ZiLOG eZ80 User Manual

eZ80
®
CPU
User Manual
UM007714-0908 Addressing Modes
50
Indexed Addressing
In this mode of addressing, a byte of data following the opcode contains a displacement to
be added to one of the IX or IY Index registers. The displacement is a two’s-complement
value in the range +127 to –128. Figure 8 displays the indexed addressing.
Extended Addressing
The memory operand address is specified by two or three bytes following the opcode. Fig-
ure 9 displays the extended addressing.
Relative Addressing
Relative addressing uses one byte of data following the opcode to specify a displacement
from the existing program to which a program jump can occur. The displacement is a
two’s-complement number that is added to the address of the opcode following the
Figure 8. Indexed Addressing
Figure 9. Extended Addressing
Operand
Op Code 2
Displacement (d)
Op Code 1
Index Register (IX or IY)
Memory Space
+
Operand
mm
MM
nn
Op Code
{MM, mm, nn}
Memory Space

ZiLOG eZ80 Specifications

General

Brand	ZiLOG
Model	eZ80
Category	Computer Hardware
Language	English