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No scan response from MetaWear sensor

oferorgaloferorgal
in General
Hello,

I'm developing a simple system that reads data from a MetaWear sensor and sends it via serial port to my PC.

My BLE device is BGM111 from silicon labs and i'm coding in C++.

I start my discovery process and for every device I detect I get an event called evt_le_gap_scan_response.

I am able to see all devices around me except the MetaWear devices.

Only one time I got a response from the MetaWear device but thats it.

With my Android phone I have no problem connecting to the MetaWear device.

Any idea what i'm doing wrong? Maybe MetaWear has special scan parameters I need to use?

Thanks,
Ofer. 

Comments

  • EricEric
    Are you filtering by service UUID during your ble scan?
  • oferorgaloferorgal
    no
  • MattMatt
    @Oferorgal ;

    A "Scan Response" has special meaning in BLE terminology.  It is essentially an extended 2nd advertisement so a device can communicate more about itself before being connected to.  From the context of your call back it seems that it will be called when the scan response is read from a device, but not when only the 1st advertisement is received.

    MetaWear does not use the 2nd advertisement because we can fit all of our data into the 1st, which could explain why you don't get that callback.

    I would imagine there is a different callback in that API which lets you know when the first advertisement is received.

    Cheers,
    Matt
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