ARM WFI Instruction

Jrvanho

Intellectual 730 points

Other Parts Discussed in Thread: OMAPL138

I am writing a simple C application for the ARM side of the OMAPL138 in CCS4.

When I compile asm(" WFI"); or asm(" wfi");

I get the following error:

[E0002] Instruction only available in V7 WFI

Can someone please help me?

Cheers!

over 14 years ago

0 Jrvanho over 14 years ago

Intellectual 730 points

It looks like the this version of the ARM does not support WIF, so I am trying to call the following from a C file:

asm(" MOV R0, #0");
asm(" MCR p15, 0, r0, c7, c0, 4");

But I get the following error:

[E0004]
Coprocessor information field must be an absolute constant
MCR p15, 0, r0, c7, c0, 4

Any help would be greatly appreciated.

Cheers!

0 Loc Truong over 14 years ago in reply to Jrvanho

TI__Intellectual 2620 points

Immediate value needs a #in front of it. the MCR line should be

MCR p15, #0, r0, c7, c0, #4

For more info on asm syntax please look up SPNU118 (ARM Assembly Language Tools V4.7 User's Guide)

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0 Jrvanho over 14 years ago in reply to Loc Truong

Intellectual 730 points

Cheers!

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ARM WFI Instruction