Since portpins rarely move(constants) you could use the LOOKUP statement to get the offset values. Should free up some RAM. The LOOKUP could ofcourse be placed in a subroutine if you need to access it from many different locations in your program. That way saving ROM.
Code:
x      var byte
i       var byte

main:
for i = 0 to 3
'               a  b  c  d
'               0  6  4  2
     LOOKUP i, [0,14,20,26], x
     porta.0[x]=1
     PAUSE 1000
     porta.0[x]=0
     PAUSE 300
next i
/Ingvar