4/15/2010 4:21 PM | |
Posts: 100 Rating: (2) |
Hi to all, I am using s7-300 CPU313C(6ES7 313-5BF03-0AB0). In my program if i try to switch on some memory bit, it will not be ON. example(M80.0 inFC9). instead of M80.0 when i use another address(M48.0) its working.I change all M80.0 to M48.0. I try to switch on from Variable table also. I have attached the snapshot and program copy below. could anybody help me please. Regards, L.V.Sundar AttachmentMemory_bit.zip (44 Downloads) |
4/17/2010 11:31 AM | |
Joined: 10/7/2005 Last visit: 4/18/2024 Posts: 3003 Rating: (1046)
|
That is correct dear sundar(note that overlapping access can be deliberately donethoughand is by itself not neccessarily an indication for incorrect programming).
Note that additionally you'll also create overlapping access if you use any of the following: MB100, MB101 MW99, MW100, MW101 MD97, MD98, MD99, MD100, MD101
That is correct too and as above there's a number of more MB, MW and MD addressesthat can create overlapping access. Apart from ticking the "Overlapping access to memory area" checkbox in the "Go to location" window, there is another nice and easy way to quickly identify all overlapping accesses. Start by displaying the Cross Rreference list (Siimatic Manager Options menu -> Reference data -> display), thenswitch the View to "Assignment" and you'll see"B", "W" and "D" columns with blue lines in it wherever "Byte" ,"Word" or Doubleword" access takes place for I, Q and M areas. I hope this helps |
Cheers |
|
Follow us on