989NTBK51 Downloadable D-channelHandler daughterboardContents This section contains information on the following topics:"Functional description" (page 1003)"Physical description" (page 990)"Functional description" (page 992)"Download operation" (page 996)Introduction The NTBK51 daughterboard provides Downloadable D-channel Handler(DDCH) interfaces based on the Multipurpose Serial Data Link (MSDL).The DDCH provides a single purpose full-duplex serial port capable ofdownloading the D-channel application and base software into the card.TheNTBK51 provides Downloadable D-channel handler (DDCH) interfacesbased on the Multipurpose Serial Data Link (MSDL). The DDCH provides asingle purpose full-duplex serial port capable of downloading the D-channelapplication and base software into the card.The NTBK51 daughterboard provides Downloadable D-channel Handler(DDCH) interfaces based on the Multipurpose Serial Data Link (MSDL).The DDCH provides a single purpose full-duplex serial port capable ofdownloading the D-channel application and base software into the card.The NTBK51 provides the following features and functions:• ISDN D-channel related protocol• Selftest• Loopback• D-channel loadware including:— management and maintenanceNortel Communication Server 1000Circuit Card ReferenceNN43001-311 01.04 StandardRelease 5.0 23 May 2008Copyright © 2003-2008, Nortel Networks.
