public void UpdateValueFromPlc()
{
var client = _connection?.PlcClient;
if (client == null)
{
return;
}
lock (_connection.PlcClient)
{
var retry = 3;
while (retry-- >= 0)
{
if (!client.Connected)
{
TronTrace.TraceWarning("No PLC connection");
client.Connect();
}
if (ReadValue())
{
return;
}
}
TronTrace.TraceError($"PlcItem.UpdateValueFromPlc failed to read {_info.Name}");
}
}
private void UpdatePlc(object value)
{
var client = _connection?.PlcClient;
if (client == null)
{
return;
}
lock (client)
{
var retry = 3;
while (retry-- >= 0)
{
if (!client.Connected)
{
TronTrace.TraceWarning("No PLC connection");
client.Connect();
}
if (WriteValue(value))
{
return;
}
}
}
TronTrace.TraceError($"PlcItem.UpdateValueFromPlc failed to write {_info.Name}");
}
public bool Connect()
{
PlcClient = new S7Client();
TronTrace.TraceInformation("PlcConnection: Connect to " + PlcAddress);
PlcClient.ConnectTo(PlcAddress, PlcRack, PlcSlot);
if (PlcClient._LastError != 0)
{
var text = PlcResult.GetResultText(PlcClient._LastError);
TronTrace.TraceError("PlcConnection: Connect FAILED : " + text);
}
return(IsConnected);
}
private bool ReadValue()
{
var client = _connection?.PlcClient;
if (client == null)
{
return(false);
}
var buffer = new byte[Math.Max(64, _info.ByteCount + 2)];
var result = client.DBRead(_info.DbNumber, _info.Offset, _info.ByteCount, buffer);
if (result != 0)
{
TronTrace.TraceError($"PlcItem.DBRead({_info.DbNumber}, {_info.Offset}) failed - {result} {PlcResult.GetResultText(result)}");
return(false);
}
switch (_info.PlcDataType)
{
case PlcDataTypes.X:
_value = S7.GetBitAt(buffer, 0, _info.Bit) ? 1 : 0;
break;
case PlcDataTypes.B:
_value = S7.GetByteAt(buffer, 0);
break;
case PlcDataTypes.INT:
_value = S7.GetIntAt(buffer, 0);
break;
case PlcDataTypes.DINT:
_value = S7.GetDIntAt(buffer, 0);
break;
case PlcDataTypes.DT:
_value = S7.GetDateTimeAt(buffer, 0);
break;
case PlcDataTypes.STRING:
_value = S7.GetStringAt(buffer, 0);
break;
}
if (!_value.Equals(_oldValue))
{
_oldValue = _value;
ValueChanged?.Invoke(this);
}
return(true);
}
public void StartPolling(List <PlcItem> items, int plcPollIntervalMilliseconds)
{
_pollItems = items;
PlcPollIntervalMilliseconds = plcPollIntervalMilliseconds;
if (PlcPollIntervalMilliseconds > 0)
{
TronTrace.TraceInformation($"PlcConnection: Start polling using {PlcPollIntervalMilliseconds}ms interval");
_pollTimer = new Timer(_ => PollPlc(), this,
TimeSpan.FromMilliseconds(PlcPollIntervalMilliseconds),
TimeSpan.FromMilliseconds(PlcPollIntervalMilliseconds));
}
}
private void DoPollPlc()
{
if (PlcClient.Connected != _oldPlcConnected)
{
TronTrace.TraceInformation("PlcConnection: Connected = " + PlcClient.Connected);
_oldPlcConnected = PlcClient.Connected;
}
foreach (var plcItem in _pollItems)
{
plcItem.UpdateValueFromPlc();
}
}
private bool WriteValue(object value)
{
var client = _connection?.PlcClient;
if (client == null)
{
return(false);
}
if (!client.Connected)
{
return(false);
}
var buffer = new byte[_info.ByteCount + 64];
_value = value ?? throw new ArgumentNullException(nameof(value));
try
{
switch (_info.PlcDataType)
{
case PlcDataTypes.X:
S7.SetBitAt(ref buffer, 0, _info.Bit, UniversalConverter.ConvertTo <bool>(_value));
break;
case PlcDataTypes.B:
S7.SetByteAt(buffer, 0, UniversalConverter.ConvertTo <byte>(_value));
break;
case PlcDataTypes.INT:
S7.SetIntAt(buffer, 0, UniversalConverter.ConvertTo <short>(_value));
break;
case PlcDataTypes.DINT:
S7.SetDIntAt(buffer, 0, UniversalConverter.ConvertTo <int>(_value));
break;
case PlcDataTypes.DT:
S7.SetDateTimeAt(buffer, 0, UniversalConverter.ConvertTo <DateTime>(_value));
break;
case PlcDataTypes.STRING:
var text = UniversalConverter.ConvertTo <string>(_value);
if (text.Length > _info.MaxStringLength)
{
text = text.Substring(0, _info.MaxStringLength);
}
S7.SetStringAt(buffer, 0, _info.MaxStringLength, text);
break;
}
var result = (_info.PlcDataType == PlcDataTypes.X)
? client.WriteArea(_info.PlcArea, _info.DbNumber, _info.Offset, _info.ByteCount, _info.PlcWordLen, buffer)
: client.DBWrite(_info.DbNumber, _info.Offset, _info.ByteCount, buffer);
if (result == 0)
{
return(true);
}
TronTrace.TraceError($"PlcItem.DBWrite({_info.DbNumber}, {_info.Offset}) failed - {result} {PlcResult.GetResultText(result)}");
}
catch (Exception ex)
{
TronTrace.TraceError($"PlcItem.DBWrite({_info.DbNumber}, {_info.Offset}) failed - {ex.Message}");
}
return(false);
}
