Auto-dial Multiple PLCs using a single Serial Modem

The TOP Server Connection Sharing Plug-in (introduced in TOP Server v5.10.205.0 November 2012) can be used to auto-dial multiple devices using a single serial modem.  You will need to configure each device that you wish to auto-dial on a unique channel and define at least one phone number for each channel that will share the modem connection. This phone number will be stored in a channel-level phonebook.

Operation:

As each channel gets its turn to communicate, the modem that is associated with the connection will be initialized and asked to dial the first phone number in the phonebook that is assigned to the channel. Once the connection is established, the driver will communicate with the remote device by default. It will perform one read or write transaction depending on the requests that it has pending. Users can increase the number of transactions that are executed on each cycle through the Advanced tab located in Channel Properties. The Transactions per Cycle setting may be changed regardless of whether a modem is used; however, users that utilize a modem may be more likely to increase the transaction count in order to maximize the amount of data that is obtained for each dial attempt.

If you are using a version of TOP Server prior to v5.10.205.0, please reference this FAQ.