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标题: EBI_Open();函数的执行速度，请问有明确数据吗？ [打印本页]

作者: 匿名 时间: 2025-1-21 11:22
标题: EBI_Open();函数的执行速度，请问有明确数据吗？
#define EBI_TIMING_FASTEST    0x0UL /*!< EBI timing is the fastest \hideinitializer */
#define EBI_TIMING_VERYFAST    0x1UL /*!< EBI timing is very fast \hideinitializer */
#define EBI_TIMING_FAST       0x2UL /*!< EBI timing is fast \hideinitializer */
#define EBI_TIMING_NORMAL    0x3UL /*!< EBI timing is normal  \hideinitializer */
#define EBI_TIMING_SLOW       0x4UL /*!< EBI timing is slow \hideinitializer */
#define EBI_TIMING_VERYSLOW    0x5UL /*!< EBI timing is very slow \hideinitializer */
#define EBI_TIMING_SLOWEST    0x6UL /*!< EBI timing is the slowest \hideinitializer */

EBI_Open(EBI_BANK0, EBI_BUSWIDTH_16BIT, EBI_TIMING_NORMAL, 0, EBI_CS_ACTIVE_LOW);

另外，这个还需要单独设置吗？
#define EBI_MCLKDIV_1          0x0UL /*!< EBI output clock(MCLK) is HCLK/1 \hideinitializer */
#define EBI_MCLKDIV_2          0x1UL /*!< EBI output clock(MCLK) is HCLK/2 \hideinitializer */
#define EBI_MCLKDIV_4          0x2UL /*!< EBI output clock(MCLK) is HCLK/4 \hideinitializer */
#define EBI_MCLKDIV_8          0x3UL /*!< EBI output clock(MCLK) is HCLK/8 \hideinitializer */
#define EBI_MCLKDIV_16       0x4UL /*!< EBI output clock(MCLK) is HCLK/16 \hideinitializer */
#define EBI_MCLKDIV_32       0x5UL /*!< EBI output clock(MCLK) is HCLK/32 \hideinitializer */
#define EBI_MCLKDIV_64       0x6UL /*!< EBI output clock(MCLK) is HCLK/64 \hideinitializer */
#define EBI_MCLKDIV_128       0x7UL /*!< EBI output clock(MCLK) is HCLK/128 \hideinitializer */

作者: chrishu 时间: 2025-1-22 11:42
EBI_Open函数里的宏定义时序快慢只是软件里用的而已。
实际快慢看EBI_Open函数里的每个case下设置的MCLK分频系数和时序控制的设置。MCLKDIV的分频系数在open函数里已经设置过了。
switch(u32TimingClass)
{
case EBI_TIMING_FASTEST:
      *pu32EBICTL = (*pu32EBICTL & ~(EBI_CTL_MCLKDIV_Msk | EBI_CTL_TALE_Msk)) |
                  (EBI_MCLKDIV_1 << EBI_CTL_MCLKDIV_Pos) | //1分频
                  (u32CSActiveLevel << EBI_CTL_CSPOLINV_Pos) | EBI_CTL_EN_Msk;
      //时序控制
      *pu32EBITCTL = 0x0U;
      break;

case EBI_TIMING_VERYFAST:/
      *pu32EBICTL = (*pu32EBICTL & ~(EBI_CTL_MCLKDIV_Msk | EBI_CTL_TALE_Msk)) |
                  (EBI_MCLKDIV_1 << EBI_CTL_MCLKDIV_Pos) | //1分频
                  (u32CSActiveLevel << EBI_CTL_CSPOLINV_Pos) | EBI_CTL_EN_Msk |
                  (0x3U << EBI_CTL_TALE_Pos) ;//地址锁存时间 = 4MCLK
      //时序控制
      *pu32EBITCTL = 0x03003318U;
      break;

......
}

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