ADDRESSING4 - 26 ADDRESS GENERATION UNIT MOTOROLA
LINEAR ADDRESS MODIFIER
M0 = 255 = 11111111 FOR LINEAR ADDRESSING WITH R0
ORIGINAL REGISTERS: N0 = 5, R0 = 75 = 0100 1011
POSTINCREMENT BY OFFSET N0: R0 = 80 = 0101 0000
POSTINCREMENT BY OFFSET N0: R0 = 85 = 0101 0101
POSTINCREMENT BY OFFSET N0: R0 = 90 = 0101 1010
MODULO ADDRESS MODIFIER
M0 = 19 = 0001 0011 FOR MODULO 20 ADDRESSING WITH R0
ORIGINAL REGISTERS: N0 = 5, R0 = 75 = 0100 1011
POSTINCREMENT BY OFFSET N0: R0 = 80 = 0101 0000
POSTINCREMENT BY OFFSET N0: R0 = 65 = 0100 0001
POSTINCREMENT BY OFFSET N0: R0 = 70 = 0100 0110
REVERSE-CARRY ADDRESS MODIFIER
M0 = 0= 0000 0000 FOR REVERSE-CARRY ADDRESSING WITH R0
ORIGINAL REGISTERS: N0 = 8, R0 = 64 = 0100 0000
POSTINCREMENT BY OFFSET N0: R0 = 72 = 0100 1000
POSTINCREMENT BY OFFSET N0: R0 = 68 = 0100 0100
POSTINCREMENT BY OFFSET N0: R0 = 76 = 0100 1100
75
80
85
90
R0
65
70
75
80
R0
64
83
UPPER
BOUNDARY
LOWER
BOUNDARY
64
68
72
76
R0
Figure 4-15 Address Modifier Summary