ganutenator
Lifetime Supporting Member
I don't currently have access to a PanelView for testing and am unsure about the button operations.
I didn't find the answers to these questions in my search of this site. Doesn't mean I didn't miss it though, if someone remembers a good link....?
Momentary
If I push a momentary button that is configured for normally open with a hold time of 500ms, I am assuming that the button will write a 1 to the PLC for 500ms and then write a zero. Does the zero get written for 500ms also? What happens if you lose comms during the 500ms in which the 1 is being written? Will it act as if an operator stuck a toothpick in a real life pushbutton to keep it latched.
Maintained
The way the wording in the help file is written, it looks as if the last value is stored in the PanelView. When the button is pushed, the panelview flips the state. Is this correct?
I notice that there is an initial state setting in the terminal setup dialog, the button configuration, and the tag configuration. Which one takes precedence on power up? What is the purpose of all three?
Can the PLC unlatch a Maintained pushbutton by unlatching the write tag, thus switching the button state?
Latched
Needs a Handshake tag to unlatch the pushbutton state.
The PlC must write a 1 to the handshake tag in order to change the state of the pushbutton back to state 0. How does this Handshake tag return to a zero? Does the PanelView reset it, or must the PLC reset it? What happens if the PLC resets the write tag?
I didn't find the answers to these questions in my search of this site. Doesn't mean I didn't miss it though, if someone remembers a good link....?
Momentary
If I push a momentary button that is configured for normally open with a hold time of 500ms, I am assuming that the button will write a 1 to the PLC for 500ms and then write a zero. Does the zero get written for 500ms also? What happens if you lose comms during the 500ms in which the 1 is being written? Will it act as if an operator stuck a toothpick in a real life pushbutton to keep it latched.
Maintained
The way the wording in the help file is written, it looks as if the last value is stored in the PanelView. When the button is pushed, the panelview flips the state. Is this correct?
I notice that there is an initial state setting in the terminal setup dialog, the button configuration, and the tag configuration. Which one takes precedence on power up? What is the purpose of all three?
Can the PLC unlatch a Maintained pushbutton by unlatching the write tag, thus switching the button state?
Latched
Needs a Handshake tag to unlatch the pushbutton state.
The PlC must write a 1 to the handshake tag in order to change the state of the pushbutton back to state 0. How does this Handshake tag return to a zero? Does the PanelView reset it, or must the PLC reset it? What happens if the PLC resets the write tag?