QUICKDESIGNER
ASCII Flex Protocol
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ASCII Flex Protocol
The ASCII Flex Protocol is designed to allow intelligent controllers to communicate with Quick
Panels. In the world of Programmable Logic Controllers (PLC), the protocol is nearly invisible to the
user. For example, when a pilot light is placed on a panel, a variable is assigned to it. The variable is
the name of a register in the PLC. A corresponding register in the QuickPanel is also assigned to hold
the variable data.
All of the variables for a panel are assembled into a polling list. Each variable in turn is read from the
PLC by a sequence of commands which are built into the protocol.
In the world of Intelligent Controllers, the protocol is highly visible to the user. For example, when a
NUMERIC DATA DISPLAY is placed on a panel, a variable is assigned to it. The variable is a
QuickPanel register that holds information read from the controller.
The variable for the Numeric Data Display can be associated with a polling list. Each time the variable
is polled, the sequence associated with the variable is executed. The variable could also be unsolicited,
whereby nothing happens to it until the controller sends a designated sequence.
A sequence will consist of a sequence name, a command type and one or more commands. For
example, a sequence name might be MOTOR SPEED , the first command is a SEND, and the first
command string might be SET SPEED {RF22}. The second command could be a RECEIVE, and the
command GET SPEED {RF23}.
The sequence named MOTOR SPEED must be associated with a variable. In the command string SET
SPEED {RF22}, RF22 is the variable. In the command string GET SPEED {RF23}, RF23 is the
variable. The GET SPEED variable RF23 could be assigned as the tag variable for a Numeric Data
Display.
The number of sequences and associations is limited only by the amount of memory available. See the
Appendix for a formula which will help you calculate the amount of memory used. The procedure for
creating sequences will be discussed in detail in later sections.
WARNING
When using one of the PLC protocols, you can't set the Panel Trigger tag or Watchdog tag until you've
closed down the main setup dialog at least once. Tags can't be set in the setup dialog the first time into
the dialog.
There is a similar situation with ASCII Flex protocol.
You must close down the setup dialog after you select Flex as your protocol. From then on, you
are free to do what you want in the Flex dialogs.