ks0066.c

/**
	ks0066.c - Working with LCD displays on based controllers KS0066 
	
	Author:	Vitaliy Zhuk
 */

#include <util/delay.h>
#include "ks0066.h"

void lcdInit()
{
	#ifdef KS0066_4BIT
		uint8_t command = (1 << 5) | (0 << 4) | (KS0066_COUNT_LINES << 3) | (KS0066_CHAR_SIZE << 2);
	#else
		uint8_t command = (1 << 5) | (1 << 4) | (KS0066_COUNT_LINES << 3) | (KS0066_CHAR_SIZE << 2);
	#endif
	
	lcdWriteByte(command, 1);
}

void lcdWriteByte(uint8_t byte, uint8_t command)
{
	// Configure ports for writing data
	#ifndef KS0066_4BIT
		KS0066_DATA_DDR = 0xFF;
		KS0066_DATA_PORT = 0x00;
	#else
		#if KS0066_4BIT_HIGH_BYTE == 1
			KS0066_DATA_DDR |= 0b11110000;
			KS0066_DATA_PORT &= ~(0b11110000);
		#else
			KS0066_DATA_DDR |= 0b00001111;
			KS0066_DATA_PORT &= ~(0b00001111);
		#endif
	#endif
	
	KS0066_CTRL_DDR |= (1 << KS0066_CTRL_STROBE_PIN) | (1 << KS0066_CTRL_RW_PIN) | (1 << KS0066_CTRL_RS_PIN);
	
	// Set the flag for writing (Command/Data)
	if (command) {
		KS0066_WRITE_COMMAND();
	} else {
		KS0066_WRITE_DATA();
	}
	
	// Write data, not reading
	KS0066_WRITE();
	
	#ifdef KS0066_4BIT
		// 4 BIT mode
		#if KS0066_4BIT_HIGH_BYTE == 1
			uint8_t clearByte = 0b11110000;
			uint8_t highByte = byte & 0b11110000;
			uint8_t lowByte = byte << 4;
		#else
			uint8_t clearByte = 0b00001111;
			uint8_t highByte = byte >> 4;
			uint8_t lowByte = byte & 0b00001111;
		#endif
		
		KS0066_DATA_PORT &= ~clearByte;
		KS0066_DATA_PORT |= highByte;
		KS0066_STROBE_SET();
		_delay_us(2);
		KS0066_STROBE_RESET();
		
		KS0066_DATA_PORT &= ~clearByte;
		KS0066_DATA_PORT |= lowByte;
 		KS0066_STROBE_SET();
 		_delay_us(2);
 		KS0066_STROBE_RESET();
	#else 
		// 8 BIT mode
		KS0066_DATA_PORT = byte;
		KS0066_STROBE_SET();
		_delay_us(2);
		KS0066_STROBE_RESET();
	#endif
	
	// Secondary delay for process command/data
	// For command with DRAM, timeout must be a large than 1.52 ms (1520 us),
	// and for another command, timeout must be a large than 37 us (0.000037 s).
	if (command) {
		// This is a command register. Check command
		if (byte == KS0066_CMD_CLEAR || byte == KS0066_CMD_GOTO_HOME) {
			// This is clear display or goto home command. Timeout >= 1.52ms
			_delay_us(1520);
		} else {
			_delay_us(37);
		}
	} else {
		_delay_us(37);
	}
}

void lcdWriteCommand(uint8_t command)
{
	lcdWriteByte(command, 1);
}

void lcdWriteData(uint8_t data)
{
	lcdWriteByte(data, 0);
}
 
void lcdPuts(const char *buffer)
{
	while (*buffer) {
		lcdWriteByte(*buffer, 0);
		buffer++;
	}
}

void lcdGoto(uint8_t byte, uint8_t line)
{
	uint8_t command = (1 << 7);
	
	if (line == 1) {
		// First list
		byte += 40;
	}
	
	command += byte;
	
	lcdWriteByte(command, 1);
}

void lcdShift(uint8_t mode, uint8_t to)
{
	uint8_t command = (1 << 4) | (mode << 3) | (to << 2);
	lcdWriteByte(command, 1);
}

ks0066.h

/**
	ks0066.h - Working with LCD displays on based controllers KS0066 
	
	Author:	Vitaliy Zhuk
 */
 
#ifndef __KS0066_H_
#define __KS0066_H_ 1
 
// Data PORT/DDR must be defined
#ifndef KS0066_DATA_DDR
# error "KS0066_DATA_DDR not defined for lcd/ks0066.h"
#endif
 
#ifndef KS0066_DATA_PORT
# error "KS0066_DATA_PORT not defined for lcd/ks0066.h"
#endif
 
// Controls PORT/DDR must be defined
#ifndef KS0066_CTRL_DDR
# error "KS0066_CTRL_DDR not defined for lcd/ks0066.h"
#endif
 
#ifndef KS0066_CTRL_PORT
# error "KS0066_CTRL_PORT not defined for lcd/ks0066.h"
#endif

#ifndef KS0066_CTRL_STROBE_PIN
# error "KS0066_CTRL_STROBE_PIN not defined for lcd/ks0066.h"
#endif

#ifndef KS0066_CTRL_RS_PIN
# error "KS0066_CTRL_RS_PIN not defined for lcd/ks0066.h"
#endif

#ifndef KS0066_CTRL_RW_PIN
# error "KS0066_CTRL_RS_PIN not defined for lcd/ks0066.h"
#endif

// Mode constants
#ifdef KS0066_4BIT
#ifndef KS0066_4BIT_HIGH_BYTE
#define KS0066_4BIT_HIGH_BYTE 1
#endif
#endif

#ifndef KS0066_COUNT_LINES
#define KS0066_COUNT_LINES 1
#endif

#ifndef KS0066_CHAR_SIZE
#define KS0066_CHAR_SIZE 0
#endif

// Define commands
#define KS0066_CMD_CLEAR 0x01
#define KS0066_CMD_GOTO_HOME 0x02
#define KS0066_CMD_CURSOR_SHIFT_LEFT 0x04
#define KS0066_CMD_CURSOR_SHIFT_RIGHT 0x06
#define KS0066_CMD_DISPLAY_OFF 0x08
#define KS0066_CMD_CURSOR_OFF 0x0C
#define KS0066_CMD_CURSOR_RECTANGLE 0x0D
#define KS0066_CMD_CURSOR_LINE 0x0E

// Define macros
#define KS0066_STROBE_SET() KS0066_CTRL_PORT |= (1 << KS0066_CTRL_STROBE_PIN)
#define KS0066_STROBE_RESET() KS0066_CTRL_PORT &= ~(1 << KS0066_CTRL_STROBE_PIN)
 
#define KS0066_WRITE() KS0066_CTRL_PORT &= ~(1 << KS0066_CTRL_RW_PIN)
#define KS0066_READ() KS0066_CTRL_PORT |= (1 << KS0066_CTRL_RW_PIN)
 
#define KS0066_WRITE_COMMAND() KS0066_CTRL_PORT &= ~(1 << KS0066_CTRL_RS_PIN)
#define KS0066_WRITE_DATA() KS0066_CTRL_PORT |= (1 << KS0066_CTRL_RS_PIN)

/**
	Initialize of LCD. Send first command for configure
	mode, count lines and char size
 */
void lcdInit();

/**
	Write the byte \a byte to LCD as command, if \a command is 1 
	or as data, if \a command is 0
 */
void lcdWriteByte(uint8_t byte, uint8_t command);

/**
	Write command \a command to LCD
 */
void lcdWriteCommand(uint8_t command);

/**
	Write data \a data to LCD
 */
void lcdWriteData(uint8_t data);
 
/**
	Write bytes \a *buffer as command, if \a command is 1
	or as data, if \a command is 0
 */
void lcdPuts(const char *buffer);

/**
	Goto position if LCD, to char \a byte, and line \a line.
	
	\note The indicate byte and line start from 0 (zero).
 */
void lcdGoto(uint8_t byte, uint8_t line);

/**
	LCD shift. Shift cursor or display
	If \a mode is 1, then shift display, else shift cursor
	If \a to is 1, then shift to right, else shift to left
 */
void lcdShift(uint8_t mode, uint8_t to);

#endif /* __KS0066_H_ */

main.c

/**
 * Used on Atmega 8535
 *
 * Use one port: PORTA 0-6
 */
#define F_CPU 1000000 // 1 Mhz

#define KS0066_DATA_DDR DDRA
#define KS0066_DATA_PORT PORTA
#define KS0066_CTRL_DDR DDRA
#define KS0066_CTRL_PORT PORTA
#define KS0066_CTRL_STROBE_PIN PINA6
#define KS0066_CTRL_RW_PIN PINA5
#define KS0066_CTRL_RS_PIN PINA4
#define KS0066_4BIT 1
#define KS0066_4BIT_HIGH_BYTE 0

#include <stdio.h>
#include <avr/io.h>
#include <util/delay.h>
#include "lcd/ks0066.c"

int main(void)
{	
	_delay_ms(100);
	
	// Initialize LCD
	lcdInit();
	lcdWriteCommand(KS0066_CMD_CLEAR);
	lcdWriteCommand(KS0066_CMD_CURSOR_OFF);
	
	// Write data
	lcdGoto(0, 0);
	lcdPuts("Hi... LCD");
	
	lcdGoto(0, 1);
	lcdPuts("This work :D");
	
    while(1)
    {
    }
}