writeReport method

Future<void> writeReport(Uint8List buffer)

Write an Output report to a HID device.

The first byte of buffer must contain the Report ID. For devices which only support a single report, this must be set to 0x0. The remaining bytes contain the report data. Since the Report ID is mandatory, calls to writeReport() will always contain one more byte than the report contains. For example, if a hid report is 16 bytes long, 17 bytes must be passed to writeReport(), the Report ID (or 0x0, for devices with a single report), followed by the report data (16 bytes). In this example, the length passed in would be 17.

writeReport() will send the data on the first OUT endpoint, if one exists. If it does not, it will send the data through the Control Endpoint (Endpoint 0).

If the write fails this function will throw an exception.

Implementation

Future<void> writeReport(Uint8List buffer) async {
  var responsePort = ReceivePort();
  commandPort.send(USBIsolateCommand(responsePort.sendPort,
      USBDeviceCommand.writeReport, buffer, null));
  var resp = await responsePort.first as USBIsolateResponse;
  if (resp.status != USBDeviceStatus.ok) {
    throw Exception("Error writing to device: ${resp.errorMsg}");
  }
}