CC2541 Android Connection Problem

Ansgar Strother

Other Parts Discussed in Thread: CC2541

Hello,

I've been running into a very odd issue with Android devices connecting to the cc2541. The issue is that sometime but not always the android device fails to connect, or connects but fails to discover the profiles / characteristics. I have done a large amount of testing and the error seems to appear completely randomly. What makes the issue odder still is that iOS devices have no issue with connecting and discovering and work perfectly every time.

I have tested this error on my own custom hard as well as on the CC2541 dev kit with no difference in the result. The project is based off of the simpleBLEPeriheral which I have no issue connecting to. At this point the only modifications I have made to the project are to modify the profiles and interactions with I/O pins.

Any suggestions would be greatly appreciated!

over 10 years ago

0 Fredrik K over 10 years ago

TI__Guru** 106705 points

Hi Ansgar,

What Android device(s) have you tested on?

Cheers,
Fredrik

0 Ansgar Strother over 10 years ago in reply to Fredrik K

Intellectual 435 points

Samsung Note 3 running 5.0.1 works

Samsung S3 running 4.3 connection issue

Moto G running 4.4.4 connection issue

HTC 1 4.4 connection issue

0 Tim C over 10 years ago in reply to Ansgar Strother

TI__Mastermind 34660 points

Can you take a sniffer capture of the fail case?

0 Ansgar Strother over 10 years ago in reply to Tim C

Intellectual 435 points

Attached is a link to the unsuccessful android devices running 4.x and the successful iOS.

https://drive.google.com/folderview?id=0B4YAb4W-a4WUfk9Hc29iM0drWlYxLTd5VGd6bGZpTExrR3VYWHRSdjZJbWZJXzhBMnQxUHc&usp=sharing

It appears that the chip is responding to the scan requests made but the android device is failing to send out a connect request.

0 Tim C over 10 years ago in reply to Ansgar Strother

TI__Mastermind 34660 points

I do not a see a connection request sent in the Android capture. It appears that your Android device is not attempting to connect.

I would first recommend using the TI Sensor Tag App (play.google.com/.../details;hl=en) to connect to the default simpleBLEPeripheral project included with the installer to verify your setup is correct. You can then modify the simpleBLEPeripheral project as needed.

0 Ansgar Strother over 10 years ago in reply to Tim C

Intellectual 435 points

Hi Tim,

To clarify that is exactly what I have done. When I first ran into this problem I reverted back to the base project and tested on multiple devices with no connection issues. I then began adding in my changes back in without initial issue but then this issue popped up again. While Android is not calling connect something on the Firmware side is causing android not to make that call. What is the next thing that I should be looking into?

Ansgar

0 Tim C over 10 years ago in reply to Ansgar Strother

TI__Mastermind 34660 points

This is completely dependent on the Android app you are using. As mentioned above, I would recommend starting with our sample app / projects. At least attempt using the TI Sensor Tag App to connect. This way you should be able to verify that you see the device advertising and can attempt to connect to it.

0 Ansgar Strother over 10 years ago in reply to Tim C

Intellectual 435 points

After some more testing it seems like the issue boiled down to me improperly changing the adv / rsp data. For android 4.x without these fields the device would not connect. What made discovering this issue more difficult is that fact that android caches ble information. Allowing the problem to appear and disappear.

Thank you for all your help.

0 Dhaval V over 9 years ago in reply to Ansgar Strother

Genius 4470 points

Hi Ansgar,

We are facing similar kind of issue, where the peripheral device stops connecting to the Android/iPhone application. Can you please elaborate more on the 'Improperly changing Adv/rsp data' i.e. how did you resolve the issue?

Appreciate your quick reply.

Thanks,
Dhaval

0 Ansgar Strother over 9 years ago in reply to Dhaval V

Intellectual 435 points

The short answer is that I looked at the simple peripeheral example and then resued all of the adv flags that they use. A more detailed answer is looking at developer.apple.com/.../BluetoothDesignGuidelines.pdf.

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CC2541 Android Connection Problem