Verifying BLE connection on a BCM20736S

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Anonymous
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I am working with a new PCB design using the BCM20736S. I am trying to verify that BLE communications are working between the board and a Windows 8.1 PC. I am using the 2.2.1 SDK's unmodified Heart Rate Monitor application to do this test. "Heart Rate Monitor" shows up on Windows Bluetooth scan, but I am not able to pair with the board.

Although I compile for the 20736, I understand that this same code works on the 20737 part.  So I do the following without changing the firmware.... On the same PC I am able to download the firmware onto an Anaren board (Dev Kit A20737A-MSDK1 with module base on BCM20737) and the "Heart Rate Monitor" shows up on Windows Bluetooth scan. I am then able to pair with the device without any issues.

Another symptomatic difference between these is that the BCM20736S-based device will only show up on Windows' discovery screen for 8-12 seconds.  The Anaren-based device will appear on Windows' discovery screen for 40 or more seconds.

I repeated these tests with the Speed Test and several other SDK apps, and I get the exact same results.

So is there any firmware/compiler reason that the Anaren board would work in this case, but my PCB with the BCM20736S would not pair?  Does this point towards a hardware issue on my PCB, or are there possible software reasons for this issue?

Thanks,

     Aaron

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1 Solution
Anonymous
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As far as described above, yes.

But the work around (also described above) was to use BCM920736 instead of the suggested alternative.

"speed_test-BCM920736TAG_Q32 download" - DOES NOT WORK

"speed_test-BCM920736 download" - WORKS

-Aaron

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BoonT_56
Employee
Employee
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Anonymous
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This is not a problem with the Anaren.  I have three boards with BCM20736S parts installed and none of them will communicate over the radio link when I load applications from the 2.2.1 SDK.  I need guidance on how to debug this problem, please.

Thanks in advance,

     Aaron

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Can you confirm this works on the TAG3 board that we support here on the forum?

This will give us a common "gold" platform to use for t-shooting.  We have had users in the past report that code designed for the 20736 does not run on the 20737 and vice versa, but internally, our developers are not sure how this could occur.  One or two of the users experimented with the platform files for each and ended up resolving the issue.

With the exception of the RSA libraries that are only loaded if used, the two parts are identical.

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Anonymous
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I cannot find a source for TAG3. I checked Mouser, Avnet, Digikey...

Is this the same as the board that comes with BCM92073X_LE_KIT ?   ... or point me to the source for a TAG3.

Thanks,

      Aaron

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It looks like Avnet has 130 of them in stock through their online service called Express: Order Parts Online, view Manufacturer Datasheets at Avnet Express

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Anonymous
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Ok, I have one on order.

Thanks, Aaron

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Anonymous
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I received the TAG3 board, but it turns out that it uses the BCM20737 part. I was hoping to compare my operation of the BCM20736S to a board with the same part, since that is what appears not to work in my case.

In the meantime I was able to get the stock speed_test app working on my board, but for reasons I do not understand. The app pairs and is then able to communicate fine with the provided Windows SpeedTest.exe app. The trick was that I had to setup and use a make target using BCM920736 rather than BCM920736TAG_Q32. Why would this be required?

speed_test-BCM920736 download - WORKS!

speed_test-BCM920736TAG_Q32 download - DOES NOT WORK

Any ideas why the 2nd make target would work for everything else, but not support BLE pairing and connection?

Thanks,

    Aaron

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The 20737 on the tag3 is a SoC (chip) whereas you are using the SIP module flavour on your board. How did it fail? Did you include the crystal warm-up fix?

ENTRY "PMU Crystal Warm up Time"

{

   "Crystal warm up time" = 5000

}

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IS this still an issue?

anarennavigator

aneedles

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Anonymous
Not applicable

As far as described above, yes.

But the work around (also described above) was to use BCM920736 instead of the suggested alternative.

"speed_test-BCM920736TAG_Q32 download" - DOES NOT WORK

"speed_test-BCM920736 download" - WORKS

-Aaron