[lwip-users] Porting with slip on cortex m3

[Hard Maker]

Hi list,
I'm new with lwip. I'm not shure about how can port lwip to use slip on 
cortex m3. I view the contrib package (zip file) but I can't find any 
complete application as reference (main.c, arch/cc.h, etc).
Someone was port the library to cortex m3 and tellme wath can I read to 
do this?
I'm working in a baremetal development (without os).
Very thank's

Sergio