/****************************************************************************************************************************************** 
* 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)
{
	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
				  (2 << SDRAMC_CR0_CASDELAY_Pos);
	
	SDRAMC->CR1 = (initStruct->CellSize << SDRAMC_CR1_CELLSIZE_Pos) |
				  (initStruct->CellWidth << SDRAMC_CR1_CELL32BIT_Pos) |
				  (initStruct->CellBank << SDRAMC_CR1_BANK_Pos) |
				  (initStruct->DataWidth << 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;
	
	SDRAMC->REFRESH = (1 << SDRAMC_REFRESH_EN_Pos) |
					  (0x0FA << SDRAMC_REFRESH_RATE_Pos);
	
    while(SDRAMC->REFDONE == 0);
}
