LCD.c

/*
 * LCD.c
 *
 *  Created on: Oct 22, 2013
 *      Author: C15Jason.Mossing
 */
#include <msp430.h>
#include "LCD.h"

#define RS_MASK 0x40

char LCDCON = 0;

//initialize all of the implementation only functions

void writeCommandNibble(char commandNibble);

void writeCommandByte(char commandByte);

int getStringLength(char* string);

void writeDataByte(char dataByte);

void LCD_write_8(char byteToSend);

void LCD_write_4(char byteToSend);

void SPI_send(char byteToSend);

void set_SS_lo();

void set_SS_hi();


void clearLCD(){
	writeCommandByte(1);
}

void initSPI(){
	UCB0CTL1 |= UCSWRST;

	UCB0CTL0 |= UCCKPL|UCMSB|UCMST|UCSYNC;

	UCB0CTL1 |= UCSSEL1;

	UCB0STAT |= UCLISTEN;

	P1SEL |= BIT5|BIT6|BIT7;	//Clk(P1.5), SOMI(P1.6), SIMO(P1.7)
	P1SEL2 |= BIT5|BIT6|BIT7;

	P2DIR |= BIT1;		//GPIO for SS

	UCB0CTL1 &= ~UCSWRST;

}

void line1Cursor(){
	//0x02 is the set cursor to home command
	writeCommandByte(0x02);

}

void line2Cursor(){
	writeCommandByte(0x02);
	//moves the cursor to the right 40 times so it is on line 2 (2x40 screen)
	int i;
	for(i = 0; i < 40; i++){
		//0x14 is the shift the cursor to the right command
		writeCommandByte(0x14);
	}
}

void scrollString(char string1[], char string2[]){

	while(1){

	line1Cursor();
	writeString(string1);

	line2Cursor();
	writeString(string2);

	string1 = rotateString(string1);
	string2 = rotateString(string2);

	/*string1++;
	//there is a 0 (null) at the end of the string
	//this sees the null and resets the string.
	if(*string1 == 0){
		string1 = line1strg;
		}

	string2++;
		if(*string2 == 0){
		string2 = line2strg;
	}*/
		//delays the next shift by 100ms
    __delay_cycles(102000);
	}
}

char* rotateString(char string[]){
	int length = getStringLength(string);
	char last = string[0];
	int i;
	for(i = 0; i<length-1; i++){
		string[i] = string[i+1];
	}
	string[length-1] = last;

	return string;

}

void writeString(char* strg2Write){
	//goes to the null character at the end of the pointer
	while(*strg2Write != 0){
		writeChar(*strg2Write);
		strg2Write++;
	}
}

void writeChar(char char2Write){
	writeDataByte(char2Write);
}

void set_SS_lo(){
	P2OUT &= ~BIT1;
}

void set_SS_hi(){
	P2OUT |= BIT1;
}

void initLCD()
{
	set_SS_hi();

    writeCommandNibble(0x03);

    writeCommandNibble(0x03);

    writeCommandNibble(0x03);

    writeCommandNibble(0x02);

    writeCommandByte(0x28);

    writeCommandByte(0x0C);

    writeCommandByte(0x01);

    writeCommandByte(0x06);

    writeCommandByte(0x01);

    writeCommandByte(0x02);

    SPI_send(0);
    __delay_cycles(42);
}

void writeCommandNibble(char commandNibble)
{
    LCDCON &= ~RS_MASK;
    LCD_write_4(commandNibble);
    __delay_cycles(1698);
}

void writeCommandByte(char commandByte)
{
    LCDCON &= ~RS_MASK;
    LCD_write_8(commandByte);
    __delay_cycles(1698);
}

void writeDataByte(char dataByte)
{
    LCDCON |= RS_MASK;
    LCD_write_8(dataByte);
    __delay_cycles(42);
}

void LCD_write_8(char byteToSend)
{
    unsigned char sendByte = byteToSend;

    sendByte &= 0xF0;

    sendByte = sendByte >> 4;               // rotate to the right 4 times

    LCD_write_4(sendByte);

    sendByte = byteToSend;

    sendByte &= 0x0F;

    LCD_write_4(sendByte);
}

void LCD_write_4(char byteToSend)
{
    unsigned char sendByte = byteToSend;

    sendByte &= 0x0F;

    //Thanks to Coastie Ryan Hub I got this line!
    sendByte |= LCDCON;

    sendByte &= 0x7F;

    SPI_send(sendByte);

    __delay_cycles(42);

    sendByte |= 0x80;

    SPI_send(sendByte);

    __delay_cycles(42);

    sendByte &= 0x7F;

    SPI_send(sendByte);

    __delay_cycles(42);
}

void SPI_send(char byteToSend)
{
    char readByte;

    set_SS_lo();

    UCB0TXBUF = byteToSend;

    while(!(UCB0RXIFG & IFG2))
    {
        // wait until you've received a byte
    }

    readByte = UCB0RXBUF;

    set_SS_hi();
}

int getStringLength(char* string){
	int count = 0;
	while(*string != 0){
		count ++;
		string++;
	}
	return count;
}