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4/12/2014 2:56 PM | |
Posts: 45 Rating: (0) |
Hello All I need urgent help I have been testing a program on the PLC sim and it is displaying strange behavior - I suspect that it will behave differently on a real PLC but I dont have one here and I urgently need to confirm. I have attached the program In the FC1 I am loading a VAR_IN_OUT and returning the DBNO. The code is designed so that the VAR_IN_OUT points to a DB address, however the customer has pointed this to a VAR_TEMP being passed into the FC1 from the calling block. In this case I would expect the DBNO to return zero. In the STL I can see that the DB1 is cleared when the VAR_IN_OUT is accessed, and ACCU1 is zero. BUT, when I transfer the DB No to the outside of the block - it gives me the number of the previously accessed DB??????????????? So this is how it works in PLC sim. Can someone please please download to a real processor to see if it still returns 10 on the output pin of FC1, or if returns zero I am desperate Thanks, Michael AttachmentTest.zip (53 Downloads) |
4/12/2014 2:57 PM | |
Posts: 45 Rating: (0) |
Pic 1 |
4/12/2014 2:57 PM | |
Posts: 45 Rating: (0) |
Pic 2 |
4/12/2014 2:59 PM | |
Posts: 45 Rating: (0) |
combined pic |
4/12/2014 4:30 PM | |
Posts: 8946 Rating: (999) |
You open DB10 and DBNO give you number 10. What is the Problem? |
4/12/2014 4:57 PM | |
Posts: 45 Rating: (0) |
When I call DBNO, 10 is no longer in the DB1 register. In STL, DBNO returns 0, however, on the outside of the FC it is 10 |
4/12/2014 9:06 PM | |
Posts: 8946 Rating: (999) |
You (full-qualified) access to operand"newitem" will update the registers. That will happen in PLCSIM as well as in a real CPU. |
4/21/2014 5:21 PM | |
Posts: 8946 Rating: (999) |
No Problem (for me). Whish you much more fun with Step7! |
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