ZCOM Software Overview

Figure 1-1 “Overview of ZCOM Software Structure” presents an architectural overview of the ZCOM Subsystem.

The ZCOM application interface provides low level access to the ZCOM Subsystem. Application programs make requests via the ZCOM library routines which are then communicated to the firmware on the ACC Mux card via the HP-UX drivers.

The firmware which runs on the ACC Mux card includes the ZCOM Mux kernel software plus ZCOM protocol modules. The ZCOM protocol modules provide the protocol specific firmware that runs on the ACC Mux card.

Note that the highlighted area in Figure 1-1 “Overview of ZCOM Software Structure” shows which software components are provided by the base ZCOM Subsystem. Only protocol modules used for loopback testing, and for monitoring the health of the ACC Mux card and panel are provided with the base ZCOM Subsystem. Protocol specific modules, such as X.25, are added to the ZCOM Subsystem as separate products. The Protocol User's Guides provided with these products must be used in conjunction with this Programmer's Reference Guide when writing ZCOM application programs.

Figure 1-1 Overview of ZCOM Software Structure

Figure 1-2 “ ZCOM Subsystem Components” presents another view of the ZCOM Subsystem which includes the relationships between the various components of the ZCOM Subsystem:

Figure 1-2  ZCOM Subsystem Components

The ZCOM Subsystem is initialized by the zmon daemon which reads a memory image file and downloads appropriate firmware to the ACC Mux interface cards. The memory image file is created by running the ttgen utility on an ASCII configuration file which contains information such as what protocol will be used on the various ports of the ACC Mux cards, and protocol specific configuration.

The zmlog program is used to log error messages generated by the programs and daemons of the ZCOM Subsystem. The zmasterd daemon is used to facilitate starting up and shutting down the daemons in the ZCOM Subsystem, and to automatically recover from daemon failures.

Application programs make calls to the routines in the ZCOM application interface. The same requests that can be made programmatically can also be made interactively by using the zterm program.