Specifications

General Purpose Interface
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You can configure a message protocol which then parses the received Monitoring Point string. You
can also define header and trailer characters in the Protocol area of the General Purpose
Interface.
Monitoring Points can also be annunciated at the monitoring station and written to the historical
journal.
Monitoring Point Message Processing
When the General Purpose Driver receives the message from the device, it does the following:
1 Parses the message and looks for poll or action responses
• If it finds a poll or action response, it processes the response
• If it does NOT find a poll or action response, it continues to parse
2 Looks for a message protocol
• If it finds a message protocol, it processes the protocol
• If it does NOT find a message protocol, it continues to parse
Note
The device can delimit the message with or without header and trailer characters
Poll Command
The Poll Command, frequency of polling and expected response (Poll Command
Acknowledgment) are all defined as part of the configuration of a specific General Purpose
Device.
Poll Command Acknowledgement
Some protocols will include an acknowledge character returned to the device that issued the
polling command - this is additional confirmation that the general purpose device received the
command.
Output
Output is performed using an Action which is activated by an Event. The output sends a string of
characters to the General Purpose Device through the serial/network port.
The optional expected response is also configured as part of the action.
Virtual Keyboard
As the ASCII characters between 0 and 32 are not visible on screen and have no equivalent
keyboard button, the virtual keyboard is relied on to enter these values. Some common values are
the STX (Start of Text) and ETX (End of Text) which have no keyboard button but can be entered
via the virtual keyboard.