Analog Trunk Cards - NT8D14 Universal Trunk Card Page 51 of 236Succession Communication Server for Enterprise 1000 Circuit Card Reference Guide— self-test status— programmed configuration status• receipt and implementation of card configuration through the card LANlink:— programming of the CODECs— enabling/disabling of individual units or entire card— programming of input/output interface control circuits foradministration of trunk interface unit operation— maintenance diagnostics— transmission pad settingsCard LAN interfaceMaintenance data is exchanged with the common equipment CPU over adedicated asynchronous serial network called the Card LAN link.The signaling and control portion of the card provides circuits that establish,supervise, and take down call connections. These circuits work with thesystem CPU to operate trunk interface circuits during calls. The circuitsreceive outgoing call signaling messages from the CPU and return incomingcall status information over the DS-30X network loop.OperationThe optional applications, features, and signaling arrangements for each uniton the universal trunk card are assigned through the Trunk AdministrationLD 14 and Trunk Route Administration LD 16 programs and/or jumper strapsettings on the card.Loop start operationLoop start operation is configured in software and is implemented in the cardthrough software download messages. When the universal trunk card is idle,it provides a high impedance toward the CO for isolation and ac (ringing)detection.Incoming callsThe alerting signal into the Succession CSE 1000 is 20 Hz (nominal) ringingsent by the CO. When an incoming call is answered, ringing is tripped when
