I have heard that some ARM processors can switch between little or big endian in boot time, so which is the activated mode in 2501B? Any ideas or any experience?
[size=75]P.S. I am a fan of little endian architecture because when you use big endian and make a typecast (in assembler), you must change the pointer in memory.[/size]
You have heard correctly!
That is a very good question, and something which obviously should be clearly documented, shouldn’t it?
Unfortunately, this is Wavecom - and it isn’t. 
My guess is that Open-AT is Little-Endian - see:
wavecom.com/modules/movie/sc … .php?t=519
But, again, this is basic information that needs to be clearly documented - we should not have to guess!