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Re: Problem reading buttons on AT91sam7s-ek


On Mon, Oct 01, 2007 at 02:27:32PM +0200, Rasmus Stougaard wrote:
> Hi
> 
> I am trying to read the state of the buttons on a AT91sam7s-ek
> evaluation kit from atmel.
> 
> I figure that something like:
> 
>     cyg_uint32 value;
>     HAL_ARM_AT91_GPIO_CFG_DIRECTION(AT91_GPIO_PA20, AT91_PIN_IN);
>     HAL_ARM_AT91_GPIO_CFG_PULLUP(AT91_GPIO_PA20, AT91_PIN_PULLUP_ENABLE);
>     HAL_ARM_AT91_GPIO_GET(AT91_GPIO_PA20, value);
>     trace(" AT91_GPIO_PA20 %d\n", value);
> 
> Should configure the pin for input and print the current state of the
> of the pin.

In general that looks O.K. Have you tried the other 3 switches?

One idea i have. Is the clock to the GPIO device enabled? Check bit
AT91_PMC_PCER_PIOA in AT91_PMC_PCER. Without a clock you can do
output. But to do input you need the clock enabled.

  Andrew
 

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