Lpc2000

Hi all,

       In my application I am using INT1 as -ve edge trigger interrupt
( PINSEL0_bit.P0_3 = 0x3).I also need to check the status of the same 
pin by configuring it as a GPIO( PINSEL0_bit.P0_3 = 0x0).
       But when i switching between GPIO & INT1 by using PINSEL ,I am 
getting INT1 interrupt (unnecessary interrupt).
       What may be the reason for it & how should i overcome it.  
     
Thanks & Regards,

Pandurang S.

Hi,

I posted a message regarding this some time ago:

http://groups.yahoo.com/group/lpc2000/message/11212

There are several possible work-arounds:

1. disable interrupt when reading state of pin
2. just take the extra interrupt, knowing it's spurious
3. route signal to a 2nd GPIO pin, and use that to read state

The first two work OK in general, but there's a risk you'll miss a 
genuine interrupt. Safest option (that I can think of) is 3.

I'm a bit surprised that this hasn't been documented by Philips at 
this stage: it's been known for some time.

Brendan


--- In lpc2000@yahoogroups.com, "topandurangs" <pandurang@...> wrote:
>
> Hi all,
> 
>        In my application I am using INT1 as -ve edge trigger 
interrupt
> ( PINSEL0_bit.P0_3 = 0x3).I also need to check the status of the 
same 
> pin by configuring it as a GPIO( PINSEL0_bit.P0_3 = 0x0).
>        But when i switching between GPIO & INT1 by using PINSEL ,I 
am 

> getting INT1 interrupt (unnecessary interrupt).
>        What may be the reason for it & how should i overcome it.  
>      
> Thanks & Regards,
> 
> Pandurang S.
>