Inital commit

.gitignore

@@ -32,3 +32,5 @@
 *.out
 *.app
 
+bin/*
+.vscode/*

README.md

@@ -1,2 +1,6 @@
-# lcd
+# AVR LCD Library
+
+Original source
+
+https://www.electronicwings.com/avr-atmega/interfacing-lcd-16x2-in-4-bit-mode-with-atmega-16-32-
 

lcd.cpp

@@ -0,0 +1,68 @@
+#include <util/delay.h>
+#include "lcd.h"
+
+namespace lcd {
+    void command(unsigned char cmnd) {
+        LCD_Port = (LCD_Port & 0x0F) | (cmnd & 0xF0); /* sending upper nibble */
+        LCD_Port &= ~ (1<<LCD_RS);		/* LCD_RS=0, command reg. */
+        LCD_Port |= (1<<LCD_EN);		/* Enable pulse */
+        _delay_us(1);
+        LCD_Port &= ~ (1<<LCD_EN);
+
+        _delay_us(200);
+
+        LCD_Port = (LCD_Port & 0x0F) | (cmnd << 4);  /* sending lower nibble */
+        LCD_Port |= (1<<LCD_EN);
+        _delay_us(1);
+        LCD_Port &= ~ (1<<LCD_EN);
+        _delay_ms(2);
+    }
+
+    void put(unsigned char data) {
+        LCD_Port = (LCD_Port & 0x0F) | (data & 0xF0); /* sending upper nibble */
+        LCD_Port |= (1<<LCD_RS);		/* LCD_RS=1, data reg. */
+        LCD_Port|= (1<<LCD_EN);
+        _delay_us(1);
+        LCD_Port &= ~ (1<<LCD_EN);
+        _delay_us(200);
+
+        LCD_Port = (LCD_Port & 0x0F) | (data << 4); /* sending lower nibble */
+        LCD_Port |= (1<<LCD_EN);
+        _delay_us(1);
+        LCD_Port &= ~ (1<<LCD_EN);
+        _delay_ms(2);
+    }
+
+    void init(void) {
+        LCD_DDR = (1<<LCD_EN)|(1<<LCD_RS)|0xF0;			/* Make LCD port direction as o/p */
+        _delay_ms(20);			/* LCD Power ON delay always >15ms */
+        command(0x02);		/* send for 4 bit initialization of LCD  */
+        command(0x28);              /* 2 line, 5*7 matrix in 4-bit mode */
+        command(0x0c);              /* Display on cursor off*/
+        command(0x06);              /* Increment cursor (shift cursor to right)*/
+        command(0x01);              /* Clear display screen*/
+        _delay_ms(2);
+    }
+
+
+    void string (char *str) {
+        int i;
+        for(i=0;str[i]!=0;i++) {		/* Send each char of string till the NULL */
+            put(str[i]);
+        }
+    }
+
+    void string_xy (char row, char pos, char *str) {
+        if (row == 0 && pos<16)
+            command((pos & 0x0F)|0x80);	/* Command of first row and required position<16 */
+        else if (row == 1 && pos<16)
+            command((pos & 0x0F)|0xC0);	/* Command of first row and required position<16 */
+        string(str);		/* Call LCD string function */
+    }
+
+    void clear() {
+        command (0x01);		/* Clear display */
+        _delay_ms(2);
+        command (0x80);		/* Cursor at home position */
+    }
+} // namespace lcd

lcd.h

@@ -0,0 +1,22 @@
+#pragma once
+#include <avr/io.h>
+
+
+#define LCD_Dir  DDRA			/* Define LCD data port direction */
+#define LCD_DDR  DDRA			/* Define LCD data port direction */
+#define LCD_Port PORTA			/* Define LCD data port */
+#define LCD_Port PORTA			/* Define LCD data port */
+#define LCD_RS PA2				/* Define Register Select pin */
+#define LCD_EN PA3 				/* Define Enable signal pin */
+ 
+
+namespace lcd {
+    void command(unsigned char cmnd);
+    void put(unsigned char data);
+    void init();
+    void string(char *str);
+    void string_xy (char row, char pos, char *str);
+    void clear();	
+
+    
+} // namespace lcd

main.cpp

@@ -0,0 +1,18 @@
+#define F_CPU 8000000UL			/* Define CPU Frequency e.g. here 8MHz */
+#include <avr/io.h>			/* Include AVR std. library file */
+#include <util/delay.h>			/* Include Delay header file */
+#include "lcd.h"
+
+
+
+ 
+int main()
+{
+
+	lcd::init();			/* Initialization of LCD*/
+
+	lcd::string("CVR");	/* Write string on 1st line of LCD*/
+	lcd::command(0xC0);		/* Go to 2nd line*/
+	lcd::string("Hello World");	/* Write string on 2nd line*/
+	while(1);
+}

makefile

@@ -0,0 +1,21 @@
+MCU=atmega32
+F_CPU=8000000
+PROG=dragon_jtag
+CC=avr-g++
+OBJCOPY=avr-objcopy
+CFLAGS=-Wall -g -mmcu=${MCU} -DF_CPU=${F_CPU} -I.
+TARGET=main
+SRCS=*.cpp
+
+default: build flash
+
+build:
+	${CC} ${CFLAGS} -o bin/${TARGET}.bin  ${SRCS}
+	#${CC} ${CFLAGS} -o bin/${TARGET}.elf  ${SRCS}
+	${OBJCOPY} -j .text -j .data -O ihex bin/${TARGET}.bin bin/${TARGET}.hex
+
+flash:
+	avrdude -p ${MCU} -c ${PROG} -U flash:w:bin/main.hex
+
+clean:
+	rm -f bin/*