Rockwell Automation 2706-M1 MESSAGEVIEW 421 HARDWARE MANUAL - Manual (Page 71)

4–11 Running Applications
Publication 2706–816
Latched Function Keys
Latched function keys remain in a changed state after being pressed.
The latched function key returns to its original state only after a
handshake bit is set by the controller. Pressing a latched function key
twice will not toggle it on and off.
After a terminal reset or powerup, the initial state of a latch function
key is its original unlatched state.
Jog feature
Messages with enabled function keys (maintained, momentary, latch)
may have the jog feature assigned. This feature affects the operation
of the function keys.
The jog feature is not a global attribute, but specific to the individual
message. That is, a given function key may be enabled in both jog
and non-jog messages in the application.
Non-Jog Messages
Messages defined as non-jog are terminated as soon as a function
key operation is completed (the function key has been pressed and
released). For momentary function keys, this includes the hold time.
For example:
PRESS
F1 - Start Pump
F2 - Stop Pump
F3 - Sound Warning
Message is terminated after one of F1, F2, or F3 is
pressed and released and the assigned hold time expires.
Jog Messages
Messages defined as jog remain displayed (active) even after the
function key has been released. The Jog message allows you to:
•
press the same function key more than once
•
press more than one function key, if more than one is enabled for
the message.
For example:
PRESS
F1 - Start Pump
F2 - Stop Pump
F3 - Sound Warning
Message remains active after F1, F2, and F3 are
pressed and released and the assigned hold time expires.