public uint Read(RawPDU raw)
{
uint len = raw.ReadUInt32("PDV-Length");
_pcid = raw.ReadByte("Presentation Context ID");
byte mch = raw.ReadByte("Message Control Header");
_value = raw.ReadBytes("PDV Value", (int)len - 2);
_command = (mch & 0x01) != 0;
_last = (mch & 0x02) != 0;
return len + 4;
}
