private bool CheckWriteMultipleResponse(List <byte> response, MbFunctionCode fun, ushort address, int p)
{
if (response == null)
{
throw new ArgumentNullException(nameof(response));
}
CheckFunction(response, fun);
CheckModbusException(response);
var responseAddr = (ushort)((response.ElementAt(1) << 8) | response.ElementAt(2));
if (address != responseAddr)
{
throw new ArgumentException(
$"address in response ({responseAddr}) differs from address in request ({address})", nameof(address));
}
var responseCount = (ushort)((response.ElementAt(3)) | response.ElementAt(4));
if (p != responseCount)
{
throw new ArgumentException(
$"value in response ({responseCount}) differs from value in request ({p})", nameof(response));
}
return(true);
}
private bool CheckWriteSingleResponse(List <byte> response, MbFunctionCode fun, ushort address, ushort value)
{
if (response == null)
{
throw new ArgumentNullException(nameof(response));
}
CheckFunction(response, fun);
CheckModbusException(response);
var responseAddr = (ushort)((response[1] << 8) | response[2]);
if (address != responseAddr)
{
throw new ArgumentException(
$"address in response ({responseAddr}) differs from address in request ({address})", nameof(address));
}
var responseVal = (ushort)((response[3]) << 8 | response[4]);
if (value != responseVal)
{
throw new ArgumentException(
$"value in response ({responseVal}) differs from value in request ({value})", nameof(value));
}
return(true);
}
internal static List <byte> CreateReadPdu(MbFunctionCode fun, ushort address, ushort count)
{
if (count == 0)
{
throw new ArgumentOutOfRangeException("Cannot read 0 registers", nameof(count));
}
if ((fun == MbFunctionCode.ReadCoils || fun == MbFunctionCode.ReadDiscreteInputs) && count > 1968)
{
throw new ArgumentOutOfRangeException("Cannot read more than 1968 registers in one query", nameof(count));
}
if ((fun == MbFunctionCode.ReadHoldingRegisters || fun == MbFunctionCode.ReadInputRegisters) && count > 123)
{
throw new ArgumentOutOfRangeException("Cannot read more than 123 registers in one query", nameof(count));
}
return(new List <byte>(5)
{
(byte)fun,
(byte)(address >> 8),
(byte)(address & 0x00ff),
(byte)(count >> 8),
(byte)(count & 0x00ff)
});
}
private static void CheckReadResponsePduHeader(MbFunctionCode fun, int byteCountExpected, List <byte> response)
{
if (response == null)
{
throw new ArgumentNullException(nameof(response));
}
if (response.Count == 0)
{
throw new ArgumentException("Won't send empty response", nameof(response));
}
CheckFunction(response, fun);
CheckModbusException(response);
var byteCount = response[1];
if (byteCountExpected != byteCount)
{
throw new ArgumentException(
$"number of bytes in response ({byteCount}) differs from expected ({byteCountExpected})", nameof(response));
}
if (byteCount != response.Count - 2)
{
throw new ArgumentException(
$"number of bytes in response ({response.Count - 1}) differs from declared ({byteCount})", nameof(response));
}
}
private static void CheckFunction(List <byte> response, MbFunctionCode fun)
{
if ((response[0] & 0x7f) != (int)fun)
{
throw new ArgumentException(
$"function code in response ({response[0]}) differs from function call ({(int)fun})", nameof(response));
}
}
internal List <ushort> UnwrapAnalogPdu(MbFunctionCode fun, ushort count, List <byte> response)
{
var byteCountExpected = count * 2;
CheckReadResponsePduHeader(fun, byteCountExpected, response);
var ushorts = response.Skip(2).Chunk(2).Select(xs => (ushort)((xs.ElementAt(0) << 8) | xs.ElementAt(1))).ToList();
return(ushorts);
}
internal List <bool> UnwrapDiscretePdu(MbFunctionCode fun, ushort count, List <byte> response)
{
var byteCountExpected = ((count / 8) + ((count % 8 != 0) ? 1 : 0));
CheckReadResponsePduHeader(fun, byteCountExpected, response);
var bools =
response.Skip(2).SelectMany(b => Enumerable.Range(0, 8).Select(n => (b & (1 << n)) != 0)).Take(count).ToList();
return(bools);
}
