Freescale Semiconductor SC140 specifications Rule L.D.3, Rule L.D.5, Rule L.D.6

Models: SC140

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Static Programming Rules

Rule L.D.3

The minimum number of VLES between the following instructions that write a LCn register and SA of the same short loop n is:

DOENSHn Rn or #x: one VLES (address register or immediate value)

DOENSHn Dn: two VLES (data register)

MOVE-like instruction that writes a LCn register: two VLES

Example 7-60. LCn Write at the Start of Short Loop n

move.w

#3,r0

;allowed

doensh0

r0

move.l

d1,lc0

;not allowed

move.w

#2,d2

 

loopstart0 inc d1 loopend0

Rule L.D.5

The minimum number of VLES between an instruction that writes any LCn register and a CONT/CONTD instruction is:

Any DOENn Rn or #x : one VLES (address register or immediate value)

Any DOENn Dn: two VLES (data register)

MOVE-like instruction that writes any LCn register: two VLES

Example 7-61. LCn Write to CONT/D Instruction

doen1 #5

 

...

 

loopstart1

 

loop1 nop

 

move.l d0,lc1

 

nop

;not allowed

cont label

nop

 

nop

 

loopend1

 

Rule L.D.6

AMOVE-like instruction that writes a SAn register is not allowed at (LA-3), (LA-2), (LA-1), and LA of the same long loop n.

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SC140 DSP Core Reference Manual

Page 284
Image 284
Freescale Semiconductor SC140 Rule L.D.3, Rule L.D.5, Rule L.D.6, Example 7-60. LCn Write at the Start of Short Loop n