Issue with retriving images from OV2640 and Pico

[Edenane]

Hi, When retreiving images using the HostApp and they are small, there are no issues retreiving the images. However, if the requested resolution is 1024x768 the images are about 90% of the time have corruption issues:

Any idea what could be causing this? It's attached to a OV2640.

[Edenane]

I solved this by reading byte by byte from the SPI rather than all at once, so I changed this function:

uint8_t read_fifo_burst(ArduCAM myCAM)
{
  int i , count;
  int length = myCAM.read_fifo_length();
  uint8_t * imageBuf =(uint8_t *) malloc(length*sizeof(uint8_t));
  i = 0 ;
  myCAM.CS_LOW();
  myCAM.set_fifo_burst();//Set fifo burst mode
  spi_read_blocking(SPI_PORT, BURST_FIFO_READ,imageBuf, length);
  myCAM.CS_HIGH();
  SerialUsb(imageBuf, length);
  free(imageBuf);
  return 1;
}

to

uint8_t read_fifo_burst(ArduCAM myCAM)
{
  int i;
  int length = myCAM.read_fifo_length();
  uint8_t VAL;
  myCAM.CS_LOW();
  myCAM.set_fifo_burst();//Set fifo burst mode
  for (i = 0; i < length; i++){
    spi_read_blocking(SPI_PORT, BURST_FIFO_READ,&VAL, 1);
    sleep_us(12);
    SerialUsb(&VAL, 1);
  }
  return 1;

This does slow down retriving the images but worked every time.