uClinux detects less RAM memory than I have

Hi all,

Can anyone explain me why uClinux detects less RAM memory than I have? I have a 16 MBytes SDRAM, but uClinux can see just 12,2 MBytes. I apologize if this is a stupid question.

I already tried to force "mem=16M" in <Processor type and features> --> <Default kernel command string>, but with no results.

Thanks in advance

Marco