Chapter 2 — Installation23The IRQ and I/O Port hardware configuration is listed. Ifan error message is listed, please refer to theTroubleshooting chapter of this manual.4. In the “Own ISDN Number” box, type in the subscribernumber of your own ISDN line.5. Press “Loopback Test” to begin the diagnostic procedure.The diagnostic program will make a call from the B1channel that returns through the B2 channel. The D andB channels will be tested for line integrity.FIGURE 2-19: THE LOOPBACK TESTIf you see any error messages, please consult theTroubleshooting chapter of the manual.