Texas Instruments TMS320C67X/C67X+ DSP manual 31. MPYSP2DP .M-Unit Instruction Constraints

Models: TMS320C67X/C67X+ DSP

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Functional Unit Constraints

Table 4−31 shows the instruction constraints for MPYSP2DP instructions executing on the .M unit.

Table 4−31. MPYSP2DP .M-Unit Instruction Constraints

 

 

 

 

Instruction Execution

Cycle

1

2

3

4

5

MPYSP2DP

R

R

 

W

W

 

 

 

Instruction Type

 

Subsequent Same-Unit Instruction Executable

16 16 multiply

 

n

Xw

Xw

n

 

MPYDP

 

Xu

n

n

n

MPYI

 

Xu

n

n

n

 

MPYID

 

Xu

n

n

n

MPYSP

 

Xw

n

n

n

MPYSPDP

 

Xu

n

n

n

MPYSP2DP

 

Xw

n

n

n

 

 

 

Instruction Type

Same Side, Different Unit, Both Using Cross Path Executable

 

 

 

 

 

 

Single-cycle

 

Xr

n

n

n

Load

 

Xr

n

n

n

Store

 

Xr

n

n

n

DP compare

 

Xr

n

n

n

2-cycle DP

 

Xr

n

n

n

Branch

 

Xr

n

n

n

4-cycle

 

Xr

n

n

n

INTDP

 

Xr

n

n

n

ADDDP/SUBDP

 

Xr

n

n

n

 

 

 

 

 

 

Legend: = E1 phase of the single-cycle instruction; R = Sources read for the instruction; W = Destinations written for the instruction; n = Next instruction can enter E1 during cycle; Xr = Next instruction cannot enter E1 during cycle−read/ decode constraint; Xw = Next instruction cannot enter E1 during cycle−write constraint; Xu = Next instruction cannot enter E1 during cycle−other resource conflict

SPRU733

Pipeline

4-47

Page 379
Image 379
Texas Instruments TMS320C67X/C67X+ DSP manual 31. MPYSP2DP .M-Unit Instruction Constraints