Overview Page 51 of 906Circuit Card Description and Installation• In order to detect distant end disconnect for calls terminating on thelineside T1 card, the hook flash feature within the SAL software must beenabled.• In order to detect distant end disconnect for calls originating andterminating on the lineside T1 card, both the battery reversal and hookflash features must be enabled within the SAL software.Call disconnect from lineside T1 terminal equipmentAlternatively, while a call is in process, the terminal equipment maydisconnect by going on-hook. The terminal equipment detects no loop currentand sends signaling to the lineside T1 card that causes its receive A bit tochange from 1 to 0. The call is now released.Table 4 outlines the lineside T1’s A and B bit settings in each state of callprocessing.Table 4Loop Start Call Processing A/B Bit Settings (Part 1 of 2)StateTransmit ReceiveA B A BIdle 0 1 0 1Incoming Calls:• Idle 0 1 0 1• Ringing is applied from lineside T1 card 0 1/0 0 1• Terminal equipment goes off-hook 0 1/0 1 1• Lineside T1 card stops ringing 0 1 1 1Outgoing Calls:• Idle 0 1 0 1• Terminal equipment goes off-hook 0 1 1 1Call Disconnect from far end:
