Zilog Z8F0130 - Manual (Page 51)

eZ8
™
CPU Core
User Manual
UM012820-0810 Addressing Modes
29
Register Addressing Using 8-Bit Addresses
Registers or Register Pairs may be accessed using 8-bit addresses sup-
plied in the operands. Any of the 256 registers on the current Register File
Page can be accessed using 8-bit addressing. The upper 4-bits of the

12-bit address is provided by the Page Pointer, RP[3:0] . The full 12-bit
address is provided by {RP[3:0], Address[7:0]} .
Figure 9 displays using 8-bit addressing, the destination and/or source
address specified corresponds to a register in the Register File.
Register Addressing Using 4-Bit Addresses
Working Registers or Working Register Pairs can be accessed using 4-bit
addresses supplied in the operands. With 4-bit Addressing, the destination
and/or source addresses point to one of the 16 possible Working Registers
Figure 9. Register Addressing Using 8-Bit Addresses
One 8-bit
Program Memory
Address
(dst)
One Operand
Instruction
(Example)
Op Code
dst[7:0]
Destination
Register File
Register
12-bit address is
{RP[3:0], dst[7:0]}