CC2541 SNV扩容

SNV可以使用的空间只有4K，在不是用OTA功能的情况下，如何把剩余的空间使用SNV管理使用呢？

官方有 dma方式操作内部flash的例程，可以下载。

下载地址

http://www.ti.com/product/CC2541/toolssoftware

把第96page~124page拿来存储数据，自己写了个FLASH写函数，使用DMA1，无备份。

uint8 BSPFlash_Write(uint16 offset, uint8 *buf, uint16 len)
{
    halDMADesc_t *ch;
    
    ch = HAL_DMA_GET_DESC1234( FLASH_DMA_CH );
    
    HAL_DMA_SET_SOURCE( ch, buf );
    HAL_DMA_SET_DEST( ch, &FWDATA );
    HAL_DMA_SET_VLEN( ch, HAL_DMA_VLEN_USE_LEN );
    HAL_DMA_SET_LEN( ch, len );
    HAL_DMA_SET_WORD_SIZE( ch, HAL_DMA_WORDSIZE_BYTE );
    HAL_DMA_SET_TRIG_MODE( ch, HAL_DMA_TMODE_SINGLE );
    HAL_DMA_SET_TRIG_SRC( ch, HAL_DMA_TRIG_FLASH );
    HAL_DMA_SET_SRC_INC( ch, HAL_DMA_SRCINC_1 );
    HAL_DMA_SET_DST_INC( ch, HAL_DMA_DSTINC_0 );
    HAL_DMA_SET_IRQ( ch, HAL_DMA_IRQMASK_DISABLE );
    HAL_DMA_SET_M8( ch, HAL_DMA_M8_USE_8_BITS );
    HAL_DMA_SET_PRIORITY( ch, HAL_DMA_PRI_HIGH);
    
    // Waiting for the flash controller to be ready. 
    while (FCTL & FCTL_BUSY);
  
    /* Configuring the flash controller. 
     * FADDRH:FADDRL: point to the area in flash to write to.
     */
    uint16 addr, page;
    page = SPACE_START_PAGE + (offset / HAL_FLASH_PAGE_SIZE);
    addr = ((offset % HAL_FLASH_PAGE_SIZE) >> 2) + (page << 9);    // You address 32-bit words through the flash controller.
    
    FADDRH = (addr >> 8) & 0x00FF;
    FADDRL = addr & 0x00FF;
  
    uint8 firstByte = 0;
    BSPFlash_Read(offset, &firstByte, 1);
    if(firstByte != 0xFF){
        FCTL |= FCTL_ERASE;
        while (FCTL & FCTL_BUSY);
    }
  
    HAL_DMA_CLEAR_IRQ(FLASH_DMA_CH);
    // Arm the DMA channel, takes 9 system clock cycles.
    HAL_DMA_ARM_CH(FLASH_DMA_CH);
    asm("nop");asm("nop");asm("nop");// 9 NOPs
    asm("nop");asm("nop");asm("nop");
    asm("nop");asm("nop");asm("nop");
  
    // Enable flash write. Generates a DMA trigger.
    FCTL |= FCTL_WRITE;
  
    // Wait until flash controller not busy.
    while (FCTL & (FCTL_BUSY | FCTL_FULL));

    return 1;
}