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LCD DMA day59

news 2025/8/22 10:53:56

十四：LCD 显示屏

一：基础概念

访问：

1.传输bank地址和行地址

2传输列地址及读写信号

3．写：写数据到DATA（先写到数据总线中，再数据操作）

读： (先数据操作，再从数据总线拿出数据)从DATA获取数据

二：代码

#include "lcd.h"
#include <s3c2440.h>void lcd0_init(void)
{//引脚GPCCON |= 0xffff;GPCCON = 0xaaaaaaaa;GPDUP  |= 0xffff;GPDCON = 0xaaaaaaaa;		//LCDCON1LCDCON1 |= (7 << 8) | (0x3 << 5) | (0xc << 1);//LCDCON2LCDCON2 |= (13 << 24) | (319 << 14);//LCDCON3LCDCON3 |= (80 << 19) | (239 << 8);//LCDCON5LCDCON5 |= (1 << 11) |(1 << 10) | (1 << 3);//LCDSADDRLCDSADDR1 | FRAMEBUFFER >> 1;LCDSADDR2 = (LCDSADDR1 & 0x1fffff) + 240*320;//最终使能LCDCON1 |= (0x1<< 0);
}void display_point(int x, int y, unsigned short col)
{*((unsigned short *)FRAMEBUFFER+y*240+x) = col;
}void clear(unsigned short col)
{int i = 0;int j = 0;for(i = 0; i < 320; i++)for(j = 0; j < 240; j++)display_point(j, i, col);
}-----------------------------------------------------clear(0xf800);display_point(120, 160, 0);display_point(125, 160, 0);display_point(120, 165, 0);display_point(125, 165, 0);

十五：DMA

从内存空间操作的，所以是AHB

#include "dma.h"
#include <s3c2440.h>void dma_init(void)
{DISRCC1 &= ~(0x3 << 0);	  	//AHB  增加DIDST1  &= ~(0x3 << 0);		//AHB  增加 DCON1 |= (1 << 31) | (1 << 30) | (1 << 27)| (1 << 22) | (0x2 << 20);DSTAT1 = 0;		
}
void memcpy(unsigned long * dest,unsigned long * src,int len)
{unsigned char i = 0;DISRC1 &= ~(0x3fffffff << 0);DISRC1 = (unsigned long)src;DIDST1 &= ~(0x3fffffff << 0);DIDST1 = (unsigned long)dest;DCON1 &= ~(0xfffff << 0);DCON1 |= (len << 0);DMASKTRIG1 |= (1 << 1) | (1 << 0);while((DSTAT1 & (1 << 20)));
}