Hyperterminal comes with windows and can be installed through Control panel, add/remove programs, windows setup, communications. To open a terminal session go to start, programs, accesories, communications, hyperterminal

Enter a name of the file for the connection. The name does not matter but if you save your sessions to look at what you did make it something familiar.

On the next screen select the source of the ISDN Terminal adapter. Hyperterminal will only work with internal, serial, and usb terminal adapters. Anything that uses a communications port. If they have built in routing it should have come with a gui you could access through a internet browser or software CD. Other wise you may be able to telnet to the device.

This screen lets you setup the connection settings. The defaults should be fine. Otherwise set them as shown below.

On the white screen type in at and enter. If you get a ok but can not see what you type try ate1. Tell the customer to type it even though they can not see what they are typing. This will enable echo so that you can see what you are doing. If not try at? or check the manufacturers web site for a list of at commands.