7 fpu instruction execution times, Fpu instruction execution times -35 – Freescale Semiconductor MCF5480 User Manual
Page 139

Instruction Execution Timing
MCF548x Reference Manual, Rev. 3
Freescale Semiconductor
3-35
Execution times for moving the contents of the ACC, ACCext[01,23], MACSR, or MASK into a
destination location <ea>x in this table represent the best-case scenario when the store is executed and no
load, copy, MAC, or MSAC instructions are in the EMAC execution pipeline. In general, these store
operations require only a single cycle for execution, but if preceded immediately by a load, copy, MAC,
or MSAC instruction, the depth of the EMAC pipeline is exposed and the execution time is 4 cycles.
3.7.7
FPU Instruction Execution Times
specifies the instruction execution times associated with the FPU execute engine.
mulu.l
<ea>y,Dx
4(0/0)
4(1/0)
4(1/0)
4(1/0)
4(1/0)
—
—
—
mulu.w
<ea>y,Dx
4(0/0)
4(1/0)
4(1/0)
4(1/0)
4(1/0)
5(1/0)
4(1/0)
4(0/0)
1
Effective address of (d16,PC) not supported.
2
Storing the accumulator requires 1 additional clock cycle when saturation is enabled, or fractional rounding is performed
(MACSR[7:4] = 1---, -11-, --11).
Table 3-20. FPU Instruction Execution Times
1,
2
Opcode
Format
Effective Address <ea>
FPn
Dn
(An)
(An)+
–(An)
(d
16
,An)
(d
16
,PC)
fabs
<ea>y,FPx
1(0/0)
1(0/0)
1(1/0)
1(1/0)
1(1/0)
1(1/0)
1(1/0)
fadd
<ea>y,FPx
4(0/0)
4(0/0)
4(1/0)
4(1/0)
4(1/0)
4(1/0)
4(1/0)
fbcc
<label>
—
—
—
—
—
—
2(0/0) if correct,
9(0/0) if incorrect
fcmp
<ea>y,FPx
4(0/0)
4(0/0)
4(1/0)
4(1/0)
4(1/0)
4(1/0)
4(1/0)
fdiv
<ea>y,FPx
23(0/0)
23(0/0)
23(1/0)
23(1/0)
23(1/0)
23(1/0)
23(1/0)
fint
<ea>y,FPx
4(0/0)
4(0/0)
4(1/0)
4(1/0)
4(1/0)
4(1/0)
4(1/0)
fintrz
<ea>y,FPx
4(0/0)
4(0/0)
4(1/0)
4(1/0)
4(1/0)
4(1/0)
4(1/0)
fmove
<ea>y,FPx
1(0/0)
1(0/0)
1(1/0)
1(1/0)
1(1/0)
1(1/0)
1(1/0)
fmove
FPy,<ea>x
—
2(0/1)
2(0/1)
2(0/1)
2(0/1)
2(0/1)
—
fmove
<ea>y,FP*R
—
6(0/0)
6(1/0)
6(1/0)
6(1/0)
6(1/0)
6(1/0)
fmove
FP*R,<ea>x
—
1(0/0)
1(0/1)
1(0/1)
1(0/1)
1(0/1)
—
fmovem
3
<ea>y,#list
—
—
2n(2n/0)
—
—
2n(2n/0)
2n(2n/0)
fmovem
3,
4
#list,<ea>x
—
—
1+2n(0/2n)
—
—
1+2n(0/2n)
—
fmul
<ea>y,FPx
4(0/0)
4(0/0)
4(1/0)
4(1/0)
4(1/0)
4(1/0)
4(1/0)
fneg
<ea>y,FPx
1(0/0)
1(0/0)
1(1/0)
1(1/0)
1(1/0)
1(1/0)
1(1/0)
fnop
—
—
—
—
—
—
2(0/0)
frestore
<ea>y
—
—
6(4/0)
—
—
6(4/0)
6(4/0)
Table 3-19. EMAC Instruction Execution Times
Opcode
<ea>y
Effective Address
Rn
(An)
(An)+
–(An)
(d16,An)
(d16,PC)
(d8,An,Xi*SF)
(d8,PC,Xi*SF)
xxx.wl
#xxx