Datasheet

Chapter 3. Hardware Multiply/Accumulate (MAC) Unit 3-5
MAC Instruction Execution Timings
• Two’s complement unsigned integer: In this format, an N-bit operand represents a
number within the range 0 <
operand < 2
N
- 1. The binary point is to the right of the
least significant bit.
• Two’s complement, signed fractional: In an N-bit number, the first bit is the sign bit.
The remaining bits signify the first N-1 bits after the binary point. Given an N-bit
number, a
N-1
a
N-2
a
N-3
... a
2
a
1
a
0
, its value is given by the following formula:
This format can represent numbers in the range -1 <
operand < 1 - 2
(N-1)
.
For words and longwords, the greatest negative number that can be represented is -1,
whose internal representation is 0x8000 and 0x0x8000_0000, respectively. The
most positive word is 0x7FFF or (1 - 2
-15
); the most positive longword is
0x7FFF_FFFF or (1 - 2
-31
).
3.2 MAC Instruction Execution Timings
Table 3-2 shows standard timings for two-operand MAC instructions.
Table 3-3 shows standard timings for MAC move instructions.
Table 3-2. Two-Operand MAC Instruction Execution Times
Opcode <ea>
Effective Address
Rn (An) (An)+ -(An) (d16,An) (d8,An,Xi*SF) (xxx).wl #<xxx>
mac.w Ry,Rx 1(0/0) — — — — — — —
mac.l Ry,Rx 3(0/0) — — — — — — —
msac.w Ry,Rx 1(0/0) — — — — — — —
msac.l Ry,Rx 3(0/0) — — — — — — —
mac.w Ry,Rx,ea,Rw — 1(1/0) 1(1/0) 1(1/0) 1(1/0) — — —
mac.l Ry,Rx,ea,Rw — 3(1/0) 3(1/0) 3(1/0) 3(1/0) — — —
msac.w Ry,Rx,ea,Rw — 1(1/0) 1(1/0) 1(1/0) 1(1/0) — — —
msac.l Ry,Rx,ea,Rw — 3(1/0) 3(1/0) 3(1/0) 3(1/0) — — —
muls.w <ea>,Dx 3(0/0) 3(1/0) 3(1/0) 3(1/0) 3(1/0) 4(1/0) 3(1/0) 3(0/0)
mulu.w <ea>,Dx 3(0/0) 3(1/0) 3(1/0) 3(1/0) 3(1/0) 4(1/0) 3(1/0) 3(0/0)
muls.l <ea>,Dx 5(0/0) 5(1/0) 5(1/0) 5(1/0) 5(1/0) — — —
mulu.l <ea>,Dx 5(0/0) 5(1/0) 5(1/0) 5(1/0) 5(1/0) — — —
2
i1N–+()
ai⋅
i0=
N2–
∑
+