HP MSR SERIES Configuration Manual page 730

Figure 732 E&M line configuration page
Table 274 Configuration items
Item
Basic Configurations
Description
Cable Type
Description
Description of the E&M line.
Select the E&M interface cable type: 4-wire or 2-wire.
By default, the cable type is 4-wire.
When you configure the cable type, make sure the cable type is the
same as that of the peer device. Otherwise, only unidirectional
voice service is available.
The configuration will be applied to all E&M interfaces of the card.
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