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/*##############################################################*/
/* Author: Marcus Nasarek */
/* File: LCDH44780.h */
/* License: */
/* */
/* This program is free software; you can redistribute it */
/* and/or modify it under the terms of the GNU General */
/* Public License as published by the Free Software */
/* Foundation; either version 3 of the License, or */
/* (at your option) any later version. */
/* */
/* This program is distributed in the hope that it will */
/* be useful, but WITHOUT ANY WARRANTY; without even the */
/* implied warranty of MERCHANTABILITY or */
/* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General */
/* Public License for more details. */
/* */
/* You should have received a copy of the GNU General */
/* Public License along with this program; if not, */
/* see <http://www.gnu.org/licenses/>. */
/* */
/*##############################################################*/
// Thanks to Matt Hawkins (http://www.raspberrypi-spy.co.uk)
// The wiring for the LCD is as follows:
// 1 : GND
// 2 : 5V
// 3 : Contrast (0-5V)*
// 4 : RS (Register Select)
// 5 : R/W (Read Write) - GROUND THIS PIN
// 6 : Enable or Strobe
// 7 : Data Bit 0 - NOT USED
// 8 : Data Bit 1 - NOT USED
// 9 : Data Bit 2 - NOT USED
// 10: Data Bit 3 - NOT USED
// 11: Data Bit 4
// 12: Data Bit 5
// 13: Data Bit 6
// 14: Data Bit 7
// 15: LCD Backlight +5V**
// 16: LCD Backlight GND
#ifndef _LCDHD44780_H_
#define _LCDHD44780_H_
#include <stdlib.h>
#include <stdbool.h>
#include <stdio.h>
#include <string.h>
#include <stdbool.h>
#include <bcm2835.h>
// Define GPIO pin to LCD pin mapping
#define LCD_RS 21
#define LCD_E 20
#define LCD_D4 26
#define LCD_D5 19
#define LCD_D6 13
#define LCD_D7 6
// Define some device constants
// Maximum characters per line
#define LCD_WIDTH 16
#define LCD_DATA HIGH
#define LCD_CMD LOW
// Function set -
// Sets interface data length
// (DL), number of display lines
// (N), and character font (F).
// RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
// 0 0 0 0 1 DL N F - -
// DL = 0 --> 4 bit data length (1 = 8 bit)
// N = 1 --> 2 line display (0 = 1 line)
// F = 0 --> 5x8 dot character font
// F = 1 --> 5x10 dot character font
// 0x28 =
// 0 0 0 0 1 0 1 0 0 0
#define LCD_FUNCTION_SET 0x20
#define DATA_LENGTH 0x10
#define TWO_LINES 0x08
#define BIG_FONT_SET 0x04
// Display control flags
// Sets entire display (D) on/off,
// cursor on/off (C), and
// blinking of cursor position
// character (B).
// RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
// 0 0 0 0 0 0 1 D C B
// D = 1 --> display on
// C = 0 --> cursor off
// B = 0 --> blinking off
#define LCD_CONTROL 0x08 // display control
#define DISPLAY_ON 0x04
#define DISPLAY_OFF 0x00
#define CURSOR_ON 0x02
#define BLINKING_ON 0x01
// Entry mode set -
// Sets cursor move direction
// and specifies display shift.
// These operations are
// performed during data write
// and read.
// Execution time 37us
// RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
// 0 0 0 0 0 0 0 1 I/D S
// I/D = increment/decrement address pointer
// I/D = 1 --> increment
// S = 0 --> no shift
#define LCD_ENTRY_MODE 0x04
#define ADDR_INCREMENT 0x02
#define LINE_SHIFT 0x01
// Cursor or display shift -
// Moves the cursor and shifts
// display without chaning
// DDRAM contents.
// Execution time 37us
// RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
// 0 0 0 0 0 1 S/C R/L - -
// S/C = cursor/display shift
// S/C = 0 --> cursor shift
// R/L = shift direction
// R/L = 1 --> shift to right
#define CURSOR_DISPLAY_SHIFT 0x10
#define CURSOR_SHIFT 0x00
#define DISPLAY_SHIFT 0x08
#define SHIFT_RIGHT 0x04
#define SHIFT_LEFT 0x00
// LCD DDRAM address for the 1st line
// bits DB0..DB6 --> 0x00..0x4F
// DB7 = 1 --> offset = 0x80
// RS R/W DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
// 0 0 1 ADD ADD ADD ADD ADD ADD ADD
// 0x80 =
// 0 0 1 0 0 0 0 0 0 0
#define LCD_LINE_1 0x80
// LCD DDRAM address for the 2nd line
// 2 lines with equal # of addresses
// DB7 = 1 --> offset = 0x80 + (0x00..0x4F)/2 = 0xC0
#define LCD_LINE_2 0xC0
// Timing constants in us
#define E_DELAY 1 // us
#define E_CMD_PULSE 5000 // us
#define E_DATA_PULSE 5000 // us
#define C_DELAY 1 // us
#define R_EXEC_TIME 50 // us
#define GPIO_RISING 10 // ms
#define MAX_WAIT 100
void init_gpio(void);
void init_lcd(void);
void lcd_function_set(uint8_t control_flags);
void lcd_control(uint8_t control_flags);
void lcd_entry_mode(uint8_t control_flags);
void lcd_shift_control(uint8_t control_flags);
void clear_lcd(void);
void set_cursor(uint8_t addr);
void display_off(void);
void show_cursor(bool on);
void cursor_blinking(bool on);
void shift_cursor(uint8_t direction);
void shift_display(uint8_t direction);
void return_home(void);
void write_to_lcd(uint8_t byte, uint8_t mode);
void write_string(char *str);
uint8_t read_from_lcd(uint8_t mode);
void gpio_reset(void);
#endif
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