Use V5SerialConnection when an application needs direct status or transfer operations without the high-level state model. 
import { V5SerialConnection } from "@v5x/serial";

const connection = new V5SerialConnection(navigator.serial);

try {
  const opened = await connection.open();
  if (!opened) throw new Error("Unable to open a compatible port");
  console.log(await connection.getSystemStatus());
} finally {
  await connection.close();
}
Important methods include getDeviceStatus, getRadioStatus, getSystemFlags, getSystemStatus, getMatchStatus, file transfers, program transfers, loadProgram, stopProgram, setMatchMode, mockTouch, and openScreen. open(use, askUser) returns true for success, false for an unusable selected port, or undefined when no port is available or selected. View source