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How to read notifications on RX characterstics of nrf_UART service using Gatttool

Hi All,

I need to read the data written on RX characterstics of nrf_uart Service from my board using bluez. I'm using interactive mode of gatttool with my Nordic sensor. On Bluez, I was able to get following info :

############################################ [CON][DB:A0:0D:29:AD:1A][LE]>primary

attr handle: 0x0001, end grp handle: 0x0007 uuid: 00001800-0000-1000-8000-00805f9b34fb

attr handle: 0x0008, end grp handle: 0x000b uuid: 00001801-0000-1000-8000-00805f9b34fb

attr handle: 0x000c, end grp handle: 0xffff uuid: 6e400001-b5a3-f393-e0a9-e50e24dcca9e

[CON][DB:A0:0D:29:AD:1A][LE]>chaarcteristics

handle: 0x0002, char properties: 0x0a, char value handle: 0x0003, uuid: 00002a00-0000-1000-8000-00805f9b34fb

handle: 0x0004, char properties: 0x02, char value handle: 0x0005, uuid: 00002a01-0000-1000-8000-00805f9b34fb

handle: 0x0006, char properties: 0x02, char value handle: 0x0007, uuid: 00002a04-0000-1000-8000-00805f9b34fb

handle: 0x0009, char properties: 0x20, char value handle: 0x000a, uuid: 00002a05-0000-1000-8000-00805f9b34fb

handle: 0x000d, char properties: 0x10, char value handle: 0x000e, uuid: 6e400003-b5a3-f393-e0a9-e50e24dcca9e

handle: 0x0010, char properties: 0x0c, char value handle: 0x0011, uuid: 6e400002-b5a3-f393-e0a9-e50e24dcca9e

[CON][DB:A0:0D:29:AD:1A][LE]>char-desc handle: 0x0001, uuid: 2800

handle: 0x0002, uuid: 2803

handle: 0x0003, uuid: 2a00

handle: 0x0004, uuid: 2803

handle: 0x0005, uuid: 2a01

[CON][DB:A0:0D:29:AD:1A][LE]> char-read-uuid 2902

[CON][DB:A0:0D:29:AD:1A][LE]> handle: 0x000b value: 00 00

handle: 0x000f value: 00 00

############################################

We have made very few chanegs in UUID's but RX_CHARCTERSTICS = 0x0003 remains same.

Can anyone please let me know which handle shall i read to get the data from Nordic uart service, I;ve verififed that the data is sent on RX using nrf_uart App.

Please let me know your suggestions.

Thanks Brajesh

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  • I got it myself.

    I had to see type char-read-uuid 2902. that gave me a list of all CCC (Client Characteristic Configuration) attributes on the device. i set one of them to 0100 and You can try setting them all to 0100 to get notifications if in case you'r not sure about the correct CCCD handle. then listeninig on 0x000e gave me data.

    Thanks

Reply
  • I got it myself.

    I had to see type char-read-uuid 2902. that gave me a list of all CCC (Client Characteristic Configuration) attributes on the device. i set one of them to 0100 and You can try setting them all to 0100 to get notifications if in case you'r not sure about the correct CCCD handle. then listeninig on 0x000e gave me data.

    Thanks

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