Maybe I get some attention when I post this here. Its more than 1.5 months ago since I reported this with the location where the problem is and nothing has happened to address this. Issue link: https://github.com/espressif/esp-idf/issues/771 My client performs a long write. When I try to read the at...

You need to create a mapping between your characteristic and the handle in the ESP_GATTS_CREAT_ATTR_TAB_EVT event.
The indices in param->add_attr_tab.handles[index] are the same that you passed with esp_ble_gatts_create_attr_tab.

Increasing the MTU size on android requires version 21+ (Lollipop - 5.0)

The related API is https://developer.android.com/reference ... stMtu(int)

I use https://github.com/espressif/esp-idf/bl ... s/base64.h which has its implementation in https://github.com/espressif/esp-idf/bl ... y/base64.c
Works for me so far.

This API might be a clue ... http://esp-idf.readthedocs.io/en/latest/api-reference/bluetooth/esp_gattc.html#_CPPv224esp_ble_gattc_config_mtu13esp_gatt_if_t8uint16_t8uint16_t This should have an effect if the the client request an MTU size increase. All files that contain gattc instead of gatts are ...

I don't know if there's a way to force this from the server. My research related to android clients tells me so far that the MTU size is hard coded at least for older devices and can not be changed. What I use so far is the auto response with the service table. The ESP-IDF SDK is in this mode able t...

The constant you mentioned is used by the gatt client not the server.

Theoretically the client can request an increase of the MTU size, but I never tested it.

See https://esp32.com/viewtopic.php?f=18&t=2448

There as been a question about this topic in https://esp32.com/viewtopic.php?f=2&t=2436 My approach of how to develop and test reusable components independently of an application might of interest for other developers. I created simple example as demonstration located at https://github.com/mh-dev/es...

I have a project that contains all my own components structured in the following way. Project dir components component1 component2 unity copy of https://github.com/espressif/esp-idf/tree/master/tools/unit-test-app/components/unity main copy of https://github.com/espressif/esp-idf/tree/master/tools/u...