184 CHAPTER 5: PATH BUILDER S330 DIAGNOSTICS AND PERFORMANCE STATISTICSSetting VCM Channel LoopbacksTo set VCM channel loopbacks:1 From the VCM Loopback menu, shown earlier in Figure 158, select[2] Set Channel Loopback. You are prompted to enter a channel number.2 Enter the number of the channel for which you want to set a loopback to openthe VCM Channel Loopback menu for that channel. Figure 159 shows the VCMT1-DSX Channel Loopback menu. The VCM E1 Channel Loopback menu is thesame.Figure 159 VCM Channel Loopback Menu3 Select [1] Set Loopback. A prompt appears, listing the available types of channelloopback.4 Enter the appropriate number to select one of the following types of channelloopbacks (or no loopback):PCM Loopback — Loops digital receive to transmit toward the T1 port.PCM Packet Loopback — Loops coder output to coder input toward the T1 port,using the DSP channel PCM packet loopback.Network Packet Loopback — Loops coder input to coder output toward theATM network, using the DSP channel network packet loopback.5 Select [2] Apply Setting to Channel(s).The following prompt appears:Enter Channel (1-8):6 Enter the number(s) of the channel(s) to which you want to apply the settings toset the specified loopback for those channels. You can enter a single channel, arange of channels (for example: 4-6), or a list of channels separated by commas(for example: 4,5,6).
