A breaking change introduced to Espressif’s ESP32 BLE library in espressif/arduino-esp32#8724 breaks compatibility with the BLE-MIDI library by lathoub, which hasn’t been updated since. This makes the code examples given that use BLE-MIDI unable to compile, such as the file MIDI-madness-BLE-keyboard-constant-sending.ino. Instead of compiling, it gives an error Compilation error: conversion from 'String' to non-scalar type 'std::string' {aka 'std::__cxx11::basic_string'} requested
This can be solved by downgrading the version of the board manager Espressif ESP32 in the Arduino IDE, for example to version 2.0.13
, in which the code compiles normally.
Screenshot showing the downgraded version 2.0.13 selected, and the code compiled without error:
