MC80F0804D View Datasheet(PDF) - Unspecified

Part Name

Description

Manufacturer

MC80F0804D

8-BIT SINGLE-CHIP MICROCONTROLLERS

Unspecified 

MC80F0704/0708/0804/0808

8.4 Addressing Mode

The MC8 series MCU uses six addressing modes;

• Register addressing

• Immediate addressing

• Direct page addressing

• Absolute addressing

• Indexed addressing

• Register-indirect addressing

Register Addressing

Register addressing accesses the A, X, Y, C and PSW.

Immediate Addressing → #imm

In this mode, second byte (operand) is accessed as a data imme-

diately.

Example:

0435

ADC #35H

MEMORY

04

A+35H+C → A

35

When G-flag is 1, then RAM address is defined by 16-bit address

which is composed of 8-bit RAM paging register (RPR) and 8-bit

immediate data.

Example: G=1

E45535 LDM 35H,#55H

0135H

data

þ ~~

0F100H

E4

0F101H

55

0F102H

35

data ← 55H

~~

À

Direct Page Addressing → dp

In this mode, a address is specified within direct page.

Example; G=0

C535

LDA 35H

;A ←RAM[35H]

35H

data

~~

0E550H

C5

0E551H

35

À

~~ þ data → A

Absolute Addressing → !abs

Absolute addressing sets corresponding memory data to Data, i.e.

second byte (Operand I) of command becomes lower level ad-

dress and third byte (Operand II) becomes upper level address.

With 3 bytes command, it is possible to access to whole memory

area.

ADC, AND, CMP, CMPX, CMPY, EOR, LDA, LDX, LDY, OR,

SBC, STA, STX, STY

Example;

0735F0 ADC !0F035H

;A ←ROM[0F035H]

0F035H

data

~~

0F100H

07

0F101H

35

0F102H

F0

À

~~ þ A+data+C → A

address: 0F035

The operation within data memory (RAM)

ASL, BIT, DEC, INC, LSR, ROL, ROR

Example; Addressing accesses the address 0135H regardless of

G-flag.

34

October 31, 2011 Ver 1.03

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