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We are completing the last minor systems on the Discovery Channel Telescope, and I am looking forward to the next venture, wherever it will be. My ideal next move would be to design and implement an even larger, more complex system. (The control component template I developed here and, more importantly, the concepts therein are readily scalable and directly applicable to pretty much any type of control system.) I think the DCT software system is an amazingly powerful, robust, and elegant software system! I am looking forward to building the next incredible system! res Oct 2012.docx

Hi All, I have been trying to come up with a way to make my program more efficient. I am trying to use less nested case structures, and to avoid calling sub VIs multiple times. I looked at some of the design patterns, and there was not a sole design pattern available that did what I wanted, so I have tried to combine 3 patterns into one. My application has a user interface controlling a camera, and each function is context sensitive. For example, if the camera is already acquiring images, the "change video mode" function needs to unconfigure acquisition before adjusting the settings. If the camera is not doing anything, the unconfigure step isn't necessary. My previous attempt used nested case structures to test the condition of all these criteria, and take the required action, so there were cases for every combination of states. I wanted the code to be more minimalist, and call functions (sub VIs) in a state machine in a different order, skipping certain cases, depending on the context. I wanted to combine the low CPU usage of the event structure with the queued message handler example, to take an array of states and process them one at a time. My first attempt is attached. I used notifiers because I don't want steps to be queued if the user presses multiple commands before completion. I want to only process the first command received after the current notifier changes are made. I couldn't think of a way to change between using the array from the notifier and using the modified array (minus the deleted element) in a shift register, so I used the send notification inside the slave loop to send the modified array of states. I want to know if there is a better, more efficient way of doing this, and whether there are any problems here. Thanks, James MasterSlave Events.vi