TMS320F280039C: File extensions: What are these file extensions? Are they binary? What is the purpose and use case?

While searching the C:\ti directory for the meaning of ti_catalog_..... that used in the C2000 .cfg file I found the following file extensions. I plugged these extensions into the Texas Instrument search bar but there were no quick concrete results, just mentions in various posts. It would be nice for TI to create glossary or quick lookup for information like this. Then when the user puts in the search bar, it would be elevated to the first result.

Here are the extensions in question:

.sem3

.sm3g

.srm3

.xdt

.aem3

.am3

.am3g

.arm3

.aem4

.am4f

.am4g

,am4fg

.xdc

.xs

Various assembly files. For C2000? Why are they marked 28? Are they restricted to use with C28x devices?

.h28 - Assembly header file

.s28 - Assembly file of some sort

.a28FP - Assembly file? FP is likely the floating point implementation. Why a28 vs. s28?

.a28L - Assembly file? L is likely non-FP Long implementation. What is a28 vs. s28?

.ae28FP - Assembly file? FP is likely the floating point implementation. Why a28 vs. ae28 vs. s28?

See attached file...

SearchTerm_ti_catalog_results.csv