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Altera_Forum
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17 years ago

Interruption program

Hello, I am trying to do an interruption of a video signal. I am using the hsmc quad video card of Bitec associated to a cyclone III C25 Altera card. An interruption is supposed to be generated...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
17 years ago

Hi,

About the context forget it for the moment. It is not compulsory to use it. For example you can register the ISR like that. 

 alt_irq_register( BUTTON_PIO_IRQ, 0, handle_button_interrupts );
And in the ISR function, you do not use the variable context. But it is not the problem, so forget it for the moment.

So if I understand well, the interrupt is active when you have activity on the LSB of your video port. What is the name of this signal on your design ?

To be sure if you have an interruption and the program goes to the ISR, you can switch on a LED in the ISR. Like that you know rapidly if the problem is here or not.

After, as it is a the video port is a PIO port, like in your design with the buttons, the principle is the same. In the ISR, you have to write on the edgecapture register for PIO port (IOWR_ALTERA_AVALON_PIO_EDGE_CAP(VIDEO_1_BASE, 0xFF)).

Jérôme