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Dumb question of the day, about pointers
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Dumb question of the day, about pointers

porcine_aviator posted on 12 Jun 2012 11:35 PM PST
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58 Forum Posts

Hello all.

In my isr_1.c file, I wish (for various reasons) to assign a pointer to a specific spot in the SRAM.

What I'm doing is calculating an index (based on the number of times I've entered the ISR) and adding that to a static base address, as in:

uint16 offset;

uint8 *foo;

foo = 0x20000000 + offset;

The complier issues a warning, stating that I'm creating a pointer from an int without a cast.

Is there a more "elegant" or "kosher" way to do this? I am intentionally putting things into this portion of SRAM in order to avoid conflicting with anything related to program execution.

Your thoughts are appreciated, thanks.




Re: Dumb question of the day, about pointers

Bob Marlowe posted on 12 Jun 2012 02:31 AM PST
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1768 Forum Posts

You forgot to mention in which of the three worlds you live: PSoC 1, PSoC3 or PSoC5.

for PSoC3 a solution could be:

CYXDATA char MyMem[1 ] _at_ 0x2000;

and later on:

   for(ii=0;ii<1000;MyMem[ii++]=0);

 

Bob



Re: Dumb question of the day, about pointers

Bob Marlowe posted on 12 Jun 2012 02:32 AM PST
Top Contributor
1768 Forum Posts


Re: Dumb question of the day, about pointers

Bob Marlowe posted on 12 Jun 2012 05:22 AM PST
Top Contributor
1768 Forum Posts

Sorry, the above post lacks some information.

 

This should work for PSoC3 and 5

CYXDATA *MyMem = (void *)0x2000;  // With initialization

Bob






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