#pragma udata specific_loc_var=0x100
char user_c1,user_c2;
int user_i1,user_i2;
This will start allocating variables from ram location 0x100,
2 single-byte variables (user_c1 and user_c2)
then 2 double-byte variables (user_i1 and user_i2)
All those are in consecutive manner. (ie start in 0x100 end at 0x106)