ZCOM Tables and Data Structures

Physical Terminal Tables

This field contains the firmware terminal number this terminal ZLU is associated with. The firmware manages terminals using a terminal number while the ZCOM subsystem manages terminals using ZLUs on the host. On 2/8-channel cards, the terminal number must be unique for a given port. On E1/T1 cards, the terminal number is unique per card.

SUBCH - Subchannel number within port

This field contains the subchannel this terminal ZLU is configured on. If the card does not support subchannels, this field is set to zero.

PTZPRCVR - ZCOM address of primary receiver

Node number, ZLU, and checksum used as the destination address for normal messages and unsolicited status messages received for this physical terminal. This field is set by the zset_rcvr call (mode 0 or mode 1 if multiplexed terminal).

PTZPCTL_RCVR - ZCOM address of primary control receiver

This is the node number, ZLU, and checksum used as the destination address for any control input messages received for this terminal. This field is set by a zset_rcvr mode 3 call. The control input messages are distinguished by the protocol modules on the MUX, by setting bit 1 of the input message tag byte.

PTZSHRCVRS - Pointer to a linked list of shared receivers

This field contains a pointer to a linked list of programs that wish to receive normal messages and unsolicited status messages from this physical terminal. Each entry in the linked list contains the node number, ZLU, and checksum of the application which will be used as the destination address for normal messages and unsolicited status messages received from this physical terminal. This field is set by the zset_rcvr call (mode 0 or mode 1 if multiplexed terminal). If there are no shared receivers, this field will contain a zero. When a data or status message arrives, it will be delivered to each application in the linked list (as well any primary receiver).

PTZSHCTLRCVRS - Pointer to a linked list of shared control receivers

This field contains a pointer to a linked list of programs that wish to receive control messages from this physical terminal. Each entry in the linked list contains the node number, ZLU, and checksum used as the destination address for any control input messages received for this terminal. This field is set by a zset_rcvr mode 3 call. The control input messages are distinguished by the protocol modules on the MUX, by

Chapter 3

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