public static TransmitFrame TransmitFrameBuild(Station stl, Station.CommandResponse cmdResp, Int32 pfBit, FrameTypes frameType, Byte[] buf)
{
//
// Build AX25 frames
//
Int32 doBufLen = 0;
if (buf != null)
{
doBufLen = buf.Length;
}
TransmitFrame transmitFrame = new TransmitFrame();
Byte[] stlB = stl.GetStationAddresBuffer(cmdResp);
transmitFrame.ibuf = new Byte[stlB.Length + 1 + doBufLen];
transmitFrame.frameType = frameType;
transmitFrame.pfBit = pfBit;
transmitFrame.seqNumMode = SequenceNumberMode.Mod8;
transmitFrame.cmdOctetPtr = stlB.Length;
if (cmdResp.Equals(Station.CommandResponse.DoCommand) && pfBit == 1) // (JNW Jan15)
{
transmitFrame.AckModeID = 0xff; // Use ackmode if enabled (JNW Jan15)
}
stlB.CopyTo(transmitFrame.ibuf, 0); // Load station address fields
transmitFrame.ibuf[stlB.Length] = (Byte)(((Int32)frameType) | (pfBit << 4));
if (doBufLen > 0)
{
buf.CopyTo(transmitFrame.ibuf, stlB.Length + 1);
}
return(transmitFrame);
}
const Byte TEST = 0xe3; // Test
//
// General purpose frame encoder
//
public static TransmitFrame TransmitFrameBuild(Station stl, Station.CommandResponse cmdResp, Int32 pfBit, FrameTypes frameType)
{
return(TransmitFrameBuild(stl, cmdResp, pfBit, frameType, null));
}
public static TransmitFrame Encode(Station stl, Connection.ConnectionParameterBuf cBuf, Station.CommandResponse cmdResp, Int32 pfBit)
{
//
// Build the XID frame to send
//
TransmitFrame commandFrame = new TransmitFrame();
Byte[] stlB = stl.GetStationAddresBuffer(cmdResp);
Int32 ptr = stlB.Length;
Int32 t;
Int32 c;
Int32 paramPtr = 0;
Byte[] tmpP = new Byte[30];
commandFrame.ibuf = new Byte[tmpP.Length + stlB.Length]; // overallocate buffer space to handle worst case. We'll trim later
commandFrame.frameType = FrameTypes.XIDType;
commandFrame.seqNumMode = SequenceNumberMode.Mod8;
commandFrame.cmdOctetPtr = stlB.Length;
stlB.CopyTo(commandFrame.ibuf, 0); // Load station address fields
commandFrame.ibuf[ptr++] = (Byte)(((Int32)FrameTypes.XIDType) | (pfBit << 4));
commandFrame.ibuf[ptr++] = (Byte)(FormatIdentifier.GeneralPurposeXIDInfo);
commandFrame.ibuf[ptr++] = (Byte)(GroupIdentifier.ParameterNegotiation);
//
// Load parameters to negotiate
//
t = (Int32)ClassOfProcedures.BalancedABMHalfDup;
tmpP[paramPtr++] = (Byte)(ParameterIndicator.ClassOfProcedures);
tmpP[paramPtr++] = (Byte)2;
tmpP[paramPtr++] = (Byte)((t >> 8) & 0xff);
tmpP[paramPtr++] = (Byte)(t & 0x7f);
tmpP[paramPtr++] = (Byte)(ParameterIndicator.HDLCOptionalParams);
tmpP[paramPtr++] = (Byte)3;
tmpP[paramPtr++] = (Byte)(cBuf.optionalFuncByte0);
tmpP[paramPtr++] = (Byte)(cBuf.optionalFuncByte1);
tmpP[paramPtr++] = (Byte)(cBuf.optionalFuncByte2);
//
// The IFrame size specified here is in bits. Check to see how many bytes we'll need to specify
//
tmpP[paramPtr++] = (Byte)(ParameterIndicator.RXIFieldLen);
c = cBuf.maxIFrame * 8;
if (c >= 65536)
{
//
// Need 4 bytes to specify the window size
//
tmpP[paramPtr++] = (Byte)4;
tmpP[paramPtr++] = (Byte)((c >> 24) & 0xff);
tmpP[paramPtr++] = (Byte)((c >> 16) & 0xff);
}
else
{
//
// Need only 2 bytes
//
tmpP[paramPtr++] = (Byte)2;
}
tmpP[paramPtr++] = (Byte)((c >> 8) & 0xff);
tmpP[paramPtr++] = (Byte)(c & 0xff);
tmpP[paramPtr++] = (Byte)(ParameterIndicator.RXWindowSize);
tmpP[paramPtr++] = (Byte)1;
tmpP[paramPtr++] = (Byte)(cBuf.maxWindowSize & 0xff);
//
// The Ack timer is specified in mSec. Check to see how many bytes we'll need
//
tmpP[paramPtr++] = (Byte)(ParameterIndicator.AckTimer);
if (cBuf.ackTimer >= 65536)
{
//
// Need 4 bytes to specify ack timer
//
tmpP[paramPtr++] = (Byte)4;
tmpP[paramPtr++] = (Byte)((cBuf.ackTimer >> 24) & 0xff);
tmpP[paramPtr++] = (Byte)((cBuf.ackTimer >> 16) & 0xff);
}
else
{
//
// Need only 2 bytes
//
tmpP[paramPtr++] = (Byte)2;
}
tmpP[paramPtr++] = (Byte)((cBuf.ackTimer >> 8) & 0xff);
tmpP[paramPtr++] = (Byte)(cBuf.ackTimer & 0xff);
tmpP[paramPtr++] = (Byte)(ParameterIndicator.NumRetries);
tmpP[paramPtr++] = (Byte)1;
tmpP[paramPtr++] = (Byte)(cBuf.maxRetry & 0xff);
tmpP = Support.PackByte(tmpP, 0, paramPtr); // Pack it down
//
// Add parameter length field to buffer
//
commandFrame.ibuf[ptr++] = (Byte)((tmpP.Length >> 8) & 0xff);
commandFrame.ibuf[ptr++] = (Byte)(tmpP.Length & 0xff);
//
// Add the parameters to the buffer
//
tmpP.CopyTo(commandFrame.ibuf, ptr);
ptr += tmpP.Length;
commandFrame.ibuf = Support.PackByte(commandFrame.ibuf, 0, ptr); //Pack it down
return(commandFrame);
}
