Bit Operands; Byte Operands; Short-Integer Operands - Intel 8XC196NT User Manual

8XC196NT USER'S MANUAL
Table 3-2 lists the equivalent operand-type names for both C programming and assembly lan-
guage.
Table 3-2. Equivalent Operand Types for Assembly and C Programming Languages
Operand Types Assembly Language Equivalent
BYTE BYTE
SHORT-INTEGER BYTE
WORD WORD
INTEGER WORD
DOUBLE-WORD LONG
LONG-INTEGER LONG
QUAD WORD —
3.1.1

BIT Operands

A BIT is a single-bit variable that can have the Boolean values, "true" and "false." The architec-
ture requires that BITs be addressed as components of BYTEs or WORDs. It does not support the
direct addressing of BITs.
3.1.2

BYTE Operands

A BYTE is an unsigned, 8-bit variable that can take on values from 0 through 255 (2
metic and relational operators can be applied to BYTE operands, but the result must be interpret-
ed in modulo 256 arithmetic. Logical operations on BYTEs are applied bitwise. Bits within
BYTEs are labeled from 0 to 7; bit 0 is the least-significant bit. There are no alignment restric-
tions for BYTEs, so they may be placed anywhere in the address space.
3.1.3

SHORT-INTEGER Operands

A SHORT-INTEGER is an 8-bit, signed variable that can take on values from –128 (–2
7
+127 (+2 –1). Arithmetic operations that generate results outside the range of a SHORT-
INTEGER set the overflow flags in the processor status word (PSW). The numeric result is the
same as the result of the equivalent operation on BYTE variables. There are no alignment restric-
tions on SHORT-INTEGERs, so they may be placed anywhere in the address space.
3-2
C Programming Language Equivalent
unsigned char
char
unsigned int
int
unsigned long
long
—
8
–1). Arith-
7
) through