Power up on BC66 and BC660K-GL

When the BC66 powers up or is reset it sends a message “Leaving the BROM” . The BC660K does not send the same message. I see its sends RDY on reset, but nothing on a power up. Does it send anything on power up? Is there a way using at commands to see why the modem powered up?

if you power on the BC660K,it return
it indicates the module aleady boot completely