Floating-Point-to-Integer Conversion
FIX
13-99
Assembly Language Instructions
Syntax
FIX
src, dst
Operation
fix
(src)
→
dst
Operands
src general addressing modes (G):
0 0
register (R
n, 0
≤
n
≤
7)
0 1
direct
1 0
indirect (disp = 0–255, IR0, IR1)
1 1
immediate
dst any CPU register
Opcode
31
24 23
16
8 7
0
15
0 0 0 0 0 1
G
dst
src
0 1 0
Description
The floating-point operand
src is rounded down to the nearest integral value
less than or equal to floating-point value, and the result is loaded into the
dst
register. The
src operand is assumed to be a floating-point number and the dst
operand a signed integer.
The exponent field of the
dst register (bits 39–32) is not modified.
Integer overflow occurs when the floating-point number is too large to be repre-
sented as a 32-bit 2s-complement integer. In the case of integer overflow, the
result is saturated in the direction of overflow.
Cycles
1
Status Bits
These condition flags are modified only if the destination register is R7 – R0.
LUF
Unaffected
LV
1 if an integer overflow occurs; unchanged otherwise
UF
0
N
1 if a negative result is generated; 0 otherwise
Z
1 if a 0 result is generated; 0 otherwise
V
1 if an integer overflow occurs; 0 otherwise
C
Unaffected
OVM
Operation is not affected by OVM bit value.
Mode Bit