As you define your devices, you can verify that the configuration of the device is correct and that the communication path to the device is working in several ways.
- When defining a new device or editing an existing device definition, the Validate function verifies that the parameter values for the device are valid and performs a communication connection to the physical device.
- After using Validate, use the Save function to save the current device definition.
- Select Devices in the left pane to
view the devices defined for this node.
The devices that are defined in this node will be listed in the Devices window.
The State column shows the current state of the device: Stopped when first defined and Started after a successful start of the device. There are other states that a device can have: Starting, Stopping and Disabled when the device is transitioning between the Started and Stopped states or when recovering from a communication problem.
The following example shows a CTI 2572 Listener device
and a CTI Device device defined in the node. The CTI 2572
Listener device is in the Started state
and the CTI Device device is in the
Stopped state. 
The Start button can be used to change the
state of a device from Stopped to Started.
When a CTI 2572 Listener device is started, the driver:
- Opens up a TCP socket that will accept connections from CTI 2500 series programmable controllers.
- Sets up the internal structures to keep track of the connections established with the CTI 2500 series programmable controllers.
- Places the device in the Started state and waits for messages to arrive from the connected controllers.
When a CTI Device device is started, the driver:
- Establishes a communication connection to the physical device.
- Sets up the internal structures to keep track of the device connection.
- Places the device in the Started state, which allows the device to be accessed (read and write), by your applications.