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8. I-Surf USB Utilities
8.3 Loopback Test Program
The loopback test program is a simple program for checking your ISDN Adapter installation and your ISDN access.
The program establishes a connection "with itself", sending data and receiving them. The data received are compared to the data sent.
This program is found in
8.3.1 Prerequisites of the Test
The following conditions must be met for the loopback test to be run:
The ISDN Adapter must be installed.
The ISDN (S0 bus) cable must be connected.
The second B channel of the S0 bus must be free, that is, no other connection may be active on the same ISDN line. Any analog device connected to the ISDN Adapter (phone, fax, modem) must be on- hook.
8.3.2 Testing Criteria and Testing Procedure
The loopback test will test the following components:
ISDN access wiring
D channel protocol setting
Hardware component function
NDIS WAN Miniport driver installation
CAPI2032.DLL installation
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