How shall i can generate an interrupt on the falling edge of a Comparator?

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Anonymous
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Hello Everyone,

   

I want to fire an interrupt on the falling edge of the comparator. I directly attached an interrupt source to a comparator(see attachment), but it only has a rising edge option.

   

I don't really understand the option "LEVEL".

   

Looking forward for your help!

   

Regards

   

Awais

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Bob_Marlowe
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Set the polarity of the comparator to "inverted".

   

 

   

Bob

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Anonymous
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Thank you, Bob, for your reply.

   

Sorry, One information is missing : I want to generate the interrupt on the rising and falling edge of the comparator.

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Bob_Marlowe
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Use an inverter and two isrs. Does that work?

   

 

   

Bob

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Anonymous
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I haven't tested that. 

   

But I think it will not work! Because according to datasheet:

   

Inverting: Output goes high when the positive input is less than the negative input.

   

Non-Inverting (default):  Output goes high when positive input is greater than negative input.

   

Also the question is, how the ISR will know when the falling edge of the signal is there? because if we see in the properties of the isr, it has three options, derived, rising and level.

   

I have no idea about "level".

   

Awais

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Bob_Marlowe
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Are you using comparator v 1.20? If not, update!!!

   

 

   

Bob

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Anonymous
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No, Its 2.0

   

 

   

Awais

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Bob_Marlowe
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Update!!!! Are you using Creator 3.3 CP3 (Creator -> Help -> About) If not, update first Creator to latest!!!

   

 

   

Bob

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Anonymous
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I updated all components. But I think v 2.0 is the latest one.

   

Yes, I am Using PSoC Creator  3.3 SP2 (3.3.0.9604).

   

Awais

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Bob_Marlowe
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Sorry, my fault. I was on PSoC4 which has a different comparator. So you need to connect two isr components to the comparator output and the inverted comparator output using a NOT gate.

   

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Anonymous
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Ahan!

   

Ok, I will try this 🙂

   

Thankyou Bob

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