BPC-simulator

Simulate time signal from BPC in China on M5ATOM and ATOM S3

Reference:
https://en.wikipedia.org/wiki/BPC_(time_signal)

Checked with CASIO LWA-M141 (5133)
https://www.casio.com/intl/support/watches/manual/?module=5133
https://www.casio.com/jp/support/watches/manual/?module=5133

PCB:
https://github.com/botanicfields/BF-018A