Android Question BLE Client Content Configuration Descriptor 0x2902


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I've been working with some BLE modules that provide UART services. The first one was easy - there was a characteristic on which data was available, and setting notification on that raised an event correctly.

I'm now using a Microchip RN4020, which has a UART mode they call MLDP. It should do the same thing but setting notification the characteristic doesn't alert me.

Instead, apparently, I have to write to the Gatt Client Content Configuration Descriptor, 0x2902.

This doesn't appear listed in the characteristics or services. The thread at comes tantalisingly close to offering a solution, but I can't for the life of me see how I update this descriptor. Maybe I'm missing something obvious.

Put Claude

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;Send cmd+CR+LF
;------example to start ---------------
;Here's my RN4020 setup, this works

SF,2 ;// factory default
R,1 ;// reboot
sn,MY_4020 ;//set the BT-name for the device again.
R,1 ;// reboot
//SP,7 ;// power to the max, no need
SR,32000800 ;// auto advertise, enb mldp, peripheral,
;// cts/rts, mldp after connect, NO-IOS.
R,1 ;// reboot
ST,0064,0002,0064 ;// setup IOS required timing
R,1 ;// reboot
Can send/receive messages between Android device and PC-serial-terminal or MCU with soft-UART. Works very very well. Use it to cmd the MCU or terminal to do something and sens me messages and values...
My code is no masterpiece, You change it yourself for the best....



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