Zilog Z8F0130 - Manual (Page 50)

eZ8
™
CPU Core
User Manual
UM012820-0810 Addressing Modes
28
Register Addressing
Extended register addressing, symbol R, is used to directly access any
register in the Register File using either a 12-bit, 8-bit, or 4-bit addressing
methodology.
Register Addressing Using 12-Bit Addresses
The 12-bit address is supplied in the operands. There are two types of
extended mode instructions: Register to Register operations and
Immediate to Register operations.
Figure 8 displays Register addressing
using 12-bit addresses.
Figure 8. Register Addressing Using 12-Bit Addresses
Two 12-bit
Program Memory
Addresses
(dst, src)
Three Operand
Instruction
(Example) Op Code
src[11:4]
{src[3:0},
dst[11:8]}
dst[7:0]
Source
Destination
Register File
Register
Register
12-bit address is
dst[11:0]
12-bit address is
src[11:0]