rt-thread-official/bsp/swm320/libraries/SWM320_StdPeriph_Driver/SWM320_sdram.c

117 lines
4.5 KiB
C
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/******************************************************************************************************************************************
* 文件名称: SWM320_sdram.c
* 功能说明: SWM320单片机的SDRAM驱动程序
* 技术支持: http://www.synwit.com.cn/e/tool/gbook/?bid=1
* 注意事项:
* 版本日期: V1.1.0 2017年10月25日
* 升级记录:
*
*
*******************************************************************************************************************************************
* @attention
*
* THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS WITH CODING INFORMATION
* REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE TIME. AS A RESULT, SYNWIT SHALL NOT BE HELD LIABLE
* FOR ANY DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING FROM THE CONTENT
* OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE CODING INFORMATION CONTAINED HEREIN IN CONN-
* -ECTION WITH THEIR PRODUCTS.
*
* COPYRIGHT 2012 Synwit Technology
*******************************************************************************************************************************************/
#include "SWM320.h"
#include "SWM320_sdram.h"
/******************************************************************************************************************************************
* 函数名称: SDRAM_Init()
* 功能说明: SDRAM控制器初始化
* 输 入: SDRAM_InitStructure * initStruct 包含 SDRAM 控制器相关设定值的结构体
* 输 出: 无
* 注意事项: 无
******************************************************************************************************************************************/
void SDRAM_Init(SDRAM_InitStructure *initStruct)
{
uint32_t row_n;
SYS->CLKEN |= (1 << SYS_CLKEN_SDRAM_Pos);
SYS->CLKDIV &= ~SYS_CLKDIV_SDRAM_Msk;
SYS->CLKDIV |= (1 << SYS_CLKDIV_SDRAM_Pos); //2分频
SDRAMC->CR0 = (2 << SDRAMC_CR0_BURSTLEN_Pos) | //2 Burst Length为4
(initStruct->CASLatency << SDRAMC_CR0_CASDELAY_Pos);
SDRAMC->CR1 = (initStruct->CellSize << SDRAMC_CR1_CELLSIZE_Pos) |
(initStruct->CellWidth << SDRAMC_CR1_CELL32BIT_Pos) |
(initStruct->CellBank << SDRAMC_CR1_BANK_Pos) |
(0 << SDRAMC_CR1_32BIT_Pos) |
(initStruct->TimeTMRD << SDRAMC_CR1_TMRD_Pos) |
(initStruct->TimeTRRD << SDRAMC_CR1_TRRD_Pos) |
(initStruct->TimeTRAS << SDRAMC_CR1_TRAS_Pos) |
(initStruct->TimeTRC << SDRAMC_CR1_TRC_Pos) |
(initStruct->TimeTRCD << SDRAMC_CR1_TRCD_Pos) |
(initStruct->TimeTRP << SDRAMC_CR1_TRP_Pos);
SDRAMC->LATCH = 0x02;
switch (initStruct->CellSize)
{
case SDRAM_CELLSIZE_16Mb:
row_n = 11;
break;
case SDRAM_CELLSIZE_64Mb:
row_n = 12;
break;
case SDRAM_CELLSIZE_128Mb:
row_n = 12;
break;
case SDRAM_CELLSIZE_256Mb:
row_n = 13;
break;
default:
row_n = 13;
break;
}
SDRAMC->REFRESH = (1 << SDRAMC_REFRESH_EN_Pos) |
(((SystemCoreClock / 2) / 1000 * 64 / (1 << row_n)) << SDRAMC_REFRESH_RATE_Pos);
while (SDRAMC->REFDONE == 0)
;
}
/******************************************************************************************************************************************
* 函数名称: SDRAM_Enable()
* 功能说明: SDRAM使能使能后可读写SDRAM
* 输 入: 无
* 输 出: 无
* 注意事项: 无
******************************************************************************************************************************************/
void SDRAM_Enable(void)
{
uint32_t i;
SYS->CLKEN |= (1 << SYS_CLKEN_SDRAM_Pos);
SDRAMC->REFRESH |= (1 << SDRAMC_REFRESH_EN_Pos);
for (i = 0; i < 100; i++)
__NOP();
}
/******************************************************************************************************************************************
* 函数名称: SDRAM_Disable()
* 功能说明: SDRAM禁能禁能后SDRAM颗粒进入低功耗模式、并自刷新不可读写
* 输 入: 无
* 输 出: 无
* 注意事项: 无
******************************************************************************************************************************************/
void SDRAM_Disable(void)
{
uint32_t i;
SYS->CLKEN |= (1 << SYS_CLKEN_SDRAM_Pos);
SDRAMC->REFRESH &= ~(1 << SDRAMC_REFRESH_EN_Pos);
for (i = 0; i < 100; i++)
__NOP();
}