HMI Client Libraries:
Overview
The HMI Client Libraries are Javascript libraries which are included in
HMI web pages to enable continuous communications with the HMI server, and
to enable control of the input and output HMI widget devices. The web page
templates provided automatically import these libraries, but if you create
your own web page templates you will need to import these libraries yourself.
Libraries
- HMI Client Protocol Library
- This library is responsible for handling all communications between the
HMI web browser (client) and the HMI server. In addition, it maintains the
"display list" which is responsible for calling the display objects and
updating them with new data as it becomes available. In addition, input
device widgets will use functions in this library to send their data to the
server.
- HMI Client Display Library
- The client display library provides a series of code objects which are
used to update the web browser SVG to reflect the state of the protocol
"tags" they are monitoring. The protocol library will scan through the list
of code objects in use and update them whenever new data arrives.
Each library object performs a specific function which emulates such
things as pilot lights, numeric outputs, gauge readings, etc. These
functions are named in a manner which reflects their use in such
familiar devices. However, their use is not limited to the provided SVG
clip-art and user created clip art can also be animated with these
functions.
- HMI Client Event and Alarm Library
- The client even and alarm library is used to display alarms and events
in HTML tables. The web page templates already come with the necessary HTML
structures and calls to the libraries to handle alarms and events. User
created custom web pages can also make use of this library.