Development Tools

.db4/.dw

Initialization of 4-byte area.

[Syntax]

Symbol field	Mnemonic field	Operand field	Comment field
[label:]	.db4	expression[, ... ]	[; comment]
[label:]	.dw	expression[, ... ]	[; comment]

[Function]

-	The .db4 and .dw directive tells the assembler to initialize a memory area in 4-byte units with the initial value(s) specified in the operand field.

[Use]

-	Use the .db4 and .dw directive when defining a 4-byte numeric constant such as an address or data used in the program.

[Description]

-	The assembler initializes 4-byte area with:

(a)	Expression

The value of an expression must be 4-byte data. Therefore, the value of the operand must be in the range of 0x0 to 0xFFFFFFFF. If the value exceeds 4-byte, the assembler will use only lower 2-byte of the value as valid data.

No character string constants can be described as an initial value.

-	Two or more initial values may be specified within a statement line of the .db4 and .dw directive.

-	As an initial value, an expression that includes a relocatable symbol or external reference symbol may be described.

-	If the relocation attribute of the section containing the .db4 and .dw directive is "BSS", then an error is output because initial values cannot be specified.