Please Correct Me If I Am Mistaken

ALL comments are WELCOME - THANKS  in advance! 

I am no expert, but I think if you mix TMCC and Legacy in a lash up, TMCC is the default operating mode. 

You have to run in TMCC mode if you have a TMCC engine in the MU.

You can not run a TMCC engine in Legacy mode, only CAB-1 or TMCC.  In most cases the engine will behave better in TMCC mode.  If the engine already has an id, you can address it from the CAB-2 and then set the mode.  Modes can be toggled for a variety of reasons.  I believe that you are correct in that any engine you call up will default to CAB-1 unless it is a Legacy engine and then it will default to Legacy.

 

Or, you can add the locomotive info manually, see pages 46 & 47 in the legacy system  instruction manual.

 

I agree with Chuck, Lionel TMCC engines run smoothest in TMCC mode.

 

 

I appreciate all the answers but I am still confused about one point:

 

Aren't Cab-1 and TMCC the SAME mode of operation, the only difference being that I am using the Legacy remote? 

Nope, not even close.  Cab-1 was originally designed to run the Powermasters.  It has a number of severe deficiencies that has kept every LCRU orR2LC locomotive ever made from running the way it actually could.  It was the source of most of the problems with the Original Odyssey engines as well.  The CAB-2 finally allows you to run TMCC trains the way they were meant to be run While giving you access to all of the new features in Legacy equipped engines.  Plus, you can run them the old fashioned way (as well as control the devices that need relative speed steps (PowerMasters, TPC's and some accessories (crane car)).

The Legacy system will not automatically set the type. Loading the generic module will set it to TMCC mode which works for Lionel engines. The CAB 1
Mode is for some non standard TMCC equipped engines. It's the fall back when all else fails mode

Look at www.martye.com he has a video on how to set up a TMCC engine with the generic module.

Hi Chuck,
Can you elaborate on the deficiencies of the Cab-1.
Like what are they and how does the Cab-2 overcome them when using TMCC mode.

Also what are the weaknesses or deficiencies of the Cab-2 besides the weak data signal for all the controllers other than the besides the Sc-1 and 2s.

Thanks,
I am still on the fence, but with the current shortage and no Legacy engines, I guess I do not know what I am missing.
Do K-line and TAS run better in TMCC mode also. Or just Cab-1?
No point in upgrading if it does not improve the majority of my stuff. Mostly K-line TMCC

never heard or have I had this issue with weak data signal.

CAB-1 has addressing limitations on TR, 9 instead of 15.  It's biggest problem is with the speed step commands.  TMCC has always had an absolute speed function command with 32 steps.  CAB-1 can only generate +/- "delta" steps.  This is the primary reason that Odyssey one engines had trouble with the cruise function in TMCC.  I had one Odyssey one engine that I would only run with Odyssey turned off because it ran so poorly in Command mode.  When I got the CAB-2 the engine ran like a charm unless I set the mode to CAB-1.  

 

I don't have any K-Line engines and I generally don't like cruise control.  Some of the third part cruise solutions require use of CAB-1 mode to work properly.  You would still have access to other extremely useful CAB-2 features like Train Brake but the speed step function would be no different than a CAB-1.

 

Legacy base does have issues with driving a long chain of IC control style devices that  use the serial data interface.  You have to use a line driver to "boost" the signal.  I only have some TPC's and there aren't enough of them to cause problems.

 

I just got my first Legacy engine back in August.  I got the Legacy base and CAB-2 almost two and a half years ago.  Once I started using the CAB-2 I put the original set away and only use it for test purposes.  All of my engines ran so much better with the new controller/base it didn't make sense to use it.

My CAB1/Command Base is on my workbench for testing, once you run with the CAB2/Legacy, I can't imagine going back.