Slide 5.3: Intrinsic data types

Slide 5.2: Defining data
Slide 5.4: Data definition statements
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Intrinsic Data Types

           .data
              value1      WORD      100h
              value2      SDWORD    -40000
              value3      BYTE      'A'
              finalVal    DWORD     ?

MASM defines various intrinsic data types, each of which describes a set of values that can be assigned to variables and expressions of the given type. In the table below, all data types pertain to integers except the last three. The notation “IEEE” refers to standard real number formats published by the IEEE Computer Society.

Type	Usage	Example
`BYTE`	8-bit unsigned integer	`value1 BYTE 'A'`
`SBYTE`	8-bit signed integer	`Value2 SBYTE -128`
`WORD`	16-bit unsigned intger	`_value3 WORD 100h`
`SWORD`	16-bit signed integer	`@value4 SWORD ?`
`DWORD`	32-bit unsigned integer	`$value5 DWORD 1, 2, 3, 4, 5`
`SDWORD`	32-bit signed integer	`_6 SDWORD -20d`
`FWORD`	48-bit integer	`@7 FWORD 0`
`QWORD`	64-bit integer	`$8 QWORD -100q`
`TBYTE`	80-bit (10-byte) integer	`_ TBYTE 05E39h`
`REAL4`	32-bit (4-byte) IEEE short real	`@ REAL4 -1.6`
`REAL8`	64-bit (8-byte) IEEE long real	`$@ REAL8 1.2E-12`
`REAL10`	80-bit (10-byte) IEEE extended real	`@_$ REAL 3.2E+1024`