Modbus Plus Network Diagnostic Functions
8.2Scanning the Modbus Plus Network
Procedure for Scanning the Modbus Plus Network
Introduction | When the Diagnostics screen is first displayed, the only node that will appear in the |
| list of Modbus Plus Network nodes is the TSXCUSBMBP device itself. A Scan |
| function is used to locate other nodes on the network. |
Scanning Local or Complete Network
A scan can be done on either the local Modbus Plus network or the complete Modbus Plus network.
zWhen scanning the local network, Bridge Plus devices will be shown in the list but no scanning will be done on the second network connection on the Bridge Plus.
zWhen the complete Modbus Plus network is scanned, every Modbus Plus device accessible from the TSXCUSBMBP device will be shown.
Note: The complete network scan is performed as follows: z The system sequentially queries each address.
z The system sends a query to address 1. If a reponse is obtained, the information is displayed and the system sends a request to the next address. If the device is not connected to the network the system waits for a defined timeout period before moving on to the next address.
z Address polling may be time consuming. For example, depending on the network arcitecture (number of devices connected or disconnected) identifying 247 devices can take up to 12 minutes.
Modbus ID Field If a node displayed in the scan list has been entered into the routing table used by application software to route messages for a specific Modbus ID to that Modbus Plus node, the Modbus ID used by the application will be shown in the Modbus ID field for that node.
42 | 35011984 02/2006 |