在主程序中添加SDRAM的初始化代码：
#define REFRESH_COUNT 677
#define SDRAM_TIMEOUT ((uint32_t)0xFFFF)
#define SDRAM_MODEREG_BURST_LENGTH_1 ((uint16_t)0x0000)
#define SDRAM_MODEREG_BURST_LENGTH_2 ((uint16_t)0x0001)
#define SDRAM_MODEREG_BURST_LENGTH_4 ((uint16_t)0x0002)
#define SDRAM_MODEREG_BURST_LENGTH_8 ((uint16_t)0x0004)
#define SDRAM_MODEREG_BURST_TYPE_SEQUENTIAL ((uint16_t)0x0000)
#define SDRAM_MODEREG_BURST_TYPE_INTERLEAVED ((uint16_t)0x0008)
#define SDRAM_MODEREG_CAS_LATENCY_2 ((uint16_t)0x0020)
#define SDRAM_MODEREG_CAS_LATENCY_3 ((uint16_t)0x0030)
#define SDRAM_MODEREG_OPERATING_MODE_STANDARD ((uint16_t)0x0000)
#define SDRAM_MODEREG_WRITEBURST_MODE_PROGRAMMED ((uint16_t)0x0000)
#define SDRAM_MODEREG_WRITEBURST_MODE_SINGLE ((uint16_t)0x0200)
void MX_SDRAM_InitEx(void)
{
__IO uint32_t tmpmrd = 0;
/* Step 1: Configure a clock configuration enable command */
Command.CommandMode = FMC_SDRAM_CMD_CLK_ENABLE;
Command.CommandTarget = FMC_SDRAM_CMD_TARGET_BANK1;
Command.AutoRefreshNumber = 1;
Command.ModeRegisterDefinition = 0;
/* Send the command */
HAL_SDRAM_SendCommand(&hsdram1, &Command, SDRAM_TIMEOUT);
/* Step 2: Insert 100 us minimum delay */
/* Inserted delay is equal to 1 ms due to systick time base unit (ms) */
HAL_Delay(1);
/* Step 3: Configure a PALL (precharge all) command */
Command.CommandMode = FMC_SDRAM_CMD_PALL;
Command.CommandTarget = FMC_SDRAM_CMD_TARGET_BANK1;
Command.AutoRefreshNumber = 1;
Command.ModeRegisterDefinition = 0;
/* Send the command */
HAL_SDRAM_SendCommand(&hsdram1, &Command, SDRAM_TIMEOUT);
/* Step 4: Configure an Auto Refresh command */
Command.CommandMode = FMC_SDRAM_CMD_AUTOREFRESH_MODE;
Command.CommandTarget = FMC_SDRAM_CMD_TARGET_BANK1;
Command.AutoRefreshNumber = 4;
Command.ModeRegisterDefinition = 0;
/* Send the command */
HAL_SDRAM_SendCommand(&hsdram1, &Command, SDRAM_TIMEOUT);
/* Step 5: Program the external memory mode register */
tmpmrd = (uint32_t)SDRAM_MODEREG_BURST_LENGTH_4 |\
SDRAM_MODEREG_BURST_TYPE_SEQUENTIAL |\
SDRAM_MODEREG_CAS_LATENCY_2 |\
SDRAM_MODEREG_OPERATING_MODE_STANDARD |\
SDRAM_MODEREG_WRITEBURST_MODE_SINGLE;
Command.CommandMode = FMC_SDRAM_CMD_LOAD_MODE;
Command.CommandTarget = FMC_SDRAM_CMD_TARGET_BANK1;
Command.AutoRefreshNumber = 1;
Command.ModeRegisterDefinition = tmpmrd;
/* Send the command */
HAL_SDRAM_SendCommand(&hsdram1, &Command, SDRAM_TIMEOUT);
/* Step 6: Set the refresh rate counter */
/* Set the device refresh rate */
HAL_SDRAM_ProgramRefreshRate(&hsdram1, REFRESH_COUNT);
}
|
楼主
