Operaghost
Member
The Usage file tells you what has been used and what is available by using a few different letters. It uses X, W, and F depending on the address and how it is being used in the logic.
When you open the input and output files, they are by default displaying the data in a binary format. So any bit that has been used will be displayed with an "X". However, you are not likely to use the bits on an analog module which is why all the bits do not have the "X" but instead have a "." meaning that bit has not specifically been used.
Instead you will likely use the entire word. So in the usage display under the "FW" column you will likely see a "W" indicating that a word type instruction is using the entire word. It is possible that a File-type instruction could use your analog value so you might even see an "F" in there. But that is probably less likely.
Now, on that display if you change back to viewing the data and then change the radix to decimal instead of seeing the sixteen bits for each word, you would instead see the decimal value that those sixteen bits represent. Very useful for analog! Now if you click Usage you will see the "X" displaying whether the entire word/element has been used regardless of Word or File type instruction.
Like I mentioned before there are still additional gotchas. Things like indirect addressing won't show up in Usage and if you have another PLC writing to memory locations in this PLC that won't show up either.
OG
When you open the input and output files, they are by default displaying the data in a binary format. So any bit that has been used will be displayed with an "X". However, you are not likely to use the bits on an analog module which is why all the bits do not have the "X" but instead have a "." meaning that bit has not specifically been used.
Instead you will likely use the entire word. So in the usage display under the "FW" column you will likely see a "W" indicating that a word type instruction is using the entire word. It is possible that a File-type instruction could use your analog value so you might even see an "F" in there. But that is probably less likely.
Now, on that display if you change back to viewing the data and then change the radix to decimal instead of seeing the sixteen bits for each word, you would instead see the decimal value that those sixteen bits represent. Very useful for analog! Now if you click Usage you will see the "X" displaying whether the entire word/element has been used regardless of Word or File type instruction.
Like I mentioned before there are still additional gotchas. Things like indirect addressing won't show up in Usage and if you have another PLC writing to memory locations in this PLC that won't show up either.
OG