Interrupt in uC/OS-II

Altera_Forum · ‎04-04-2012

Hi,

I use OSSemPost in my Interrupt ISR as follow:

volatile int frame_ready_edge_capture;
INT8U error_code;
static void handle_frame_ready_interrupts(void* context, alt_u32 id)
{
    /* Cast context to dval_edge_capture's type.
    * It is important to keep this volatile,
    * to avoid compiler optimization issues.
    */
    volatile int* frame_ready_edge_capture_ptr = (volatile int*) context;
    /* Store the value in the dval's edge capture register in *context. */
    *frame_ready_edge_capture_ptr = IORD_ALTERA_AVALON_PIO_EDGE_CAP(FRAME_READY_IRQ_PIO_BASE);
    /* Reset the dval's edge capture register. */
    IOWR_ALTERA_AVALON_PIO_EDGE_CAP(FRAME_READY_IRQ_PIO_BASE, 0);
    /*
     * Read the PIO to delay ISR exit. This is done to prevent a spurious
     * interrupt in systems with high processor -> pio latency and fast
     * interrupts.
     */
    IORD_ALTERA_AVALON_PIO_EDGE_CAP(FRAME_READY_IRQ_PIO_BASE);
    error_code = OSSemPost(FVSendVideoDataSem);
    alt_uCOSIIErrorHandler(error_code, 0);
    FrameDown= 1;
    IOWR_ALTERA_AVALON_PIO_DATA(LED_PIO_BASE, led0^=1);
    //IOWR_ALTERA_AVALON_PIO_DATA(LED_PIO_BASE, led0+=1);
    frame_ready_edge_capture= 0;
}

and in my Task:

void SendVideoTask()
{
    INT16U rgb_tx_buf_cnt= 0;
    INT16U cntTCPFrame= 0;
    INT16U cntVideoFrame= 0;
    INT32U Data_Pixel;
    INT16U Data_Pixel_16bit;
    alt_u8 dot, Dot, packet= 0, DotCnt= 0;
    INT8U error_code, led= 0;
    alt_u16 x, y;
.....
.....
        OSSemPend(FVSendVideoDataSem, 0, &error_code);
        alt_uCOSIIErrorHandler(error_code, 0);
        for(y= 0; y<RAW; y++)
        {
            for(x= 0; x<COL; x++)
            {
                Data_Pixel= IORD_MY_RGB2YUV_IP_DATA(MY_RGB2YUV_BASE);                    // read 24bit RGB value
                Dot= Data_Pixel;                                                        // isolate B
                Dot= Data_Pixel >> MY_RGB2YUV_IP_DATA_G_OFST;                        // isolate G
                Dot= Data_Pixel >> MY_RGB2YUV_IP_DATA_R_OFST;                        // isolate R
                Dot= Dot >> 3;                                                    // make 5bit for Blue
                Dot= Dot >> 2;                                                    // make 6bit for Green
                Dot= Dot >> 3;                                                    // make 5bit for Red
                Data_Pixel_16bit= 0;
                Data_Pixel_16bit |= Dot << 11 | Dot << 5 | Dot;                // merge all in 16bit RGB value
                alt_up_pixel_buffer_dma_draw(pixel_buf_dev, Data_Pixel_16bit, x, y);    // draw pixel on VGA for debug
            }
        }

the LED_PIO works well, but my Interrupt with OSSemPost in the ISR and OSSemPend in my Task dosn't work.

Could someone say me what I mak ewrong???

Thanks.

Antonio

Altera_Forum · ‎04-04-2012

I watch wrong in the Signal Tap II, my code work good....

sorry

Altera_Forum · ‎04-05-2012

You must write ones, not zeros, in order to clear edge capture and acknowledge the irq.

IOWR_ALTERA_AVALON_PIO_EDGE_CAP(FRAME_READY_IRQ_PIO_BASE, 1);

Otherwise the irq would continuously retrigger.

Altera_Forum · ‎08-05-2013

I suggest to disable the interrupt first and re enable it at last with [h=2]alt_irq_enable(IRQ number)[/h]

This will avoid re-triggering problem and make sure that ISR executed successfully