本文实现DMA快速显示文字
汉字点阵通常是16*16点阵,那么用DMA一次性显示汉字,应该至少申请480*16个字节的空间,用于显示一行文字,其中480是屏幕一行用DMA驱动所需内存。
一、 源码
HX8347.h
#ifndef USER_HX8347_H_
#define USER_HX8347_H_#define SPI_hardware
#define SPI_hardware_dma#define Buf_Size 480*16#define X_MAX_PIXEL 240
#define Y_MAX_PIXEL 320#define RED 0xf800
#define GREEN 0x07e0
#define BLUE 0x001f
#define WHITE 0xffff
#define BLACK 0x0000
#define YELLOW 0xFFE0
#define GRAY0 0xEF7D //灰色0 3165 00110 001011 00101
#define GRAY1 0x8410 //灰色1 00000 000000 00000
#define GRAY2 0x4208 //灰色2 1111111111011111#ifdef SPI_hardware#define LCD_CS GPIO_Pin_0 // CS:PA0#define LCD_SDA GPIO_Pin_7 // SDA:PA7 SPI1 //硬件SPI实现,不用人工处理#define LCD_SCL GPIO_Pin_5 // SCL:PA5 SPI1 //硬件SPI实现,不用人工处理#define LCD_RST GPIO_Pin_4 // RST:PA4
#else#define LCD_CS GPIO_Pin_0 // CS:PA0#define LCD_SDA GPIO_Pin_1 // SDA:PA1#define LCD_SCL GPIO_Pin_3 // SCL:PA3#define LCD_RST GPIO_Pin_4 // RST:PA4
#endif#define LCD_SCL_SET GPIO_WriteBit(GPIOA, LCD_SCL,Bit_SET)
#define LCD_SDA_SET GPIO_WriteBit(GPIOA, LCD_SDA,Bit_SET)
#define LCD_CS_SET GPIO_WriteBit(GPIOA, LCD_CS,Bit_SET)
#define LCD_RST_SET GPIO_WriteBit(GPIOA, LCD_RST,Bit_SET)#define LCD_SCL_CLR GPIO_WriteBit(GPIOA, LCD_SCL,Bit_RESET)
#define LCD_SDA_CLR GPIO_WriteBit(GPIOA, LCD_SDA,Bit_RESET)
#define LCD_CS_CLR GPIO_WriteBit(GPIOA, LCD_CS,Bit_RESET)
#define LCD_RST_CLR GPIO_WriteBit(GPIOA, LCD_RST,Bit_RESET)void LCD_GPIO_Init(void);
void Lcd_WriteIndex(unsigned char Index);
void Lcd_WriteData(unsigned char Data);
void LCD_WriteData_16Bit(unsigned int Data);
void Lcd_Write_REG(unsigned char Index,unsigned char Data);
void LCD_Init(void);
void Lcd_Clear(unsigned int Color);
void FillRect(u16 x1, u16 y1, u16 x2, u16 y2, u16 color);
void FillRect_DMA(u16 color);void Gui_DrawFont_GBK16(unsigned int x, unsigned int y, unsigned int fc, unsigned int bc, unsigned char *s);
void Gui_DrawFont_GBK16_DMA(unsigned int x, unsigned int y, unsigned int fc, unsigned int bc,unsigned char *s);#endif /* USER_HX8347_H_ */
HX8347.c
#include "debug.h"
#include "HX8347.h"
#include "font.h"extern unsigned char TxData[];
extern void MYDMA_Enable(DMA_Channel_TypeDef*DMA_CHx);void LCD_GPIO_Init(void)
{GPIO_InitTypeDef GPIO_InitStructure = {0};RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
#ifdef SPI_hardwareGPIO_InitStructure.GPIO_Pin = LCD_CS|LCD_RST;
#elseGPIO_InitStructure.GPIO_Pin = LCD_SCL|LCD_SDA|LCD_CS|LCD_RST;
#endifGPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init(GPIOA, &GPIO_InitStructure);
}//向SPI总线传输一个8位数据void SPI_WriteData(unsigned char Data)
{
#ifdef SPI_hardwareSPI_I2S_SendData( SPI1, Data);while( SPI_I2S_GetFlagStatus( SPI1, SPI_I2S_FLAG_TXE ) == RESET );//Delay_Us(1);uint32_t i;SysTick->SR &= ~(1 << 0);i = 8;SysTick->CMP = i;SysTick->CTLR |= (1 << 4);SysTick->CTLR |= (1 << 5) | (1 << 0);while((SysTick->SR & (1 << 0)) != (1 << 0));SysTick->CTLR &= ~(1 << 0);#elseunsigned char i=0;for(i=8;i>0;i--){if(Data&0x80)LCD_SDA_SET; //输出数据else LCD_SDA_CLR;LCD_SCL_CLR;LCD_SCL_SET;Data<<=1;}
#endif
}//向液晶屏写一个8位指令void Lcd_WriteIndex(unsigned char Index)
{//SPI 写命令时序开始LCD_CS_CLR;SPI_WriteData(0x70);SPI_WriteData(Index);LCD_CS_SET;
}//向液晶屏写一个8位数据void Lcd_WriteData(unsigned char Data)
{LCD_CS_CLR;SPI_WriteData(0x72);SPI_WriteData(Data);LCD_CS_SET;
}//向液晶屏写一个16位数据
void LCD_WriteData_16Bit(unsigned int Data)
{LCD_CS_CLR;SPI_WriteData(0x72);SPI_WriteData(Data>>8);SPI_WriteData(Data);LCD_CS_SET;
}void Lcd_Write_REG(unsigned char Index,unsigned char Data)
{Lcd_WriteIndex(Index);Lcd_WriteData(Data);
}void Lcd_Reset(void)
{LCD_RST_CLR;Delay_Ms(50);LCD_RST_SET;Delay_Ms(50);
}// set region to paint
void LCD_SetWindow(unsigned int x1,unsigned int y1,unsigned int x2,unsigned int y2)
{//SCLcd_Write_REG(0x02,x1>>8); // Column address start2Lcd_Write_REG(0x03,(u8)x1); // Column address start1//ECLcd_Write_REG(0x04,x2>>8); // Column address end2Lcd_Write_REG(0x05,(u8)x2); // Column address end1//SPLcd_Write_REG(0x06,y1>>8); // Row address start2Lcd_Write_REG(0x07,(u8)y1); // Row address start1//EPLcd_Write_REG(0x08,y2>>8); // Row address end2Lcd_Write_REG(0x09,(u8)y2); // Row address end1//写0x22到index register,那么下次send data就会直接被写到graphic ramLcd_WriteIndex(0x22);
}void FillRect(u16 x1, u16 y1, u16 x2, u16 y2, u16 color)
{LCD_SetWindow(x1, y1,x2,y2);x2 = x2 - x1 + 1;y2 = y2 - y1 + 1;LCD_CS_CLR;SPI_WriteData(0x72);for(x1 = x2; x1 != 0 ; x1--){for (y1 = y2;y1 != 0 ;y1--){SPI_WriteData(color>>8);SPI_WriteData(color);}}LCD_CS_SET;
}void FillRect_DMA(u16 color)
{int16_t j;LCD_SetWindow(0, 0,239,319);LCD_CS_CLR;SPI_WriteData(0x72);for(j=0 ;j<Buf_Size;){TxData[j] = color>>8;TxData[j+1] = color;j += 2;}for(j = 0 ; j<320/(Buf_Size/480) ; j++){SPI_I2S_DMACmd(SPI1,SPI_I2S_DMAReq_Tx,ENABLE);MYDMA_Enable(DMA1_Channel3);while(1){if(DMA_GetFlagStatus(DMA1_FLAG_TC3)!=RESET){DMA_ClearFlag(DMA1_FLAG_TC3);break;}}}LCD_CS_SET;
}void LCD_Init(void)
{//LCD_GPIO_Init();Lcd_Reset();Lcd_Write_REG(0x18,0x88); //UADJ 75HzLcd_Write_REG(0x19,0x01); //OSC_EN='1', start Osc//Power Voltage SettingLcd_Write_REG(0x1B,0x1e); //VRH=4.60V 0x1eLcd_Write_REG(0x1C,0x04); //AP Crosstalk 04Lcd_Write_REG(0x1A,0x01); //BT (VGH~15V,VGL~-10V,DDVDH~5V) 0x01Lcd_Write_REG(0x24,0x21); //VMH 27 0x38Lcd_Write_REG(0x25,0x5F); //VML//VCOM offsetLcd_Write_REG(0x23,0x8C); //for Flicker adjustLcd_Write_REG(0x1F,0x88);// GAS=1, VOMG=00, PON=0, DK=1, XDK=0, DVDH_TRI=0, STB=0Delay_Ms(50);Lcd_Write_REG(0x1F,0x80);// GAS=1, VOMG=00, PON=0, DK=0, XDK=0, DVDH_TRI=0, STB=0Delay_Ms(50);Lcd_Write_REG(0x1F,0x90);// GAS=1, VOMG=00, PON=1, DK=0, XDK=0, DVDH_TRI=0, STB=0Delay_Ms(50);Lcd_Write_REG(0x1F,0xD0);// GAS=1, VOMG=10, PON=1, DK=0, XDK=0, DDVDH_TRI=0, STB=0Delay_Ms(50);//Display ON SettingLcd_Write_REG(0x28,0x38); //GON=1, DTE=1, D=1000Delay_Ms(50);Lcd_Write_REG(0x28,0x3C); //GON=1, DTE=1, D=1100Lcd_Write_REG(0x36,0x09); //REV, BGRLcd_Write_REG(0x17,0x05); //16BIT/PIXEL//Gamma 2.2 SettingLcd_Write_REG(0x40,0x00); //Lcd_Write_REG(0x41,0x00); //Lcd_Write_REG(0x42,0x00); //Lcd_Write_REG(0x43,0x11); //Lcd_Write_REG(0x44,0x0e); //Lcd_Write_REG(0x45,0x23); //Lcd_Write_REG(0x46,0x08); //Lcd_Write_REG(0x47,0x53); //Lcd_Write_REG(0x48,0x03); //Lcd_Write_REG(0x49,0x11); //Lcd_Write_REG(0x4A,0x18); //Lcd_Write_REG(0x4B,0x1a); //Lcd_Write_REG(0x4C,0x16); //Lcd_Write_REG(0x50,0x1c); //Lcd_Write_REG(0x51,0x31); //Lcd_Write_REG(0x52,0x2e); //Lcd_Write_REG(0x53,0x3f); //Lcd_Write_REG(0x54,0x3f); //Lcd_Write_REG(0x55,0x3f); //Lcd_Write_REG(0x56,0x2c); //Lcd_Write_REG(0x57,0x77); //Lcd_Write_REG(0x58,0x09); //Lcd_Write_REG(0x59,0x05); //Lcd_Write_REG(0x5A,0x07); //Lcd_Write_REG(0x5B,0x0e); //Lcd_Write_REG(0x5C,0x1c); //Lcd_Write_REG(0x5D,0x88); //Delay_Ms(100);FillRect(0, 0, 239, 319, RED );
}/*************************************************
函数名:LCD_DrawPoint
功能:画一个点
入口参数:无
返回值:无
*************************************************/
void Gui_DrawPoint(unsigned int x,unsigned int y,unsigned int Data)
{LCD_SetWindow(x,y,x+1,y+1);LCD_WriteData_16Bit(Data);
}void Gui_DrawPoint_DMA(unsigned int x,unsigned int y,unsigned int Data)
{//LCD_SetWindow(x,y,x+1,y+1);//LCD_WriteData_16Bit(Data);TxData[2*x+y*480]=Data>>8;TxData[2*x+y*480+1]=Data;}void DMA_BUFFER_RESET(unsigned int bc)
{unsigned int j;for(j=0 ;j<Buf_Size;){TxData[j] = bc>>8;TxData[j+1] = bc;j += 2;}
}void Gui_DrawFont_GBK16(unsigned int x, unsigned int y, unsigned int fc, unsigned int bc,unsigned char *s)
{unsigned char i,j;unsigned short k,x0;x0=x;while(*s){if((*s) < 128){k=*s;if (k==13){x=x0;y+=16;}else{if (k>32) k-=32; else k=0;for(i=0;i<16;i++)for(j=0;j<8;j++){if(asc16[k*16+i]&(0x80>>j)) Gui_DrawPoint(x+j,y+i,fc);else{if (fc!=bc) Gui_DrawPoint(x+j,y+i,bc);}}x+=8;}s++;}else{for (k=0;k<hz16_num;k++){if ((hz16[k].Index[0]==*(s))&&(hz16[k].Index[1]==*(s+1))){for(i=0;i<16;i++){for(j=0;j<8;j++){if(hz16[k].Msk[i*2]&(0x80>>j)) Gui_DrawPoint(x+j,y+i,fc);else {if (fc!=bc) Gui_DrawPoint(x+j,y+i,bc);}}for(j=0;j<8;j++){if(hz16[k].Msk[i*2+1]&(0x80>>j)) Gui_DrawPoint(x+j+8,y+i,fc);else{if (fc!=bc) Gui_DrawPoint(x+j+8,y+i,bc);}}}}}s+=2;x+=16;}}
}void Gui_DrawFont_GBK16_DMA(unsigned int x, unsigned int y, unsigned int fc, unsigned int bc,unsigned char *s)
{unsigned char i,j;unsigned short k,x0,y0;x0=x;y0=y;x=0;y=0;DMA_BUFFER_RESET(bc); //清缓存while(*s){if((*s) < 128){k=*s;if (k==13){x=x0;y+=16;}else{if (k>32) k-=32; else k=0;for(i=0;i<16;i++)for(j=0;j<8;j++){if(asc16[k*16+i]&(0x80>>j)) Gui_DrawPoint_DMA(x+j,y+i,fc);else{if (fc!=bc) Gui_DrawPoint_DMA(x+j,y+i,bc);}}x+=8;}s++;}else{for (k=0;k<hz16_num;k++){if ((hz16[k].Index[0]==*(s))&&(hz16[k].Index[1]==*(s+1))){for(i=0;i<16;i++){for(j=0;j<8;j++){if(hz16[k].Msk[i*2]&(0x80>>j)) Gui_DrawPoint_DMA(x+j,y+i,fc);else {if (fc!=bc) Gui_DrawPoint_DMA(x+j,y+i,bc);}}for(j=0;j<8;j++){if(hz16[k].Msk[i*2+1]&(0x80>>j)) Gui_DrawPoint_DMA(x+j+8,y+i,fc);else{if (fc!=bc) Gui_DrawPoint_DMA(x+j+8,y+i,bc);}}}}}s+=2;x+=16;}}LCD_SetWindow(0,y0,239,y0+16);LCD_CS_CLR;SPI_WriteData(0x72);SPI_I2S_DMACmd(SPI1,SPI_I2S_DMAReq_Tx,ENABLE);MYDMA_Enable(DMA1_Channel3);while(1){if(DMA_GetFlagStatus(DMA1_FLAG_TC3)!=RESET){DMA_ClearFlag(DMA1_FLAG_TC3);break;}}LCD_CS_SET;}
main.c
/********************************** (C) COPYRIGHT *******************************
* File Name : main.c
* Author : WCH
* Version : V1.0.0
* Date : 2021/06/06
* Description : Main program body.
*********************************************************************************
* Copyright (c) 2021 Nanjing Qinheng Microelectronics Co., Ltd.
* Attention: This software (modified or not) and binary are used for
* microcontroller manufactured by Nanjing Qinheng Microelectronics.
*******************************************************************************//**@NoteGPIO routine:PA0 push-pull output.*/#include "debug.h"
#include "HX8347.h"/* Global define *//* Global Variable */unsigned char TxData[Buf_Size]={0};
u16 DMA1_MEM_LEN;/********************************************************************** @fn GPIO_Toggle_INIT** @brief Initializes GPIOA.0** @return none*/
void GPIO_Toggle_INIT(void)
{GPIO_InitTypeDef GPIO_InitStructure = {0};RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init(GPIOB, &GPIO_InitStructure);
}void SPI_1Lines_HalfDuplex_Init(void)
{GPIO_InitTypeDef GPIO_InitStructure={0};SPI_InitTypeDef SPI_InitStructure={0};RCC_APB2PeriphClockCmd( RCC_APB2Periph_SPI1|RCC_APB2Periph_GPIOA, ENABLE );GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init( GPIOA, &GPIO_InitStructure );GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init( GPIOA, &GPIO_InitStructure );SPI_InitStructure.SPI_Direction = SPI_Direction_1Line_Tx;SPI_InitStructure.SPI_Mode = SPI_Mode_Master;SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low; //在空闲状态下,时钟线保持高电平SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge; //数据在时钟的上升沿被传输。SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_4;SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;SPI_InitStructure.SPI_CRCPolynomial = 7;SPI_Init( SPI1, &SPI_InitStructure );SPI_Cmd( SPI1, ENABLE );
}//使能dma1的通道3,因为spi输出对应的是此通道
void MYDMA_Enable(DMA_Channel_TypeDef*DMA_CHx)
{DMA_Cmd(DMA_CHx, DISABLE );DMA_SetCurrDataCounter(DMA1_Channel3,DMA1_MEM_LEN);DMA_Cmd(DMA_CHx, ENABLE);
}/********************************************************************** @fn DMA_Tx_Init** @brief Initializes the DMAy Channelx configuration.** @param DMA_CHx - x can be 1 to 7.* ppadr - Peripheral base address.* memadr - Memory base address.* bufsize - DMA channel buffer size.** @return none*/
void DMA_Tx_Init( DMA_Channel_TypeDef* DMA_CHx, u32 ppadr, u32 memadr, u16 bufsize)
{DMA_InitTypeDef DMA_InitStructure={0};RCC_AHBPeriphClockCmd( RCC_AHBPeriph_DMA1, ENABLE );DMA_DeInit(DMA_CHx);DMA1_MEM_LEN=bufsize;DMA_InitStructure.DMA_PeripheralBaseAddr = ppadr;DMA_InitStructure.DMA_MemoryBaseAddr = memadr;DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;DMA_InitStructure.DMA_BufferSize = bufsize;DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;DMA_Init( DMA_CHx, &DMA_InitStructure );
}/********************************************************************** @fn main** @brief Main program.** @return none*/
int main(void)
{u8 i = 0;NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);SystemCoreClockUpdate();Delay_Init();USART_Printf_Init(115200); printf("SystemClk:%d\r\n", SystemCoreClock);printf( "ChipID:%08x\r\n", DBGMCU_GetCHIPID() );printf("GPIO Toggle TEST\r\n");GPIO_Toggle_INIT();LCD_GPIO_Init();
#ifdef SPI_hardwareprintf("SPI_HARDWARE");SPI_1Lines_HalfDuplex_Init();
#ifdef SPI_hardware_dmaprintf("SPI_HARDWARE_DMA");DMA_Tx_Init( DMA1_Channel3, (u32)&SPI1->DATAR, (u32)TxData, Buf_Size );DMA_Cmd( DMA1_Channel3, ENABLE );
#endif
#elseprintf("SPI_SOFTWARE");
#endifLCD_Init();GPIO_WriteBit(GPIOB, GPIO_Pin_13,Bit_RESET);while(1){Delay_Ms(1000);FillRect_DMA(GREEN);Gui_DrawFont_GBK16_DMA(0,5,BLACK,GREEN,"HELLO world");Gui_DrawFont_GBK16_DMA(0,25,RED,GREEN,"LCD OK DISPLAY");Gui_DrawFont_GBK16_DMA(0,45,RED,GREEN,"智能物联红外测温系统通过人数");Gui_DrawFont_GBK16_DMA(0,65,RED,GREEN,"报警人数人体温度环境表面距离");Gui_DrawFont_GBK16_DMA(0,85,RED,GREEN,"网络连接中.温度气象站雨量风速");Gui_DrawFont_GBK16_DMA(0,105,RED,GREEN,"创新实验平台℃");Delay_Ms(2000);FillRect_DMA(RED);Delay_Ms(1000);FillRect_DMA(BLUE);Gui_DrawFont_GBK16_DMA(0,5,WHITE,BLUE,"HELLO world");Gui_DrawFont_GBK16_DMA(0,25,WHITE,BLUE,"LCD OK DISPLAY");Gui_DrawFont_GBK16_DMA(0,45,WHITE,BLUE,"智能物联红外测温系统通过人数");Gui_DrawFont_GBK16_DMA(0,65,WHITE,BLUE,"报警人数人体温度环境表面距离");Gui_DrawFont_GBK16_DMA(0,85,WHITE,BLUE,"网络连接中.温度气象站雨量风速");Gui_DrawFont_GBK16_DMA(0,105,WHITE,BLUE,"创新实验平台℃");Delay_Ms(1000);FillRect_DMA(YELLOW);Delay_Ms(1000);FillRect(0, 0, 239, 63, RED );Gui_DrawFont_GBK16(15,5,BLACK,GRAY0,"HELLO world");Gui_DrawFont_GBK16(15,25,RED,GRAY0,"LCD OK DISPLAY");Gui_DrawFont_GBK16(15,45,RED,GRAY0,"智能物联红外测温系统通过人数");Gui_DrawFont_GBK16(15,65,RED,GRAY0,"报警人数人体温度环境表面距离");Gui_DrawFont_GBK16(15,85,RED,GRAY0,"网络连接中.温度气象站雨量风速");Gui_DrawFont_GBK16(15,105,RED,GRAY0,"创新实验平台℃");Delay_Ms(1000);GPIO_WriteBit(GPIOB, GPIO_Pin_13, (i == 0) ? (i = Bit_SET) : (i = Bit_RESET));printf( "GPIOB:%d\r\n", i);FillRect(0, 0, 239, 319, RED );Delay_Ms(1000);FillRect(0, 0, 239, 319, GREEN );Delay_Ms(1000);FillRect(0, 0, 239, 319, BLUE );FillRect(50, 50, 100, 100, RED );}
}
二、说明
1、增加了 Gui_DrawPoint_DMA(unsigned int x,unsigned int y,unsigned int Data)向DMA内存画点的功能
void Gui_DrawPoint_DMA(unsigned int x,unsigned int y,unsigned int Data)
{
TxData[2*x+y*480]=Data>>8;
TxData[2*x+y*480+1]=Data;}
2、增加了void DMA_BUFFER_RESET(unsigned int bc),用于清空DMA内存
void DMA_BUFFER_RESET(unsigned int bc)
{
unsigned int j;
for(j=0 ;j<Buf_Size;){
TxData[j] = bc>>8;
TxData[j+1] = bc;
j += 2;
}
}
3、增加了Gui_DrawFont_GBK16_DMA(unsigned int x, unsigned int y, unsigned int fc, unsigned int bc,unsigned char *s)。用于处理字符串并以DMA方式输出到屏幕。
void Gui_DrawFont_GBK16_DMA(unsigned int x, unsigned int y, unsigned int fc, unsigned int bc,unsigned char *s)
{
unsigned char i,j;
unsigned short k,x0,y0;
x0=x;
y0=y;
x=0;
y=0;DMA_BUFFER_RESET(bc); //清缓存
while(*s)
{if((*s) < 128)
{
k=*s;
if (k==13)
{
x=x0;
y+=16;
}
else
{
if (k>32) k-=32; else k=0;for(i=0;i<16;i++)
for(j=0;j<8;j++)
{
if(asc16[k*16+i]&(0x80>>j)) Gui_DrawPoint_DMA(x+j,y+i,fc);
else
{
if (fc!=bc) Gui_DrawPoint_DMA(x+j,y+i,bc);
}
}
x+=8;
}
s++;
}else
{
for (k=0;k<hz16_num;k++)
{
if ((hz16[k].Index[0]==*(s))&&(hz16[k].Index[1]==*(s+1)))
{for(i=0;i<16;i++)
{
for(j=0;j<8;j++)
{
if(hz16[k].Msk[i*2]&(0x80>>j)) Gui_DrawPoint_DMA(x+j,y+i,fc);
else {
if (fc!=bc) Gui_DrawPoint_DMA(x+j,y+i,bc);
}
}
for(j=0;j<8;j++)
{
if(hz16[k].Msk[i*2+1]&(0x80>>j)) Gui_DrawPoint_DMA(x+j+8,y+i,fc);
else
{
if (fc!=bc) Gui_DrawPoint_DMA(x+j+8,y+i,bc);
}
}
}
}
}
s+=2;x+=16;
}}
LCD_SetWindow(0,y0,239,y0+16);
LCD_CS_CLR;
SPI_WriteData(0x72);
SPI_I2S_DMACmd(SPI1,SPI_I2S_DMAReq_Tx,ENABLE);
MYDMA_Enable(DMA1_Channel3);while(1){
if(DMA_GetFlagStatus(DMA1_FLAG_TC3)!=RESET)
{
DMA_ClearFlag(DMA1_FLAG_TC3);
break;
}
}
LCD_CS_SET;}
三、总结
1、申请的DMA空间为480*16,对应于屏幕是一个240*16的长条空间。也就是每次向屏幕刷一个 240*16范围,对应文字就是一行。改变起始位置,就可以在其他地方再刷一行。
DMA快速显示文字