The difference between MCU assembly pseudo instructions DATA and EQU-EEWORLD

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1. The EQU instruction is used to assign a value or register name to a specified symbol name.

Format: symbol name EQU expression

Symbolic Name EQU Register Name

The expression must be a simple relocation expression.

The character name assigned by the EQU instruction can be used as a data address, code address, bit address or directly as an immediate value.

for example:

s equ bx+si

mov cx, [s]

Then the above two codes are equivalent to the following instructions:

mov cx，[bx+si]

2. The DATA instruction is used to assign an internal RAM address to a specified symbol name.

Format: symbol name DATA expression

The value of the numeric expression is between 0 and 255, and the expression must be a simple relocation expression.

for example:

TEM DATA 50H

tem is an address

DATA (data address assignment command).

Function: Assign data address or code to the specified character name.

Format: WATER DATA 30H.

※Differences between EQU and DATA:

1) EQU must be defined before use, but DATA does not need to be defined.

2) EQU can assign an assembly symbol to a character name, while DATA

Pseudo-instructions cannot.

3) DATA can be used in expressions, but EQU cannot.

Keywords：MCU Reference address：The difference between MCU assembly pseudo instructions DATA and EQU

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