Delay Slots

 

 

 

 

 

Table 3−8. Delay Slot and Functional Unit Latency

 

 

 

 

 

 

 

 

 

 

Delay

Functional

 

Write

 

Instruction Type

Slots

Unit Latency

Read Cycles

Cycles

 

Single cycle

0

1

i

i

 

2-cycle DP

1

1

i

i, i + 1

 

DP compare

1

2

i, i + 1

1 + 1

 

4-cycle

3

1

i

i + 3

 

INTDP

4

1

i

i + 3, i + 4

 

Load

4

1

i

i, i + 4

 

MPYSP2DP

4

2

i

i + 3, i + 4

 

ADDDP/SUBDP

6

2

i, i + 1

i + 5, i + 6

 

MPYSPDP

6

3

i, i + 1

i + 5, i + 6

 

MPYI

8

4

i, i + 1, 1 + 2, i + 3

i + 8

 

MPYID

9

4

i, i + 1, 1 + 2, i + 3

i + 8, i + 9

 

MPYDP

9

4

i, i + 1, 1 + 2, i + 3

i + 8, i + 9

 

Cycle i is in the E1 pipeline phase.

A write on cycle i + 4 uses a separate write port from other .D unit instructions.

SPRU733

Instruction Set

3-15

Page 75
Image 75
Texas Instruments TMS320C67X/C67X+ DSP manual 8. Delay Slot and Functional Unit Latency