Hello,

I will show you how it work :
(I put table after subroutine LookUp!)

ACCESS_INDEX equ 864
ACCESS_COUNT equ 864

main:

MOV R6, #HIGH(ACCESS_INDEX) ;R6=03 (hex)
MOV R7, #LOW(ACCESS_INDEX) ;R7=60 (hex)
;
; Subruotine
LOOKUP3:
mov a, #low(table) ; A=8B (hex)
add a, r7 ; A=EB (hex)
mov dpl, a ; DPTR=00EB
mov a, #high(table) ; A=03
addc a, r6 ; A=03
mov dph, a ; DPTR=03EB
clr a ; A=00
movc A, @A+DPTR ; A=00 (hex)??? A(should)= 4B
RET
table:
DB #04Bh

Where is the error???