Over the 12-year history of the SLC-500 controllers there have been a few instances where status table or data table conditions were allowed by some compilers (especially in the days where there were 3rd party compilers) but were not allowed by later, more strict compilers. When a newer (or sometimes Buggy) compiler attempts to *de*compile that "illegal" instruction or memory construct, a decompiler error results. Usually there's an error number associated with it.
The crucial thing for you to know, Johnny, is what revision of what software package are you trying to use to upload the program from the SLC-5/01 ?
If you search the Rockwell Knowledgebase for the keyword "decompiler" you will find a handful of notes that apply to specific revisions of specific editors. In almost every case, the fix is to get a newer editor or use an older editor to change the condition that causes the decompiler error.
