public async Task TestLong() { var factory = new ModbusFactory(); IModbusMaster modbus = factory.CreateMaster(_client); await _client.ConnectAsync(MODBUS_IP, MODBUS_PORT); long?data = await modbus.ReadLongAsync(MODBUS_SLAVE, 0); Assert.NotNull(data); await modbus.WriteLongAsync(MODBUS_SLAVE, 0, -2000000); data = await modbus.ReadLongAsync(MODBUS_SLAVE, 0); Assert.NotNull(data); Assert.Equal(-2000000, data); await modbus.WriteLongAsync(MODBUS_SLAVE, 0, 0); data = await modbus.ReadLongAsync(MODBUS_SLAVE, 0); Assert.NotNull(data); Assert.Equal(0, data); data = await modbus.ReadOnlyLongAsync(MODBUS_SLAVE, 0); Assert.NotNull(data); }