Address Indirect Addressing Mode ([EXT3])

This addressing mode uses a 24-bit constant to point to a pointer which is then used to access the operand. This allows a 24-bit pointer to an operand to be located anywhere in the 16-megabyte memory space. The 24-bit constant address that points to the pointer to the operand is supplied as three extension bytes in the object code of the instruction.

Listing: Example - Address Indirect Addressing Mode

ORG $1100
Cnst_tbl DC.W $10,$11,$12,$13

ORG $1114

ptr DS 3

ORG $FF0000

main:

      MOV.P     #Cnst_tbl,$1114

      LD        D2,[$1114]

      CMP       D2,#10

Ptr points to address of Cnst_tbl. Then the first value of Cnst_tbl array is loaded to D2 and compared with value 10.