Rescue a project from a SIMATIC 300

Hello Felipe;

When you upload a program from a S7-300/400 CPU,, you have no access to symbols (of tag names) or comments (for your program rungs). These are not downloaded to the CPU mempry with the code. So, unless you have a copy of the original program, you have quite a bit of work to "rescue" the tag list. I understand from your post that yo do not have access to the original program, am I right?

You do have n HMI programmed with WinCC Flexible. What version of WinCC Flexible, WinCC Flexible 2005, 2008, 2008 SP3? And which license to you have, Compact, Standard, Advanced, or do you use a Basic panel (without license)?

If you have access to the HMI program (with WinCC Flexible) you can export the tag list to a csv file (opens in Excel) where you can see the addresses in Step 7 and where they are used in WinCC Flexible, so you can use this information to (partially) rebuild your Step 7 symbol table to rescue the PLC program.

https://support.industry.siemens.com/cs/ww/en/view/18796010/9359905803

Hope this helps,

Daniel Chartier