FLD             Load real                            Exceptions: I D
C3 C2 C1 C0: ? ? * ?
FLD source

Logic push source into ST

FLD pushes source onto the FPU stack and is the basic instruction
for moving data into the FPU.
If the source is a register, the register number used is that before
the stack-top pointer is decremented. If source is in single or
double FP format, it is automatically converted to extended real
format.

Example
fld [mem64] ; load double
fld ST(0) ; duplicate stack top


Note
ST(7) must be empty; otherwise, the CPU receives an invalid
operation exception.


Opcode Format
D9 /0 FLD m32
DD /0 FLD m64
DB /5 FLD m80
D9 C0 + i FLD ST(i)


Timing
Operand 8087 287 387 486 Pentium
reg 17-22 17-22 14 4 1 FX
m32 (38-56)+EA 38-56 20 3 1 FX
m64 (40-60)+EA 40-60 25 3 1 FX
m80 (53-65)+EA 53-65 44 6 3 NP