/Users/mutoh/Library/Arduino15/packages/esp32/tools/riscv32-esp-elf-gcc/esp-2021r2-patch5-8.4.0/bin/../lib/gcc/riscv32-esp-elf/8.4.0/../../../../riscv32-esp-elf/bin/ld: sketch/main.cpp.o: in function `playToneTask(void*)':
/Volumes/mutoh/work/github/XIAOGYANbitLess/src/main.cpp:580: undefined reference to `XiaogyanClass::speaker'
/Users/mutoh/Library/Arduino15/packages/esp32/tools/riscv32-esp-elf-gcc/esp-2021r2-patch5-8.4.0/bin/../lib/gcc/riscv32-esp-elf/8.4.0/../../../../riscv32-esp-elf/bin/ld: /Volumes/mutoh/work/github/XIAOGYANbitLess/src/main.cpp:580: undefined reference to `XiaogyanClass::speaker'
/Users/mutoh/Library/Arduino15/packages/esp32/tools/riscv32-esp-elf-gcc/esp-2021r2-patch5-8.4.0/bin/../lib/gcc/riscv32-esp-elf/8.4.0/../../../../riscv32-esp-elf/bin/ld: /Volumes/mutoh/work/github/XIAOGYANbitLess/src/main.cpp:581: undefined reference to `XiaogyanClass::speaker'
collect2: error: ld returned 1 exit status
Multiple libraries were found for "BLEDevice.h"
Used: /Users/mutoh/Library/Arduino15/packages/esp32/hardware/esp32/2.0.8/libraries/BLE
Not used: /Users/mutoh/Documents/Arduino/libraries/Seeed_Arduino_rpcBLE
exit status 1
Compilation error: exit status 1
xiaogyan_arduinoでコンパイルエラーが発生する。
Ref. #46