private void writeInputValues() { int NbItemsToSend = Math.Min(8, listBox2.Items.Count); if (NbItemsToSend > 0) { Int16[] testValues = new Int16[NbItemsToSend]; int idx = 0; for (idx = 0; idx < NbItemsToSend; idx++) { Int16 temp = (Int16)listBox2.Items[idx]; testValues[idx] = unchecked ((Int16)temp); } try { ModbusMaster1.ModbusRequestWrite(1, 16, testValues); } catch (Exception ex) { MessageBox.Show(ex.Message); } } }