There was never a Turbo Pascal Version for the Atari ST. But you could run a MSDOS-Emulator and then use the DOS version of TP.
You miss my point. DR OSes, including CP/M-68K, didn't know about directories and that presumably affects the earliest versions of TOS. Software of that era including Turbo Pascal used fixed-length 8.3 filenames in FCBs and had no API for either changing directory or specifying that a file was in a particular directory.
Pascal for Atari ST :
* UCSD Pascal, ported to Motorola 68000 by Focus, Hannover
* ST Pascal from CCD (with the utils function EatSpaces )
Plus Hisoft HighSpeed Pascal.
Beware of using 8th bit for filenames: Beyond #127 Atari had its own idea where to put äüö and the others.
Also some DR OSes and derivatives used the MSB of the 8.3 filename in the FCB to indicate special file access attributes. That's probably later than the TOS fork.
So I think what I'm really trying to say is that there are plentiful gotchas that can inflict any attempt to get something like FPC ported to an OS of that era... unless it really has been augmented with a unix-like (or at least MS-DOS v3 like) API. And I've done enough support etc. work to know just how difficult the OS imitation game can be.
MarkMLl