//---------------------------------------------------------------------------------------//
protected bool AddPacket(byte[] buffer, int startIndex)
{
LCDPacket packet = CreatePacket(buffer, startIndex);
ushort calculatedCRC = CRCGenerator.GenerateCRC(buffer, startIndex, packet.DataLength + 2, CRCGenerator.CRC_SEED);
Trace.WriteLine("AddPacket(): " + packet.PacketType.ToString());
switch (packet.PacketType)
{
case LCDPacket.LCDPacketType.NORMAL_RESPONSE:
AddResponsePacket(packet);
break;
case LCDPacket.LCDPacketType.NORMAL_REPORT:
AddReportPacket(packet);
break;
case LCDPacket.LCDPacketType.ERROR_RESPONSE:
AddResponsePacket(packet);
break;
}
if (calculatedCRC != packet.CRC)
{
Trace.WriteLine("CRC ERROR!:" +
" Calculated CRC = 0x" + Convert.ToString(calculatedCRC, 16) +
" Packet CRC = 0x" + Convert.ToString(packet.CRC, 16)
);
return(false);
}
return(true);
}
//-------------------------------------------------------------------------------------------------//
private LCDPacket Send(byte packetType, byte[] data, int dataLength)
{
ushort crc;
if ((data == null && dataLength != 0) ||
(data != null && dataLength > data.Length))
{
throw new ArgumentException("bad data sent to Send");
}
//
// Create packet buffer and enter header information
//
byte[] packetBuffer = new byte[dataLength + 4];
packetBuffer[0] = packetType;
packetBuffer[1] = (byte)dataLength;
//
// Enter data if there is any
//
if (dataLength != 0)
{
Array.Copy(data, 0, packetBuffer, 2, dataLength);
}
//
// Calculate and enter the checksum into the last two bytes of the packet
//
crc = CRCGenerator.GenerateCRC(packetBuffer, dataLength + 2, CRCGenerator.CRC_SEED);
packetBuffer[2 + dataLength + 1] = (byte)(crc >> 8);
packetBuffer[2 + dataLength] = (byte)crc;
//
// Send the request and return the response
//
lock (responseSignal)
{
responsePacket = null;
// Write the packet to the serial LCD
this.SendData(packetBuffer, packetBuffer.Length);
// Wait for the response packet
if (Monitor.Wait(responseSignal, MAX_RESPONSE_TIME))
{
return(responsePacket);
}
}
return(null);
}
