I'm feeling generous today!

mov a,#67
call hex2bin
loop:
sjmp loop

; value to convert in A
; uses A,R2,R3
hex2bin:
mov r3,a ;save value in R3
mov R2,#8 ;8 bits to convert

h1_loop:
mov a,r3
rlc a ;get bit into carry
mov r3,a
jc one

mov a,#'0' ;if a '0' bit
sjmp h2

one:
mov a,#'1' ;if a '1' bit

h2:
call plcd ;char in A to lcd

djnz r2,h1_loop ;do for the 8 bits
ret

This should print 8 bits of 1's and 0's depending on the input value. Is this what you wanted?
This code was concocted off the top of my head so there may be errors, but the basic concept is there.