4 absolute mode – Texas Instruments MSP430x4xx User Manual

Page 47

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Addressing Modes

3-13

RISC 16-Bit CPU

3.3.4

Absolute Mode

The absolute mode is described in Table 3−7.

Table 3−7. Absolute Mode Description

Assembler Code

Content of ROM

MOV &EDE,&TONI

MOV X(0),Y(0)

X = EDE

Y = TONI

Length:

Two or three words

Operation:

Move the contents of the source address EDE to the
destination address TONI. The words after the instruction
contain the absolute address of the source and destination
addresses. With absolute mode, the PC is incremented
automatically so that program execution continues with the
next instruction.

Comment:

Valid for source and destination

Example:

MOV &EDE,&TONI ;Source address EDE=0F016h,

;dest. address TONI=01114h

01114h

Address
Space

0F016h

04292h

PC

0FF16h

0FF14h

0FF12h

0xxxxh

0A123h

0F018h

0F016h

0F014h

0xxxxh

0xxxxh

01234h

01116h

01114h

01112h

0xxxxh

Register

Before:

01114h

Address
Space

0F016h

04292h

PC

0FF16h

0FF14h

0FF12h

0xxxxh

0A123h

0F018h

0F016h

0F014h

0xxxxh

0xxxxh

0A123h

01116h

01114h

01112h

0xxxxh

Register

After:

0xxxxh

This address mode is mainly for hardware peripheral modules that are located
at an absolute, fixed address. These are addressed with absolute mode to
ensure software transportability (for example, position-independent code).

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