gettime is actually a TI-basic command, and it has no equivalent in axe. However, if it's absolutely necessary, it would theoretically be possible to run a basic program from within axe, get and store the time, and then import it from within the axe program again.

yes, it is possible ...   

against, it will be necessary prevent that this program is only available for ti 84 + (the 83 + did not do this to my knowledge  :'().

You need to remember that Axe is not Basic. It only uses the same tokens.

Exactly that. Axe is a completely separate language that just uses the BASIC tokens to keep things simple, so you can't assume a command works in Axe just because you can use it in TI-BASIC.

The Commands.htm file contains exactly every command you can use in Axe, no more and no less.