The symax communications driver executes as a single user-mode process within a MacroView system. No kernel device driver is required as communications is achieved via the pcap library functionality. Note that the driver is required to run as a super user (administrator) to accept the ethernet packet interface functionality. See the figure for a diagram of the typical interaction between the driver process and the rest of a MacroView system. The subsequent table provides additional details on the components shown in the figure.
Name |
Type |
Description |
symax |
Executable Process |
The Symax 802.3 protocol communications driver. This is an enhanced MacroView PLC model driver. Refer to your MacroView documentation for additional information on PLC model drivers. |
Configuration Databases |
dBase database files |
Database files that define how the symax driver shall operate. See the Configuration Overview section for information on the configuration databases used. |
PLC Controllers or Gateways |
Hardware |
The Square-D or third party hardware and networks being communicated to. An example of a third party supplier is the Niobrara R&D Corporation that manufacture the EPE5 ethernet port expander module. |
Shared Memory |
RAM |
The standard MacroView location for the real time data. |
Semaphore |
Operating System Resource |
An operating system semaphore that is used to control access to the shared memory. |
ops, mshell, mv_histr etc |
Executable Process |
Any MacroView application that accesses data source information. As can be seen from the diagram, the symax program provides real time status information to these programs. |