platform-teensy-gcc10/examples/mbed-serial/platformio.ini

; PlatformIO Project Configuration File
;
;   Build options: build flags, source filter, extra scripting
;   Upload options: custom port, speed and extra flags
;   Library options: dependencies, extra library storages
;
; Please visit documentation for the other options and examples
; http://docs.platformio.org/page/projectconf.html

[env:teensy31]
platform = teensy
framework = mbed
board = teensy31