I ran a test for us...
I created a debug ladder file 6 with a single unconditional rung "ADD N7:255, 1, N7:255"...
I downloaded to my emulator (RSLogix500 Emulate revision 5.00.08.00) and nothing happened to the value, it stayed at zero.
I tried to add a JSR to the debug file offline, and got an error, somethign like: can't jump to a debug file...
So, after looking in the RSLogix500 Emulate help files I learned this:
In RSLogix emulate you have to select Settings-->Emulation... from the menu bar. On that dialog box you select the debug file to be used, and get to pick the starting and ending rungs.
So, since my program was downloaed and running, I went online and changed those settings.
Still nothing happened to the value. So, I found that I had to set the emulation settings first, then download a file again to get the settings to take effect.
Then my number starting incrementing, much slower than I anticipated.
So, I opened up the settings dialog while online, and noticed that the debug file had reverted back to zero with starting rung of zero and ending rung of -1, but the emulator still appeared to be scanning the file.
I then found that I could affect the rate at which the emulator scanned the debug file by adjusting the priority slider at the bottom right of that box, but it would not take effect until I hit the OK button and closed the dialog box.
When I opened it up again, my debug file and rung numbers were back (6, 0, -1...apparently the -1 means scan the whole file)...
Yep, it is a little weird but it does seem to work...There is more info on the RSLogix500 Emulate help screens...
Paul