基于atmega8的lcd1602液晶四线驱动程序

#include <avr/io.h> #include "lcd1602.h" #include <util/delay.h> #include <avr/eeprom.h> // sendet ein Datenbyte an das LCD void lcd_data(unsigned char temp1){ LCD_RS_PORT |= (1<<LCD_RS); // RS auf 1 setzen PC3置1,选择数据寄存器 lcd_send(temp1); } // sendet einen Befehl an das LCD void lcd_command(unsigned char temp1){ //pc3,高电平数据寄存器,低电平指令寄存器 LCD_RS_PORT &= ~(1<<LCD_RS); // RS auf 0 setzen PC3置0,选择指令寄存器 lcd_send(temp1); } //4-Bit-Modus void lcd_send(unsigned char data) { // 先高位 //LCD_DATA_PORT = (LCD_DATA_PORT & 0xF0) | ((data >> 4) & 0x0F); LCD_DATA_PORT = (LCD_DATA_PORT & ~(LCD_DATA_MARK)) | ((data >> LCD_DATA_SHIFT) & LCD_DATA_MARK); _delay_us(500); lcd_enable(); // 后低位 //LCD_DATA_PORT = (LCD_DATA_PORT & 0xF0) | (data & 0x0F); LCD_DATA_PORT = (LCD_DATA_PORT & ~(LCD_DATA_MARK)) | ((data << LCD_DATA_SHIFT) & LCD_DATA_MARK); _delay_us(500); lcd_enable(); _delay_us(200); LCD_DATA_PORT &= ~(LCD_DATA_MARK); } // Enable-Puls void lcd_enable(void){ LCD_EN_PORT |= (1<<LCD_EN); //PD5置1,执行指令 _delay_us(10); LCD_EN_PORT &= ~(1<<LCD_EN); //PD5置0 } void lcd_init(void){ // Port auf Ausgang schalten //LCD_DDR = LCD_DDR | 0x0F | (1<<LCD_RS) | (1<<LCD_EN1); _delay_ms(100); LCD_DATA_DDR |= LCD_DATA_MARK; //设置DATA线的方向为输出 LCD_RS_DDR |= (1<<LCD_RS); //PC3方向寄存器置1,方向为输出.如果PC3置1,第四脚,高电平数据寄存器,低电平指令寄存器 LCD_EN_DDR |= (1<<LCD_EN); //PD5方向寄存器置1,方向为输出.PD5置1,使能端置1,可以执行指令 // muss 3mal hintereinander gesendet werden zur Initialisierung _delay_ms(50); //LCD_DATA_PORT = (LCD_DATA_PORT & 0xF0 & ~(1<<LCD_RS)) | 0x03; LCD_RS_PORT &= ~(1<<LCD_RS); //PC3置0,选择指令寄存器 LCD_DATA_PORT = (LCD_DATA_PORT & ~(LCD_DATA_MARK)) | (0x03<<2); //四线高两位置0,低两位置1 lcd_enable(); _delay_ms(6); LCD_DATA_PORT = (LCD_DATA_PORT & ~(LCD_DATA_MARK)) | (0x03<<2); lcd_enable(); _delay_ms(1); LCD_DATA_PORT = (LCD_DATA_PORT & ~(LCD_DATA_MARK)) | (0x03<<2); lcd_enable(); _delay_ms(1); //LCD_DATA_PORT = (LCD_DATA_PORT & 0xF0 & ~(1<<LCD_RS)) | 0x02; LCD_RS_PORT &= ~(1<<LCD_RS); //PC3置0,选择指令寄存器 LCD_DATA_PORT = (LCD_DATA_PORT & ~(LCD_DATA_MARK)) | (0x02<<2); //四线高两位置0,第三位置1,末位置0 _delay_ms(1); lcd_enable(); _delay_ms(10); /* 4-bit interface, dual line, 5x7 dots */ lcd_command(LCD_FUNCTION_4BIT_2LINES); /* display on, cursor off */ lcd_command(LCD_DISP_ON); /* display shift off, inc cursor move dir 模式为光标右移,字符不移 */ lcd_command(LCD_ENTRY_INC_); lcd_clear(); _delay_ms(20); } void lcd_clear(void){ lcd_command(CLEAR_DISPLAY); _delay_ms(30); //此处的30 经验证为最小值，原值为5 } void lcd_string(char *data){ while(*data) { lcd_data(*data); data++; } }