in general terms are ARM peripherals similar across vendors ?

Our small tech group use multiple ARM MCUs - several vendors.  (your "A" vendor being one)

Now if ARM provided full peripheral implementation - how would each vendor apply their particular, "black magic?"  If that proved the case - "similarity" you mention would be maximized - would it not?

I can report that we've found a dramatic increase in PWM capability & performance when moving from Cortex M3 to Cortex M4.  Far more registers enable much more control - yet that added capability comes at the price of added complexity.

Beyond the hardware - each (well most) vendors' supply some form of API - suspect that is where your major concern will lie.

It's hard to imagine that one vendor will consistently offer best price, performance, features, api, and availability.  Thus our election of vendor-agnostic IDE - and our hunt for vendors offering the full Cortex spectrum: M0, M3, & M4.

Suspect your question is best answered by "side by side" comparison of each critical peripheral.  Most all vendors provide low-cost eval boards which speed, ease & enhance your investigation...

Hello Ralph,

cb1's point duly noted: The peripheral design of TM4C devices are specific to us. Any resemblance or register name/function similarity with outside vendors would be co-incidental.

As cb1 also mentioned, the software structure would be the major concern for migration, as the programming sequence of TM4C peripherals are specific to TM4C devices (may not find the same with other TI MCU offerings)

Regards

Amit

Suppose your summary is broadly correct - but more normal/customary "Verify" would be awarded to post(s) which dealt with your technical detail - which the "self-awarded" Verify did not...