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Diffstat (limited to 'platforms/avr/drivers/hd44780.c')
| -rw-r--r-- | platforms/avr/drivers/hd44780.c | 536 |
1 files changed, 536 insertions, 0 deletions
diff --git a/platforms/avr/drivers/hd44780.c b/platforms/avr/drivers/hd44780.c new file mode 100644 index 0000000000..f71069dece --- /dev/null +++ b/platforms/avr/drivers/hd44780.c @@ -0,0 +1,536 @@ +/**************************************************************************** + Title: HD44780U LCD library + Author: Peter Fleury <pfleury@gmx.ch> http://tinyurl.com/peterfleury + License: GNU General Public License Version 3 + File: $Id: lcd.c,v 1.15.2.2 2015/01/17 12:16:05 peter Exp $ + Software: AVR-GCC 3.3 + Target: any AVR device, memory mapped mode only for AT90S4414/8515/Mega + + DESCRIPTION + Basic routines for interfacing a HD44780U-based text lcd display + + Originally based on Volker Oth's lcd library, + changed lcd_init(), added additional constants for lcd_command(), + added 4-bit I/O mode, improved and optimized code. + + Library can be operated in memory mapped mode (LCD_IO_MODE=0) or in + 4-bit IO port mode (LCD_IO_MODE=1). 8-bit IO port mode not supported. + + Memory mapped mode compatible with Kanda STK200, but supports also + generation of R/W signal through A8 address line. + + USAGE + See the C include lcd.h file for a description of each function + +*****************************************************************************/ +#include <inttypes.h> +#include <avr/io.h> +#include <avr/pgmspace.h> +#include <util/delay.h> +#include "hd44780.h" + +/* +** constants/macros +*/ +#define DDR(x) (*(&x - 1)) /* address of data direction register of port x */ +#if defined(__AVR_ATmega64__) || defined(__AVR_ATmega128__) +/* on ATmega64/128 PINF is on port 0x00 and not 0x60 */ +# define PIN(x) (&PORTF == &(x) ? _SFR_IO8(0x00) : (*(&x - 2))) +#else +# define PIN(x) (*(&x - 2)) /* address of input register of port x */ +#endif + +#if LCD_IO_MODE +# define lcd_e_delay() _delay_us(LCD_DELAY_ENABLE_PULSE) +# define lcd_e_high() LCD_E_PORT |= _BV(LCD_E_PIN); +# define lcd_e_low() LCD_E_PORT &= ~_BV(LCD_E_PIN); +# define lcd_e_toggle() toggle_e() +# define lcd_rw_high() LCD_RW_PORT |= _BV(LCD_RW_PIN) +# define lcd_rw_low() LCD_RW_PORT &= ~_BV(LCD_RW_PIN) +# define lcd_rs_high() LCD_RS_PORT |= _BV(LCD_RS_PIN) +# define lcd_rs_low() LCD_RS_PORT &= ~_BV(LCD_RS_PIN) +#endif + +#if LCD_IO_MODE +# if LCD_LINES == 1 +# define LCD_FUNCTION_DEFAULT LCD_FUNCTION_4BIT_1LINE +# else +# define LCD_FUNCTION_DEFAULT LCD_FUNCTION_4BIT_2LINES +# endif +#else +# if LCD_LINES == 1 +# define LCD_FUNCTION_DEFAULT LCD_FUNCTION_8BIT_1LINE +# else +# define LCD_FUNCTION_DEFAULT LCD_FUNCTION_8BIT_2LINES +# endif +#endif + +#if LCD_CONTROLLER_KS0073 +# if LCD_LINES == 4 + +# define KS0073_EXTENDED_FUNCTION_REGISTER_ON 0x2C /* |0|010|1100 4-bit mode, extension-bit RE = 1 */ +# define KS0073_EXTENDED_FUNCTION_REGISTER_OFF 0x28 /* |0|010|1000 4-bit mode, extension-bit RE = 0 */ +# define KS0073_4LINES_MODE 0x09 /* |0|000|1001 4 lines mode */ + +# endif +#endif + +/* +** function prototypes +*/ +#if LCD_IO_MODE +static void toggle_e(void); +#endif + +/* +** local functions +*/ + +/************************************************************************* +delay for a minimum of <us> microseconds +the number of loops is calculated at compile-time from MCU clock frequency +*************************************************************************/ +#define delay(us) _delay_us(us) + +#if LCD_IO_MODE +/* toggle Enable Pin to initiate write */ +static void toggle_e(void) { + lcd_e_high(); + lcd_e_delay(); + lcd_e_low(); +} +#endif + +/************************************************************************* +Low-level function to write byte to LCD controller +Input: data byte to write to LCD + rs 1: write data + 0: write instruction +Returns: none +*************************************************************************/ +#if LCD_IO_MODE +static void lcd_write(uint8_t data, uint8_t rs) { + unsigned char dataBits; + + if (rs) { /* write data (RS=1, RW=0) */ + lcd_rs_high(); + } else { /* write instruction (RS=0, RW=0) */ + lcd_rs_low(); + } + lcd_rw_low(); /* RW=0 write mode */ + + if ((&LCD_DATA0_PORT == &LCD_DATA1_PORT) && (&LCD_DATA1_PORT == &LCD_DATA2_PORT) && (&LCD_DATA2_PORT == &LCD_DATA3_PORT) && (LCD_DATA0_PIN == 0) && (LCD_DATA1_PIN == 1) && (LCD_DATA2_PIN == 2) && (LCD_DATA3_PIN == 3)) { + /* configure data pins as output */ + DDR(LCD_DATA0_PORT) |= 0x0F; + + /* output high nibble first */ + dataBits = LCD_DATA0_PORT & 0xF0; + LCD_DATA0_PORT = dataBits | ((data >> 4) & 0x0F); + lcd_e_toggle(); + + /* output low nibble */ + LCD_DATA0_PORT = dataBits | (data & 0x0F); + lcd_e_toggle(); + + /* all data pins high (inactive) */ + LCD_DATA0_PORT = dataBits | 0x0F; + } else { + /* configure data pins as output */ + DDR(LCD_DATA0_PORT) |= _BV(LCD_DATA0_PIN); + DDR(LCD_DATA1_PORT) |= _BV(LCD_DATA1_PIN); + DDR(LCD_DATA2_PORT) |= _BV(LCD_DATA2_PIN); + DDR(LCD_DATA3_PORT) |= _BV(LCD_DATA3_PIN); + + /* output high nibble first */ + LCD_DATA3_PORT &= ~_BV(LCD_DATA3_PIN); + LCD_DATA2_PORT &= ~_BV(LCD_DATA2_PIN); + LCD_DATA1_PORT &= ~_BV(LCD_DATA1_PIN); + LCD_DATA0_PORT &= ~_BV(LCD_DATA0_PIN); + if (data & 0x80) LCD_DATA3_PORT |= _BV(LCD_DATA3_PIN); + if (data & 0x40) LCD_DATA2_PORT |= _BV(LCD_DATA2_PIN); + if (data & 0x20) LCD_DATA1_PORT |= _BV(LCD_DATA1_PIN); + if (data & 0x10) LCD_DATA0_PORT |= _BV(LCD_DATA0_PIN); + lcd_e_toggle(); + + /* output low nibble */ + LCD_DATA3_PORT &= ~_BV(LCD_DATA3_PIN); + LCD_DATA2_PORT &= ~_BV(LCD_DATA2_PIN); + LCD_DATA1_PORT &= ~_BV(LCD_DATA1_PIN); + LCD_DATA0_PORT &= ~_BV(LCD_DATA0_PIN); + if (data & 0x08) LCD_DATA3_PORT |= _BV(LCD_DATA3_PIN); + if (data & 0x04) LCD_DATA2_PORT |= _BV(LCD_DATA2_PIN); + if (data & 0x02) LCD_DATA1_PORT |= _BV(LCD_DATA1_PIN); + if (data & 0x01) LCD_DATA0_PORT |= _BV(LCD_DATA0_PIN); + lcd_e_toggle(); + + /* all data pins high (inactive) */ + LCD_DATA0_PORT |= _BV(LCD_DATA0_PIN); + LCD_DATA1_PORT |= _BV(LCD_DATA1_PIN); + LCD_DATA2_PORT |= _BV(LCD_DATA2_PIN); + LCD_DATA3_PORT |= _BV(LCD_DATA3_PIN); + } +} +#else +# define lcd_write(d, rs) \ + if (rs) \ + *(volatile uint8_t *)(LCD_IO_DATA) = d; \ + else \ + *(volatile uint8_t *)(LCD_IO_FUNCTION) = d; +/* rs==0 -> write instruction to LCD_IO_FUNCTION */ +/* rs==1 -> write data to LCD_IO_DATA */ +#endif + +/************************************************************************* +Low-level function to read byte from LCD controller +Input: rs 1: read data + 0: read busy flag / address counter +Returns: byte read from LCD controller +*************************************************************************/ +#if LCD_IO_MODE +static uint8_t lcd_read(uint8_t rs) { + uint8_t data; + + if (rs) + lcd_rs_high(); /* RS=1: read data */ + else + lcd_rs_low(); /* RS=0: read busy flag */ + lcd_rw_high(); /* RW=1 read mode */ + + if ((&LCD_DATA0_PORT == &LCD_DATA1_PORT) && (&LCD_DATA1_PORT == &LCD_DATA2_PORT) && (&LCD_DATA2_PORT == &LCD_DATA3_PORT) && (LCD_DATA0_PIN == 0) && (LCD_DATA1_PIN == 1) && (LCD_DATA2_PIN == 2) && (LCD_DATA3_PIN == 3)) { + DDR(LCD_DATA0_PORT) &= 0xF0; /* configure data pins as input */ + + lcd_e_high(); + lcd_e_delay(); + data = PIN(LCD_DATA0_PORT) << 4; /* read high nibble first */ + lcd_e_low(); + + lcd_e_delay(); /* Enable 500ns low */ + + lcd_e_high(); + lcd_e_delay(); + data |= PIN(LCD_DATA0_PORT) & 0x0F; /* read low nibble */ + lcd_e_low(); + } else { + /* configure data pins as input */ + DDR(LCD_DATA0_PORT) &= ~_BV(LCD_DATA0_PIN); + DDR(LCD_DATA1_PORT) &= ~_BV(LCD_DATA1_PIN); + DDR(LCD_DATA2_PORT) &= ~_BV(LCD_DATA2_PIN); + DDR(LCD_DATA3_PORT) &= ~_BV(LCD_DATA3_PIN); + + /* read high nibble first */ + lcd_e_high(); + lcd_e_delay(); + data = 0; + if (PIN(LCD_DATA0_PORT) & _BV(LCD_DATA0_PIN)) data |= 0x10; + if (PIN(LCD_DATA1_PORT) & _BV(LCD_DATA1_PIN)) data |= 0x20; + if (PIN(LCD_DATA2_PORT) & _BV(LCD_DATA2_PIN)) data |= 0x40; + if (PIN(LCD_DATA3_PORT) & _BV(LCD_DATA3_PIN)) data |= 0x80; + lcd_e_low(); + + lcd_e_delay(); /* Enable 500ns low */ + + /* read low nibble */ + lcd_e_high(); + lcd_e_delay(); + if (PIN(LCD_DATA0_PORT) & _BV(LCD_DATA0_PIN)) data |= 0x01; + if (PIN(LCD_DATA1_PORT) & _BV(LCD_DATA1_PIN)) data |= 0x02; + if (PIN(LCD_DATA2_PORT) & _BV(LCD_DATA2_PIN)) data |= 0x04; + if (PIN(LCD_DATA3_PORT) & _BV(LCD_DATA3_PIN)) data |= 0x08; + lcd_e_low(); + } + return data; +} +#else +# define lcd_read(rs) (rs) ? *(volatile uint8_t *)(LCD_IO_DATA + LCD_IO_READ) : *(volatile uint8_t *)(LCD_IO_FUNCTION + LCD_IO_READ) +/* rs==0 -> read instruction from LCD_IO_FUNCTION */ +/* rs==1 -> read data from LCD_IO_DATA */ +#endif + +/************************************************************************* +loops while lcd is busy, returns address counter +*************************************************************************/ +static uint8_t lcd_waitbusy(void) + +{ + register uint8_t c; + + /* wait until busy flag is cleared */ + while ((c = lcd_read(0)) & (1 << LCD_BUSY)) { + } + + /* the address counter is updated 4us after the busy flag is cleared */ + delay(LCD_DELAY_BUSY_FLAG); + + /* now read the address counter */ + return (lcd_read(0)); // return address counter + +} /* lcd_waitbusy */ + +/************************************************************************* +Move cursor to the start of next line or to the first line if the cursor +is already on the last line. +*************************************************************************/ +static inline void lcd_newline(uint8_t pos) { + register uint8_t addressCounter; + +#if LCD_LINES == 1 + addressCounter = 0; +#endif +#if LCD_LINES == 2 + if (pos < (LCD_START_LINE2)) + addressCounter = LCD_START_LINE2; + else + addressCounter = LCD_START_LINE1; +#endif +#if LCD_LINES == 4 +# if KS0073_4LINES_MODE + if (pos < LCD_START_LINE2) + addressCounter = LCD_START_LINE2; + else if ((pos >= LCD_START_LINE2) && (pos < LCD_START_LINE3)) + addressCounter = LCD_START_LINE3; + else if ((pos >= LCD_START_LINE3) && (pos < LCD_START_LINE4)) + addressCounter = LCD_START_LINE4; + else + addressCounter = LCD_START_LINE1; +# else + if (pos < LCD_START_LINE3) + addressCounter = LCD_START_LINE2; + else if ((pos >= LCD_START_LINE2) && (pos < LCD_START_LINE4)) + addressCounter = LCD_START_LINE3; + else if ((pos >= LCD_START_LINE3) && (pos < LCD_START_LINE2)) + addressCounter = LCD_START_LINE4; + else + addressCounter = LCD_START_LINE1; +# endif +#endif + lcd_command((1 << LCD_DDRAM) + addressCounter); + +} /* lcd_newline */ + +/* +** PUBLIC FUNCTIONS +*/ + +/************************************************************************* +Send LCD controller instruction command +Input: instruction to send to LCD controller, see HD44780 data sheet +Returns: none +*************************************************************************/ +void lcd_command(uint8_t cmd) { + lcd_waitbusy(); + lcd_write(cmd, 0); +} + +/************************************************************************* +Send data byte to LCD controller +Input: data to send to LCD controller, see HD44780 data sheet +Returns: none +*************************************************************************/ +void lcd_data(uint8_t data) { + lcd_waitbusy(); + lcd_write(data, 1); +} + +/************************************************************************* +Set cursor to specified position +Input: x horizontal position (0: left most position) + y vertical position (0: first line) +Returns: none +*************************************************************************/ +void lcd_gotoxy(uint8_t x, uint8_t y) { +#if LCD_LINES == 1 + lcd_command((1 << LCD_DDRAM) + LCD_START_LINE1 + x); +#endif +#if LCD_LINES == 2 + if (y == 0) + lcd_command((1 << LCD_DDRAM) + LCD_START_LINE1 + x); + else + lcd_command((1 << LCD_DDRAM) + LCD_START_LINE2 + x); +#endif +#if LCD_LINES == 4 + if (y == 0) + lcd_command((1 << LCD_DDRAM) + LCD_START_LINE1 + x); + else if (y == 1) + lcd_command((1 << LCD_DDRAM) + LCD_START_LINE2 + x); + else if (y == 2) + lcd_command((1 << LCD_DDRAM) + LCD_START_LINE3 + x); + else /* y==3 */ + lcd_command((1 << LCD_DDRAM) + LCD_START_LINE4 + x); +#endif + +} /* lcd_gotoxy */ + +/************************************************************************* +*************************************************************************/ +int lcd_getxy(void) { return lcd_waitbusy(); } + +/************************************************************************* +Clear display and set cursor to home position +*************************************************************************/ +void lcd_clrscr(void) { lcd_command(1 << LCD_CLR); } + +/************************************************************************* +Set cursor to home position +*************************************************************************/ +void lcd_home(void) { lcd_command(1 << LCD_HOME); } + +/************************************************************************* +Display character at current cursor position +Input: character to be displayed +Returns: none +*************************************************************************/ +void lcd_putc(char c) { + uint8_t pos; + + pos = lcd_waitbusy(); // read busy-flag and address counter + if (c == '\n') { + lcd_newline(pos); + } else { +#if LCD_WRAP_LINES == 1 +# if LCD_LINES == 1 + if (pos == LCD_START_LINE1 + LCD_DISP_LENGTH) { + lcd_write((1 << LCD_DDRAM) + LCD_START_LINE1, 0); + } +# elif LCD_LINES == 2 + if (pos == LCD_START_LINE1 + LCD_DISP_LENGTH) { + lcd_write((1 << LCD_DDRAM) + LCD_START_LINE2, 0); + } else if (pos == LCD_START_LINE2 + LCD_DISP_LENGTH) { + lcd_write((1 << LCD_DDRAM) + LCD_START_LINE1, 0); + } +# elif LCD_LINES == 4 + if (pos == LCD_START_LINE1 + LCD_DISP_LENGTH) { + lcd_write((1 << LCD_DDRAM) + LCD_START_LINE2, 0); + } else if (pos == LCD_START_LINE2 + LCD_DISP_LENGTH) { + lcd_write((1 << LCD_DDRAM) + LCD_START_LINE3, 0); + } else if (pos == LCD_START_LINE3 + LCD_DISP_LENGTH) { + lcd_write((1 << LCD_DDRAM) + LCD_START_LINE4, 0); + } else if (pos == LCD_START_LINE4 + LCD_DISP_LENGTH) { + lcd_write((1 << LCD_DDRAM) + LCD_START_LINE1, 0); + } +# endif + lcd_waitbusy(); +#endif + lcd_write(c, 1); + } + +} /* lcd_putc */ + +/************************************************************************* +Display string without auto linefeed +Input: string to be displayed +Returns: none +*************************************************************************/ +void lcd_puts(const char *s) +/* print string on lcd (no auto linefeed) */ +{ + register char c; + + while ((c = *s++)) { + lcd_putc(c); + } + +} /* lcd_puts */ + +/************************************************************************* +Display string from program memory without auto linefeed +Input: string from program memory be be displayed +Returns: none +*************************************************************************/ +void lcd_puts_p(const char *progmem_s) +/* print string from program memory on lcd (no auto linefeed) */ +{ + register char c; + + while ((c = pgm_read_byte(progmem_s++))) { + lcd_putc(c); + } + +} /* lcd_puts_p */ + +/************************************************************************* +Initialize display and select type of cursor +Input: dispAttr LCD_DISP_OFF display off + LCD_DISP_ON display on, cursor off + LCD_DISP_ON_CURSOR display on, cursor on + LCD_DISP_CURSOR_BLINK display on, cursor on flashing +Returns: none +*************************************************************************/ +void lcd_init(uint8_t dispAttr) { +#if LCD_IO_MODE + /* + * Initialize LCD to 4 bit I/O mode + */ + + if ((&LCD_DATA0_PORT == &LCD_DATA1_PORT) && (&LCD_DATA1_PORT == &LCD_DATA2_PORT) && (&LCD_DATA2_PORT == &LCD_DATA3_PORT) && (&LCD_RS_PORT == &LCD_DATA0_PORT) && (&LCD_RW_PORT == &LCD_DATA0_PORT) && (&LCD_E_PORT == &LCD_DATA0_PORT) && (LCD_DATA0_PIN == 0) && (LCD_DATA1_PIN == 1) && (LCD_DATA2_PIN == 2) && (LCD_DATA3_PIN == 3) && (LCD_RS_PIN == 4) && (LCD_RW_PIN == 5) && (LCD_E_PIN == 6)) { + /* configure all port bits as output (all LCD lines on same port) */ + DDR(LCD_DATA0_PORT) |= 0x7F; + } else if ((&LCD_DATA0_PORT == &LCD_DATA1_PORT) && (&LCD_DATA1_PORT == &LCD_DATA2_PORT) && (&LCD_DATA2_PORT == &LCD_DATA3_PORT) && (LCD_DATA0_PIN == 0) && (LCD_DATA1_PIN == 1) && (LCD_DATA2_PIN == 2) && (LCD_DATA3_PIN == 3)) { + /* configure all port bits as output (all LCD data lines on same port, but control lines on different ports) */ + DDR(LCD_DATA0_PORT) |= 0x0F; + DDR(LCD_RS_PORT) |= _BV(LCD_RS_PIN); + DDR(LCD_RW_PORT) |= _BV(LCD_RW_PIN); + DDR(LCD_E_PORT) |= _BV(LCD_E_PIN); + } else { + /* configure all port bits as output (LCD data and control lines on different ports */ + DDR(LCD_RS_PORT) |= _BV(LCD_RS_PIN); + DDR(LCD_RW_PORT) |= _BV(LCD_RW_PIN); + DDR(LCD_E_PORT) |= _BV(LCD_E_PIN); + DDR(LCD_DATA0_PORT) |= _BV(LCD_DATA0_PIN); + DDR(LCD_DATA1_PORT) |= _BV(LCD_DATA1_PIN); + DDR(LCD_DATA2_PORT) |= _BV(LCD_DATA2_PIN); + DDR(LCD_DATA3_PORT) |= _BV(LCD_DATA3_PIN); + } + delay(LCD_DELAY_BOOTUP); /* wait 16ms or more after power-on */ + + /* initial write to lcd is 8bit */ + LCD_DATA1_PORT |= _BV(LCD_DATA1_PIN); // LCD_FUNCTION>>4; + LCD_DATA0_PORT |= _BV(LCD_DATA0_PIN); // LCD_FUNCTION_8BIT>>4; + lcd_e_toggle(); + delay(LCD_DELAY_INIT); /* delay, busy flag can't be checked here */ + + /* repeat last command */ + lcd_e_toggle(); + delay(LCD_DELAY_INIT_REP); /* delay, busy flag can't be checked here */ + + /* repeat last command a third time */ + lcd_e_toggle(); + delay(LCD_DELAY_INIT_REP); /* delay, busy flag can't be checked here */ + + /* now configure for 4bit mode */ + LCD_DATA0_PORT &= ~_BV(LCD_DATA0_PIN); // LCD_FUNCTION_4BIT_1LINE>>4 + lcd_e_toggle(); + delay(LCD_DELAY_INIT_4BIT); /* some displays need this additional delay */ + + /* from now the LCD only accepts 4 bit I/O, we can use lcd_command() */ +#else + /* + * Initialize LCD to 8 bit memory mapped mode + */ + + /* enable external SRAM (memory mapped lcd) and one wait state */ + MCUCR = _BV(SRE) | _BV(SRW); + + /* reset LCD */ + delay(LCD_DELAY_BOOTUP); /* wait 16ms after power-on */ + lcd_write(LCD_FUNCTION_8BIT_1LINE, 0); /* function set: 8bit interface */ + delay(LCD_DELAY_INIT); /* wait 5ms */ + lcd_write(LCD_FUNCTION_8BIT_1LINE, 0); /* function set: 8bit interface */ + delay(LCD_DELAY_INIT_REP); /* wait 64us */ + lcd_write(LCD_FUNCTION_8BIT_1LINE, 0); /* function set: 8bit interface */ + delay(LCD_DELAY_INIT_REP); /* wait 64us */ +#endif + +#if KS0073_4LINES_MODE + /* Display with KS0073 controller requires special commands for enabling 4 line mode */ + lcd_command(KS0073_EXTENDED_FUNCTION_REGISTER_ON); + lcd_command(KS0073_4LINES_MODE); + lcd_command(KS0073_EXTENDED_FUNCTION_REGISTER_OFF); +#else + lcd_command(LCD_FUNCTION_DEFAULT); /* function set: display lines */ +#endif + lcd_command(LCD_DISP_OFF); /* display off */ + lcd_clrscr(); /* display clear */ + lcd_command(LCD_MODE_DEFAULT); /* set entry mode */ + lcd_command(dispAttr); /* display/cursor control */ + +} /* lcd_init */ |