Simple frequency counter, run without modification on Nucleo board, Input pin PA0, PA1, PB3. Only for STM32F4 series (Tested on Nucleo-F401RE,-F411RE and F446RE)

Dependencies:   freq_counter_STM32F4xx

see /users/kenjiArai/notebook/frequency-counters/

freq_counter.lib/shortlog@0c09d29c4cf3: not found in manifest