PLC code structuring

Hi
I'm after some suggestions.
When programming an SLC, I like to structure data tables as follows:
LAD 5
Binary B53:xx
Timers T54:xx
Integers N57:xx

LAD 6
B63:xx
Timers T64:xx
etc.
You end up with a lot of data tables, but they're generally short and it's really easy to modify the programme in the future. All our customers love it.

Does anyone have a nice way of doing something similar with Step 7, other than a piece of paper and checking off the M's when used?

Thanks

I don't know what Step 7 is. GE uses %M but I don't know GE well engough to give any ideas. By the way, do you or anyone see any reason for the % ? just an extra keystroke as far as I can see, one of the reasons i dislike GE.

But, I have been structuring AB DATA TABLES the way you are doing, and thought I was the only one. It means u have thought before writing logic, what needs to done and how to do it. The Final program can be understood by others (Maint Tech's) and Trigger a Growing insight in better PLC logic design.

Don't stop with data files, use ladder 11,12,13,14 etc.. for station 1,2, 3,4, or whatever also. Next step, you will suddenly see amazing posibilities for using INDEX AND IDIRECTED Addressing.

One can do wonders with a S7

I would not use the main memory for anything that isn't global. Most things should be put in data blocks. Another thing you can do with a S7 that a PLC/5 can't do is mix and match data types in a data block. If one has a project that has 8 axes of motion, one can create a data block for each axis that has all the infomation ( bits, bytes, integers, float etc ) for that axis. The data block can then be passed as a parameter to a function block or function. In general, each significant widget should have it own data block. To create another widget one can just create another data block.

Peter
So could I create a DB with all the memory for a function?
The obvious way is FC1 with DB1, FC2 with DB2 etc.
I remember S5 didn't like you manipulating bits within a dataword (it took ages). S7 doesn't have this problem I guess?
If you have some sample code I'd appreciate it.
Thanks