5.3 CORDIC 使用说明

void RCC_Configuration()
{
    /* Enable DMA1 and CORDIC clock */
    RCC_EnableAHBPeriphClk(RCC_AHB_PERIPHEN_CORDIC | RCC_AHB_PERIPHEN_DMA1, ENABLE);
    /* When enabling CORDIC, HCLK DIV2 must be configured */
    RCC_ConfigPeriphClk(RCC_PERIPH_HCLK_DIV2);
}

    /* Get CORDIC read register (CORDIC_RDAT) address */
    rRegAddr = CORDIC_GetRegisterAddr(CORDIC_AS_DMA_SRCADDR);
    /* Get CORDIC write register (CORDIC_WDAT) address */
    wRegAddr = CORDIC_GetRegisterAddr(CORDIC_AS_DMA_DSTADDR);

    CORDIC_StructInit(&CORDIC_InitStructure);
    /* Select sine function */
    CORDIC_InitStructure.Function   = CORDIC_FUNCTION_SINE;
    /* Set max precision for Q1.31 sine */
    CORDIC_InitStructure.Precision  = CORDIC_PRECISION_6CYCLES;
    /* Enable Coordinate Limit */
    CORDIC_InitStructure.CodinLimit = CORDIC_CODIN_LIMIT_ENABLE;
    /* Enable Phase Limit */
    CORDIC_InitStructure.PhaseLimit = CORDIC_PHASE_LIMIT_ENABLE;
    /* Configure CORDIC */
    CORDIC_Init(&CORDIC_InitStructure);

    /* Reset DMA1 channel 1 */
    DMA_DeInit(DMA1_CH1);
    /* Initialize the DMA parameter structure */
    DMA_StructInit(&DMA_InitStructure);
    DMA_InitStructure.PeriphAddr     = SrcAddr;
    DMA_InitStructure.MemAddr        = (uint32_t)DstAddr;
    DMA_InitStructure.Direction      = DMA_DIR_PERIPH_SRC;
    DMA_InitStructure.BufSize        = DataLen;
    DMA_InitStructure.MemoryInc      = DMA_MEM_INC_ENABLE;
    DMA_InitStructure.PeriphDataSize = DMA_PERIPH_DATA_WIDTH_WORD;
    DMA_InitStructure.MemDataSize    = DMA_MEM_DATA_WIDTH_WORD;
    /* Initialize DMA1 channel 1 */
    DMA_Init(DMA1_CH1, &DMA_InitStructure);
    /* CORDIC read channel mapping */
    DMA_RequestRemap(DMA_REMAP_CORDIC_RD, DMA1_CH1, ENABLE);
    /* Enable DMA1 channel 1 transfer completion interrupt */
    DMA_ConfigInt(DMA1_CH1, DMA_INT_TXC, ENABLE);
    /* Enable DMA1 channel 1 */
    DMA_EnableChannel(DMA1_CH1, ENABLE);

    /* Configure DMA read channel */
    DMA_ReadConfiguration(rRegAddr, aCalResult, ARRAY_SIZE);
    /* Enable CORDIC DMA read request */
    CORDIC_DMAReadRequestCmd(ENABLE);

    /* Configure DMA write channel */
    DMA_WriteConfiguration(aInData, wRegAddr, ARRAY_SIZE);
    /* Enable CORDIC DMA write request */
    CORDIC_DMAWriteRequestCmd(ENABLE);

    while (CORDIC_GetFlagStatus(CORDIC_FLAG_RRF) == RESET)
    {
        /* Do nothing */
    }
    
    /* Compare CORDIC results to the reference values */
    for (i = 0; i < ARRAY_SIZE; i++)
    {
        /* Check the data results sequentially */
        if (CheckResidualError(aCalResult[i], aRefResult[i], MAX_RESIDUAL_ERROR_18) == 0U)
        {
            log_info("Error[%d]\n", i);
            while (1);
        }
    }

void RCC_Configuration()
{
    /* Enable CORDIC clock */
    RCC_EnableAHBPeriphClk(RCC_AHB_PERIPHEN_CORDIC, ENABLE);
    /* When enabling CORDIC, HCLK DIV2 must be configured */
    RCC_ConfigPeriphClk(RCC_PERIPH_HCLK_DIV2);
}

    CORDIC_StructInit(&CORDIC_InitStructure);
    /* Select sine function */
    CORDIC_InitStructure.Function   = CORDIC_FUNCTION_SINE;
    /* Set max precision for Q1.31 sine */
    CORDIC_InitStructure.Precision  = CORDIC_PRECISION_6CYCLES;
    /* Enable Coordinate Limit */
    CORDIC_InitStructure.CodinLimit = CORDIC_CODIN_LIMIT_ENABLE;
    /* Enable Phase Limit */
    CORDIC_InitStructure.PhaseLimit = CORDIC_PHASE_LIMIT_ENABLE;
    /* Configure CORDIC */
    CORDIC_Init(&CORDIC_InitStructure);

    /* Enable CORDIC interrupt */
    CORDIC_InterruptCmd(CORDIC_INT, ENABLE);

    for (wArrayIndex = 0; wArrayIndex < ARRAY_SIZE; wArrayIndex++)
    {
        /* Write data to be calculated */
        CORDIC_WriteData((uint32_t *)&aInData[wArrayIndex]);
    }

void Cordic_IRQ_IRQHandler(void)
{
    if (CORDIC_GetFlagStatus(CORDIC_FLAG_RRF) != RESET)
    {
        /* Read calculation results */
        /* The RRF flag will be cleared after reading the data register */
        CORDIC_ReadData((uint32_t *)&aCalResult[rArrayIndex++]);
    }
}

void RCC_Configuration(void)
{
    /* Enable CORDIC clock */
    RCC_EnableAHBPeriphClk(RCC_AHB_PERIPHEN_CORDIC, ENABLE);
    /* When enabling CORDIC, HCLK DIV2 must be configured */
    RCC_ConfigPeriphClk(RCC_PERIPH_HCLK_DIV2);
}

    CORDIC_StructInit(&CORDIC_InitStructure);
    /* Select sine function */
    CORDIC_InitStructure.Function   = CORDIC_FUNCTION_SINE;
    /* Set max precision for Q1.31 sine */
    CORDIC_InitStructure.Precision  = CORDIC_PRECISION_6CYCLES;
    /* Select floating-point input */
    CORDIC_InitStructure.InSelect   = CORDIC_INPUT_FLOAT;
    /* Select floating-point output */
    CORDIC_InitStructure.OutSelect  = CORDIC_OUTPUT_FLOAT;
    /* Enable Coordinate Limit */
    CORDIC_InitStructure.CodinLimit = CORDIC_CODIN_LIMIT_ENABLE;
    /* Enable Phase Limit */
    CORDIC_InitStructure.PhaseLimit = CORDIC_PHASE_LIMIT_ENABLE;
    /* Configure CORDIC */
    CORDIC_Init(&CORDIC_InitStructure);

    /* Enable CORDIC interrupt */
    CORDIC_InterruptCmd(CORDIC_INT, ENABLE);

    for (i = 0; i < ARRAY_SIZE; i++)
    {
        /* Random generation of input data */
        aInData[i] = -1.0f + ((float)(rand() % 1999)) * 0.001f;

        /* Software calculation results */
        aRefResult[i] = sinf(aInData[i] * PI);
    }

void Cordic_IRQ_IRQHandler(void)
{
    if (CORDIC_GetFlagStatus(CORDIC_FLAG_RRF) != RESET)
    {
        /* Read calculation results */
        /* The RRF flag will be cleared after reading the data register */
        CORDIC_ReadData((uint32_t *)&aCalResult[rArrayIndex++]);
    }
}