Lpc1769 _wfi

[lpcware]

Content originally posted in LPCWare by furkan.yuksel on Wed Jul 13 23:31:44 MST 2011
Hi, I'm using LPC17xx and I want to use WFI function. However, when I use it I face with warning "implicit decleration of _WFI". I checked my "core_cm3.c" file and it does not have anything about WFI.

So, my question is: does WFI have any driver for itself which I don't know?

By the way, I'm using CMSISv2LPC17xx which is included in "mcb1700.code.bundle.lpc1769.lpcxpresso".

Thanks in advance,

Best Regards,

Furkan Yuksel

[lpcware]

Content originally posted in LPCWare by furkan.yuksel on Thu Jul 14 02:02:24 MST 2011
Thank you Rob, I'll look at it to understand __WFI deeply ;-)

But my mistake was "again!" double underscore :-S I forgot to fix it in my main func so it does not recognize _WFI. I'm so sory for wasting your time and thank you so much for all both of your quick reponses.

Best Regards,

[lpcware]

Content originally posted in LPCWare by Rob65 on Thu Jul 14 01:39:04 MST 2011
Err,

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Quote:
When I clean and built again for the first time it gives warning.  However, when I rebuilt it for the second time warning disappears.

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This just means that your file is not compiled the second time.
A rebuild will only re-compile files that have changed since the last build, so if you did not change your file it does not rebuild and thus the warning does not appear.
You might want to read a manual on the Gnu compiler and how the build tools (like make) work.

The double underscore does a better trick - now the function can be found.

See also the timedwakeup example in the LPCXpresso1114-301_2011-01-27 example bundle that is included with LPCXpresso 4.0.5. That contains a complete example on how to use __WFI() and the DeepSleep mode.
Yes, I know: you are currently using the LPC17xx but unfortunately there is no timedwakeup example in the lpx17xx example bundle ...

Rob

[lpcware]

Content originally posted in LPCWare by furkan.yuksel on Thu Jul 14 00:32:27 MST 2011
It seems ok now. When I clean and built again for the first time it gives warning. However, when I rebuilt it for the second time warning disappears.

I didn't realize that WFI has duble underscores so I couldn't find it, now I found.

Thank you.

[lpcware]

Content originally posted in LPCWare by CodeRedSupport on Thu Jul 14 00:16:26 MST 2011
Err, no. I am saying that if you include LPC17xx.h then you shouldn't get the error. If you are then its sound like there is something wrong with the setup of your project.

It is impossible without seeing your project to say what the problem might be. In the first place I would check that your include paths actually point to the directory containing LPC17xx.h. Do you get any other warnings / errors?

Regards,
CodeRedSupport

[lpcware]

Content originally posted in LPCWare by furkan.yuksel on Wed Jul 13 23:58:48 MST 2011

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Quote: CodeRedSupport
However as long as you include "LPC17xx.h" (or the corresponding top level header if using a different part), then this should give you access to __WFI().

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So, You mean that I souldn't care this warning, because I include "LPC17xx.h".

Ok than, Thank you so much for your help :)

Best Regards,

[lpcware]

Content originally posted in LPCWare by CodeRedSupport on Wed Jul 13 23:52:50 MST 2011
The definition of __WFI() [I](note the double underscore character)[/I] is in one of the CMSIS header files (exact file actually depends upon CMSIS version).

However as long as you include "LPC17xx.h" (or the corresponding top level header if using a different part), then this should give you access to __WFI().

Regards,
CodeRedSupport.