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Diffstat (limited to 'drivers/avr/hd44780.c')
| -rw-r--r-- | drivers/avr/hd44780.c | 592 |
1 files changed, 592 insertions, 0 deletions
diff --git a/drivers/avr/hd44780.c b/drivers/avr/hd44780.c new file mode 100644 index 000000000..51414d8f9 --- /dev/null +++ b/drivers/avr/hd44780.c @@ -0,0 +1,592 @@ +/**************************************************************************** + 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 */ + |