S12 XGATE Debugging

[EmbeddedCoder]

Hi all,

I am trying to choose a processor for my next project. My previouse project used a S12 device, and worked very well, the only problem I had towards the end was a bit of a squeeze on RAM resources. A good code trim seemed to sort it out!!

So I am thinking of going towards an S12XE device for my new project - they seem cheaper (I guess Freescale want to puch their new devices) and I am thinking that some of my driver code could be re-used, or at least retain the same style. As a bonus, I can also re-use the Metrowerks license I have!!

Debugging on the particular S12 device we chose previously was quite bad - the silicon had a bug that meant the trace facility in Metrowerks would not function, and only 2 breakpoints - felt like the 1980's...

So, my question is - is the debugging on the S12X devices any better?

Especially with the trace support - is this a useful feature - I'm thinking that with the additional XGATE accelaration there's a good chance the Trace module can get confused, or that debugging without Trace is a nightmare?

Any experiences, general gut feelings, recommendations gratefully received.

Thanks,

Mike

[DPB]

Hello Mike

The on chip debug support for the S12X devices is enhanced with respect to the S12 devices.
The S12X DBG module offers 4 comparator channels with associated breakpoints that can be mapped to either CPU or XGATE and provide for breakpoints on PC addresses or data accesses.

Triggers for tracing use a state sequencer for more flexible control of trace begin or trace end.

Tracing of CPU and/or XGATE is supported by the DBG module. This does not confuse the DBG, but it can be slightly confusing trying to interpret the contents without a suitable debugging tool. For this reason it is recommended to use a debugger such as Codewarrior V4.6 or later. Codewarrior compiles a listing of the code flow from the trace buffer contents automatically.

The BDM and DBG modules are described in detail in chapters 7 & 8 of the S12XE- reference manual...
http://www.freescale.com/files/microcontrollers/doc/data_sheet/MC9S12XEP100RMV1.pdf?fpsp=1

DPB