on hostTestApp example works only with connection parameter update handled by L2CAP layer. 

Another check I did was to see what method is used by our old CC2640 based module and it looks the same in the sniffer logs as with LL_CONN_PARAM_UPDATE disabled. Makes sense as the old one works properly. Are there any knows issues or reasons why hostTestApp example configured as peripheral is not supporting this LL_CONN_PARAM_UPDATE. Or maybe we are missing something when configuring the peripheral role.

Other issue is that we are planning to BLE qualify our device basing on TI's QDID. Is there any requirement to support any of the 2 above connection parameters update methods? 

BR,

Maciej.

Hello David.

SimplePeripheral app and HostTestApp differ in that matter. There is no reference to USE_LL_CONN_PARAM_UPDATE in the original HostTestApp. I've enabled L2CAP layer connection parameter update by copying sections of code that are compiled when USE_LL_CONN_PARAM_UPDATE is not defined from SimplePeripheralApp. On the other hand I haven't found any code sections that are compiled when USE_LL_CONN_PARAM_UPDATE is defined, so I assume that Link Layer should be used as default. So if it is default why it fails on HostTestApp based FW. 

Additionally I have found another connection parameter update define named L2CAP_CONN_UPDATE within code section in peripheral.c in PROFILES directory which made me even more confused:

#if defined(L2CAP_CONN_UPDATE)
l2capParamUpdateReq_t updateReq;

updateReq.intervalMin = pConnParams->minConnInterval;
updateReq.intervalMax = pConnParams->maxConnInterval;
updateReq.slaveLatency = pConnParams->slaveLatency;
updateReq.timeoutMultiplier = pConnParams->timeoutMultiplier;

status = L2CAP_ConnParamUpdateReq(gapRole_ConnectionHandle, &updateReq, selfEntity);
#else
gapUpdateLinkParamReq_t linkParams;

linkParams.connectionHandle = gapRole_ConnectionHandle;
linkParams.intervalMin = pConnParams->minConnInterval;
linkParams.intervalMax = pConnParams->maxConnInterval;
linkParams.connLatency = pConnParams->slaveLatency;
linkParams.connTimeout = pConnParams->timeoutMultiplier;

status = GAP_UpdateLinkParamReq( &linkParams );
#endif // L2CAP_CONN_UPDATE

Would be very grateful for any suggestions.

BR

Maciej

Hello Maciej,

Sorry I missed this last post, I saw the thread has been solved but I see now not entirely. Please allow me until Monday to inspect this in more detail.

BR,

David.

Hello Maciej,

Glad to hear you have found the answer! it makes sense, thanks for sharing the details.

Best Regards,

David.