ZiLOG eZ8, User Manual

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UM012811-0904 Addressing Modes
eZ8 CPU
User Manual
26
Figure 13. Indexed Register Addressing
DIRECT ADDRESSING (DA)
Figure 14 depicts the Direct Addressing mode.This instruction specifies the address of the
next instruction to be executed. Only the Jump (JP and JP cc) and Call (CALL) instruc-
tions use Direct Addressing. The 16-bit Direct Address is written to the Program Counter.
Two 4-bit
Program Memory
Address
(dst, src)
Two Operand
Instruction
(Example)
Opcode
{dst[3:0],
Destination
Register File
Register
12-bit address is
{RP[3:0], RP[7:4], dst[3:0]}
Value used
in execution
8-
bi
t va
lu
e
w
ri
tt
e
n
to
De
si
tn
a
ti
o
n
Re
gi
st
er
src[3:0]}
Index
+
Source
Register
Source
Value
12-bit address is
{RP[3:0], Source Value + Index}