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    #define DMA_MAX (4096-4)
	
    volatile lldesc_t* head_a;    // dma descriptor a.
    volatile lldesc_t* head_b;    // dma descriptor b. 
	
    lldesc_t dma_desc_buf_a[8];     
    lldesc_t dma_desc_buf_b[8];    
	
    head_a = (lldesc_t*) &dma_desc_buf_a[0];
    head_b = (lldesc_t*) &dma_desc_buf_b[0];
	
	
    // buffer_a address 0x3FFA_E000 
    // buffer_b  address 0x3FFA_E000 + 32768	
    uint8_t buffer_a[30720];    // 32KBytes = 32768 bytes   ????  . Especificar o endereço de um banco de memoria de 32K.
    uint8_t buffer_b[30720];    // 32KBytes = 32768 bytes   ????  . Especificar o endereço de um banco de memoria de 32K.
		
	
    // 1/10 de um display( 480 linhas por 320 colunas, modo retrato ), 16 bits por pixel(2 bytes) eh igual a 48 linhas com 320 colunas.
    // 48 * 320 = 15360 pixels * 2 bytes/pixel = 15360*2 = 30720 bytes. 
    // 7 descriptors com 4092 bytes = 28644 bytes.
    // 1 descriptor  com 2076 bytes = 2076 bytes.
    // 28644 + 2076 = 30720 bytes.	
		
    // I will do the same with dma_desc_buf_b[i]
    	
    void createStaticLinkedList()
    {

        for ( int i = 0 ; i < 8-1 ; i++ )    // 0 à 6.
	{
	
	    dma_desc_buf_a[i].size = 4092;    // The size must be word-aligned. The size of the buffer corresponding to the current linked list.
            dma_desc_buf_a[i].length = 4092;  // The number of valid bytes in the buffer corresponding to the current linked list. The field value indicates the number of bytes to be transferred to/from the buffer denoted by word DW1.	
            dma_desc_buf_a[i].offset = 0;	
	    dma_desc_buf_a[i].sosf = 0;	
	    dma_desc_buf_a[i].eof = 0;	       // indica que não eh o final da lista. 
	    dma_desc_buf_a[i].owner = 1;      // the allowed operator is the DMA controller.		
	    dma_desc_buf_a[i].buf = (uint8_t*) ( ( &buffer_a ) + ( 4092 * i ) );  		
	    dma_desc_buf_a[i].qe.stqe_next = ( lldesc_t* ) &dma_desc_buf_a[ i+1 ];
	
        }
	
	dma_desc_buf_a[7].size = 2076;    // The size must be word-aligned. Eu posso definir 4092 aqui, porem o dma soh ira enviar 2076 bytes. Se eu definir 4092 aqui estarei alocando um banco de memoria ram(32KBytes) somente para este uso.
	dma_desc_buf_a[7].length = 2076;	
	dma_desc_buf_a[7].offset = 0;	
	dma_desc_buf_a[7].sosf = 0;	
	dma_desc_buf_a[7].eof = 1;	    // indica que eh o final da lista. 
	dma_desc_buf_a[7].owner = 1;    // the allowed operator is the DMA controller.		
	dma_desc_buf_a[7].buf = (uint8_t*) ( ( &buffer_a ) + ( 4092 * 7 ) );  		
	dma_desc_buf_a[7].qe.stqe_next = ( lldesc_t* ) NULL;    // ultimo nó da lista ligada.	
}