ZCOM Subsystem

ZCOM Concepts

Figure 1-3 on page 18 shows a sample set of program and terminal ZLUs, and their interaction with each other and a Mux card:

Figure 1-3 Definition and Features of ZLUs

Terminal 2

Terminal 1

Terminal

Terminal 3

ZLU=231

 

Terminal

ZLU=57

Terminal

ZLU=101

Mux card

Program

ZLU=500

Application

Program B

Program

ZLU=502

Application

Program A

To communicate to another program or to a terminal, a program uses ZCOM library calls to write to a program or terminal ZLU. Each program ZLU points to a queue that contains all messages, including timeout and status messages, that were delivered to the program ZLU. These pointers

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Chapter 1