DMA 循环发送如何设置

不知道这个 demo 对你有没有帮助

/***************************************************************************** 
* 
* File Name :  main. c
* 
* Description:  main 
* 
* Copyright  (c)  2014 Winner Micro Electronic Design Co. ,  Ltd.  
* All rights reserved.  
* 
* Author :  dave
* 
* Date :  2014-6-14
*****************************************************************************/ 
#include "wm_include. h"
#include "wm_cpu. h"
#include "wm_dma. h"

u8 send_data[8] = {0};  
u8 recv_data[8] = {0};  

static void gpio_dma_callback (void) 
{
    printf ("--- %s\r\n", __func__) ; 
    printf ("recv_data: ") ; 
    for (int i = 0;  i   8;  i++) printf ("%02X ", recv_data[i]) ; 
    printf ("\n") ; 
}


void UserMain (void) 
{
    extern void tls_sys_clk_set () ; 
    extern u32 tls_mem_get_avail_heapsize (void) ; 
    tls_sys_clk_set (CPU_CLK_80M) ; 

    printf ("\n             \\\\\\|///\n") ; 
    printf ("           \\\\  . -. -  //\n") ; 
    printf (".             (  . @. @  )   \n") ; 
    printf ("+-------oOOo----- (_) -----oOOo---------+\n\n") ; 
    printf (" ---  Compile "__DATE__",  "__TIME__"\n") ; 
    printf (" ---  %s. c\r\n", __func__) ; 
    printf (" ---  GetHeap: %d\n", tls_mem_get_avail_heapsize () ) ; 
    printf ("\n+---------------------Oooo------------+\n") ; 


    u8 dmaCh; 
    struct tls_dma_descriptor DmaDesc; 

    printf ("send_data: ") ; 
    for (int i = 0;  i   8;  i++) printf ("%02X ", send_data[i]) ; 
    printf ("\n") ; 

    printf ("recv_data: ") ; 
    for (int i = 0;  i   8;  i++) printf ("%02X ", recv_data[i]) ; 
    printf ("\n") ; 

    for (int i = 0;  i    (sizeof (send_data) /sizeof (char) ) ;  i++) 
    {
        send_data[i] = i; 
    }
    printf ("send_data: ") ; 
    for (int i = 0;  i   8;  i++) printf ("%02X ", send_data[i]) ; 
    printf ("\n") ; 

    printf ("recv_data: ") ; 
    for (int i = 0;  i   8;  i++) printf ("%02X ", recv_data[i]) ; 
    printf ("\n") ; 

    dmaCh = tls_dma_request (1,  0) ; 
    
    printf ("send_data: %08X\n", &send_data[0]) ; 

    DmaDesc. src_addr  = send_data; 
    DmaDesc. dest_addr = recv_data; 

    printf ("src_addr:  %08X\n", DmaDesc. src_addr) ; 
    printf ("dest_addr: %08X\n", DmaDesc. dest_addr) ; 

    DmaDesc. dma_ctrl = TLS_DMA_DESC_CTRL_DEST_ADD_INC |TLS_DMA_DESC_CTRL_SRC_ADD_INC |  TLS_DMA_DESC_CTRL_BURST_SIZE1 | TLS_DMA_DESC_CTRL_DATA_SIZE_BYTE | TLS_DMA_DESC_CTRL_TOTAL_BYTES (8) ; 
    DmaDesc. valid = TLS_DMA_DESC_VALID; 
    DmaDesc. next = NULL; 
    
    tls_dma_start (dmaCh,  &DmaDesc,  0) ; 
    tls_dma_irq_register (dmaCh,   (void  (*) ) gpio_dma_callback,  NULL,  TLS_DMA_IRQ_TRANSFER_DONE) ; 

}