Motors not working

Hi everyone,

I'm asking for help. I can't drive any stepper motors on my reprap :(

I built my reprap Huxley from reprappro two years ago, and it was working well. Since THE day.
I don't now why, I was trying the heabed regulation was defective... I think that a surintensity destroyed my atmega, the it was impossible de communicate with it.
So I bought a new sanguinololu 1.3a assembled and tested to provide any problem. But without stepper drivers (I thougt there was only a problem with atmega or ftdi).

My config is:
-Reprap Huxley
-Sanguinololu 1.3a
-Marlin 1.0.1
-Pronterface/Skinforge

When I recieved sanguinololu I loaded marlin firmware, I only check these 3 lines before:
#define REPRAPPRO_HUXLEY
#define REPRAPPRO_SANGUINOLOLU
#define SERIAL_R 4700

Now when I launch pronterface, it's blocked on "connecting..." (com port and baudrate are ok), and I don't hear the motors initialisation like before...
If I click on "reset printer", all functionnalities are functionnals(...) (heatbed, extruder heat, captors...), exept motors.

I don't know what ti do then...

I tried the montage below, to check each stepper motors an driver whith an arduino mega (almost copied from Jose Perez de Lama.

With the code found here..
But none or motors or drivers works...

Is it possible that I broke all the 4 stepper motors in one time ?

What can I do ?

Fuji