public int SetPlcDateTime(DateTime DateTime) { int Length; LastError = 0; S7.SetDateAt(S7_SET_DT, 31, DateTime); SendPacket(S7_SET_DT); if (LastError == 0) { Length = RecvIsoPacket(); if (Length > 30) // the minimum expected { if (S7.GetWordAt(PDU, 27) != 0) { LastError = errS7FunctionError; } } else { LastError = errS7InvalidPDU; } } return(LastError); }