Read Temperature from a Remote Temperature Sensor

This example shows how to read temperature and humidity measurements from a remote sensor on a PLC connected via TCP/IP. The temperature sensor is connected to a holding register at address 1 on the board, and the humidity sensor is at address 5.

Create the Modbus^® object, using TCP/IP.

m = modbus('tcpip', '192.168.2.1', 502)

m = 

   Modbus TCPIP with properties:

    DeviceAddress: '192.168.2.1'
             Port: 502
           Status: 'open'
       NumRetries: 1
          Timeout: 10 (seconds)
        ByteOrder: 'big-endian'
        WordOrder: 'big-endian'

The humidity sensor does not always respond instantly, so increase the timeout value to 20 seconds.
```
m.Timeout = 20
```
The temperature sensor is connected to a holding register at address 1 on the board. Read one value to get the current temperature reading. As the temperature value is a double, set the precision to double.
```
read(m,'holdingregs',1,1,'double')
```
```
ans = 

   46.7
```
The humidity sensor is connected to the holding register at address 5 on the board. Read one value to get the current humidity reading.
```
read(m,'holdingregs',5,1,'double')
```
```
ans = 

   35.8
```
Disconnect from the server and clear the object.
```
clear m
```