Posted 12 Nov 2011 This question has to do with the "Control List Selector" I have screen with a list of source tanks and a list of destination tanks and a confirm buitton. You scroll to select the source tank and hit enter to send the value to the PLC You then scroll to select the destination tank and hit enter to send the value to the PLC You hit a confirm button to go to the tank control screen and there you continue the process. When the process is finished and the operator returns to the tank selection screen the previous selections are still enabled. I'd like to have a NULL tank selection on each list so that when the process is finished it sets the list selectors to the Null tank selection. This forces the operator to select the proper combination. If he hits the confirm button before selecting the proper tanks it won't let him change screens. Is this posssible? How would you do it? Thanks for your time. Share this post Link to post Share on other sites
Posted 12 Nov 2011 Set the visibility attribute such that it doesn't appear if either of the selections is still 'null'. Share this post Link to post Share on other sites
Posted 12 Nov 2011 (edited) I am not sure of the terminology with FTViewME, but with PB32 it was called a piloted control list, in which you could set a bit to allow the PLC to take control of the displayed state of the object. You could do this temporarily, or mask out individual items ona hte list if I recall correctly. I want to say a regular FTView Multistate object will handle this just fine, you just write your null value (0 or -1 or -32767 or 999 or whatever you designate to be the error value) from the PLC whenever the process completes. This may mean segregating PLC control logic from HMI data entry tags if they are not properly mapped (a common and poor practice with FT direct references IMHO). http://www.plctalk.net/qanda/showthread.php?t=16540 Edited 12 Nov 2011 by OkiePC Share this post Link to post Share on other sites
Posted 13 Nov 2011 (edited) Not really When the process is finished I want the plc to reset the control list to the null tank selection. Now when the operator goes to that screen later on, both control list selectors are indicating Null tank selection and not the tanks that he previous selected. Edited 13 Nov 2011 by enigma Share this post Link to post Share on other sites
Posted 13 Nov 2011 Are you saying that you have it working now? Share this post Link to post Share on other sites
Posted 13 Nov 2011 No . I'm still trying to find out if it is possible for the PLC to affect the control list selector. Maybe I'm not conveying what I would like to do properly. Share this post Link to post Share on other sites
Posted 14 Nov 2011 After finally setting up the emulator and getting it to work, it seems that by writing a valid value to the control list selector tag (From the PLC), it sets the selector to the value written to it. Which means I can control its position within the control list. Now to test in real world scenario. Thanks for your time and patience Share this post Link to post Share on other sites