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nkolban / esp32-snippets

Sample ESP32 snippets and code fragments
https://leanpub.com/kolban-ESP32
Apache License 2.0
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BLE_client receiving data #563

Open haarislabs opened 6 years ago

haarislabs commented 6 years ago

I have an Esp-Wroom-32 and nrf52832. I'm trying to establish a ble connection between using the esp-32 as client/central and nrf52832 as server/peripheral. In BLE_client example I'm just changing the UUID of service and characteristics. static BLEUUID serviceUUID("f3641400-00b0-4240-ba50-05ca45bf8abc"); // The characteristic of the remote service we are interested in. static BLEUUID charUUID("f3641401-00b0-4240-ba50-05ca45bf8abc"); In nordic I'm using this example : https://github.com/bjornspockeli/custom_ble_service_example The problem is im not able to receive any data from nordic. It shows me BT: bta_gattc_cmpl_cback unknown conn_id = 3, ignore data That error. For a better insight of what's going on : https://pastebin.com/raw/TXZdH21T I'm new to this so any kind of guidance will be helpful

chegewara commented 6 years ago

Arduino or esp-idf example?

haarislabs commented 6 years ago

Arduino IDE

Update : I tried connecting the nrf52832 with my mobile using the nRF Connect App and I'm receiving the data fine over it.

chegewara commented 6 years ago

You code works, you are connected to nrf52832. This is where you are: https://github.com/nkolban/esp32-snippets/blob/master/cpp_utils/tests/BLETests/Arduino/BLE_client/BLE_client.ino#L125-L131 Now instead writing to characteristic try to read from it and print value to serial: https://github.com/nkolban/esp32-snippets/blob/master/cpp_utils/BLERemoteCharacteristic.h#L43-L46

haarislabs commented 6 years ago

I tried using this but it shows nothing on the serial monitor std::string value = pRemoteCharacteristic->readValue(); Serial.print("The characteristic value was: "); Serial.println(value.c_str());

I basically replaced https://github.com/nkolban/esp32-snippets/blob/master/cpp_utils/tests/BLETests/Arduino/BLE_client/BLE_client.ino#L125-L131 with the above

chegewara commented 6 years ago

Probably because value you read is not printable character: The characteristic value was:  Try to read int.

haarislabs commented 6 years ago

Thanks that worked but I'm still not getting into the "notifyCallback()" function. Why do I have to read in the main loop everytime ?

chegewara commented 6 years ago

You dont have to if peripheral is sending notifications. There is workaround for that, search this repo issues for answer.

techno94 commented 6 years ago

hello : haarislabs

here the code of the server : https://pastebin.com/bVtAUSxJ

here the code of the client : https://pastebin.com/Sveg8Lgc

cf : https://github.com/nkolban/esp32-snippets/issues/557

but i don' t arrived the client to send data to the server. it send data on the CHARACTERISTIC_UUID_RX but i want to send data to the CHARACTERISTIC_UUID_TX