API Routes

Route	HTTP method	Body required	Body description	Poll via /check
/check_connection	POST	No	Discover enabled pay_system + operations	No
/showqrcode	POST	Yes	Start payment flow	Yes
/check	POST	Yes	Poll payment status	N/A
/cancel	POST	Yes	Cancel/refund flow	No
/refund	POST	Yes	Refund flow	No
/final_confirm	POST	Yes	Final confirmation/fiscal data	No

Over Serial the same routes are addressed as :8887<route>.