open method
Implementation
Future<OpenUSBDevice> open({int maxBufferLength = 256}) async {
var responsePort = ReceivePort();
Isolate.spawn(
usbIsolate,
USBIsolateInit(
responsePort.sendPort, vendorId, productId, maxBufferLength));
var commandPort = await responsePort.first;
if (commandPort is SendPort) {
return OpenUSBDevice(commandPort, this);
} else {
var resp = commandPort as USBIsolateResponse;
throw Exception("Error closing device: ${resp.errorMsg}");
}
}