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Diffstat (limited to '3rd-party/LCDHD44780.h')
| -rw-r--r-- | 3rd-party/LCDHD44780.h | 198 |
1 files changed, 198 insertions, 0 deletions
diff --git a/3rd-party/LCDHD44780.h b/3rd-party/LCDHD44780.h new file mode 100644 index 0000000..d25f046 --- /dev/null +++ b/3rd-party/LCDHD44780.h @@ -0,0 +1,198 @@ +/*##############################################################*/ +/* 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 RPI_V2_GPIO_P1_26 +#define LCD_RW RPI_V2_GPIO_P1_07 +#define LCD_E RPI_V2_GPIO_P1_24 +#define LCD_D4 RPI_V2_GPIO_P1_22 +#define LCD_D5 RPI_V2_GPIO_P1_18 +#define LCD_D6 RPI_V2_GPIO_P1_16 +#define LCD_D7 RPI_V2_GPIO_P1_12 + +// 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); + +uint8_t busy_wait(void); + +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 |