Yea, in lathe you might have better format with: T*** H*** M6
With the M6 you can write to one of your unused axis(s), to operate your turret ATC, or, you can write out to a PLC.
I use a PLC on both My mill and lathe, The good thing about a plc is you can run independant motion modules in it, that
can operate outside of Mach, thus your ATC can do things while Mach is Machining............
It IS more expensive to go with a PLC but the benefits, IF, your doing this for money is well worth it. If this is just occasional hobbie
(Unless your finacially independant), it is easier to set up one of machs unused axis.
Just to give you an idea I use a ADC DL06 that has 2 motion modules (High speed counters), and on 4-2Analog module, One extra I/O card, I use the 2 motion
for a "read a head" swap arm type ATC on the mill, and a Slit tail ATC on my Lathe, (the turret handles the profile tools, the tail handels the boring/drilling).
You can really fancey if you want and make a Y-axis lathe with a secondary Drop Spindle for the other side with swap spindle mcodes and relays.
Again though requiring a PLC for the above. cost of that plc system: about $600.00 plus the programing software about 500.00 (it has a line limited free version), Plus programming cables,
and the time you spend writing you Ladder, personally I prefer Stage programming it is much better for more complex stuff.
The format of: Txx Hxx M6 works both in Mill and Lathe...........
Scott