PSoC5LP: How to use the comparator power down override?

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Anonymous
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What needs to be done in order for a comparator to continue operation while the PSoC5LP sleeps?

   

I have a switch whose level will be between 0 and 0.7V, which I connect to a comparator with a reverence of 0.256V. The output is taken to a Debouncer, with a 50Hz clock (permanently enabled). It's pos output is taken  to an isr. (see the attached graphic)

   

The comparator Speed is set to ultra low power and its PowerDownOverride is enabled.

   

The code:

   

    Pwr_SW_Comp_PwrDwnOverrideEnable();                //keep the power switch comparator running during sleep
    Pwr_SW_Comp_Start();
    isr_PWR_SW_StartEx(&Power_SW_ISR);

   

    while (1) {
        CyPmSleep(PM_SLEEP_TIME_NONE, PM_SLEEP_SRC_NONE);
    }

The ISR (Power_SW_ISR) is never entered, but if I comment out the CyPmSleep() line, it works fine.

   

What am I missing?

   

Any help would be appeciated.

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ETRO_SSN583
Level 9
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This may not be the specific problem, but are you taking into account this -

   

 

   

    

   

          

   

http://www.cypress.com/?rID=64554     AN77900

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ETRO_SSN583
Level 9
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I also see this in component datasheet -

   

 

   

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ETRO_SSN583
Level 9
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Here is an alternative way using SIO pin -

   

 

   

    

   

          

   

http://www.cypress.com/?rID=40989     AN60580

   

 

   

 

   

Regards, Dana.

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Anonymous
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Thanks Dana, I reckon something like that could be happening.

   

I need the comparator to switch at 550mV, so I use a DAC to provide that now, not a reference as stated previously.

   

There is a mention of the DAC going to sleep in the data sheet "In the DAC Bus mode, the output from the DAC is lost during sleep", but my data source is the CPU. There is no reference to sleep for that data source.

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Anonymous
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The reference to PSoC3 is confusing, as Creator 3 has a power down override enable button and it knows it's using a PSoC5. Normally I would expect the button to be greyed out if it weren't available.

   

Off topic, but how do you post pictures into a reply? (as opposed to attaching one)

   

Also, why isn't reply editing of my own posts available?

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ETRO_SSN583
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The forum software is 18'th century. It is not a true or capable HTML.

   

 

   

There is no option to edit replies or posts once posted.

   

 

   

Posting pics, I find that most, and thats not all, the time if I do a capture

   

in Adobe of a piece of doc, or screen copy,  and its the bottom most object

   

in a reply, that in Firefox you can paste the image. Works sometimes, sometimes

   

it does not.

   

 

   

Regards, Dana.

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Bob_Marlowe
Level 10
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Forum Software?

   

OK: Here it goes:

   

At "embedded world"-faire in Nuremberg I was introduced to Joseph L. McCarthy, Vice President, Corporate Communications and Marketing Communications, jmy@cypress.com (I've got his business card right here)

   

In the discussion I had with him, Mr. McCarthy claimed to be responsible for the (poor) forum software and when I stated that it is a shame(!!) for Cypress that in a "Developer Community" the software is not able to accept a code snippet without modifying it for bad he agreed. Then he said "I would like to have a Customer Community". I assume from this and my unanswered email to him that Mr. McCarthy thinks we are here in the CDC not "Customers" but something like "Hobbyists" or amateurs or students only.

   

Yes! Here are beginners, students, even pupils, but here are teachers, universities and DEVELOPERS!!!

   

Mr. McCarthy wants "Customers"? One way to get some is to "breed" them. That means to treat them politely and helpfully as my experience with Cypress has been so far.

   

So as a conclusion it looks like this forum software will not undergo any changes within this decade.

   

 

   

Bob (dissapointed)

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