/// <summary>
/// Scans provided collection of frequencies against specified Squelch value.
/// </summary>
/// <param name="frequency">a collection of frequency bands which should get scanned</param>
/// <param name="threshold">Raw squelch value [0-256]</param>
/// <remarks> The block scanning automatically ends when scanned RAW signal strength value rises <see cref="G313BlockScanner.FrequencyScanned"/>the event.</remarks>
/// <returns>Returns true if the operation is started</returns>
/// <exception cref="InvalidOperationException">Cannot start when scanning is in-progress.</exception>
public bool Start(ICollection <uint> frequency, int threshold = 256)
{
if (_started)
{
throw new InvalidOperationException("block scanning already in progress");
}
_frequencies = frequency.ToArray();
_rawStrength = new uint[_frequencies.Count()];
_frequencies.CopyTo(_rawStrength, 0);
_threshold = threshold;
_gcHandle = GCHandle.Alloc(_rawStrength, GCHandleType.Pinned);
var result = G313Api.BlockScan(_parent.Handle.ToInt32(), _gcHandle.AddrOfPinnedObject(), (uint)_frequencies.Length, threshold, uint.MaxValue, IntPtr.Zero, 0);
if (!result)
{
_gcHandle.Free();
return(false);
}
_started = true;
_task = TaskUtility.Run(MonitorScan);
//_task = Task.Run(() => MonitorScan());
return(true);
}