I am using labview to communicate with an Ethernet IO rack. Occasionally, I briefly lose the Ethernet connection to the IO rack, which shuts down the process I am controlling. If the rack does not receive a message over Ethernet every 100 mS, the watchdog on the rack shuts everything down. There are only two nodes on the Ethernet cable, the IO rack and the computer running a labview program. I am using the following NI vi’s. UDP Open, UDP Close, UDP Write and UDP Read. The computer runs windows 10 and the labview version is 15. The program is a built exe and runs 24 /7. At first I opened the port, writing, and reading data and then closing the port each iteration. This worked except that it would occasionally lose connection. It would run OK for days then there would be a shutdown. I know there are things like windows update that attempt use the Ethernet port. Is there any way I can guarantee an uninterrupted connection? Then I tried opening the port when the program starts, and keeping it open until the program shuts down. There is a bizarre undesirable behavior from time to time that I have yet to understand. Do you have any ideas of what I can do to solve this problem?
Do you want to display a number in each cell of an array or table and also independently change the background color of each cell? The table must be scrollable and the index control must work properly. It must redraw quickly. Here is a solution that meets these requirements. This method uses a cluster of a string and a color box. The string is transparent and is in front of the color box. Put this cluster in an array and wire it as shown in the diagram. This also works with numeric values. To see it work, run the vi. You are not limited to two colors. With minor code change’s you can have all the colors you want. I know of two other ways to do this but each has problems. The first method is to use a table with a property node to set the background color using nested for loops. This is very slow, typically 1 second per refresh. Setting all colors to green and then only turning the active cells red reduces that by half but this is still slow. In addition it produces a confusing flicker. The second method is to stack an array of transparent text on top of an array of color boxes. This is fast but the scrollbars and the index controls do not work properly. Test table background color.vi