//-----------------------------------------------------------------------------------------
// FUNCTION: lcd_write
// PURPOSE: send a character or an instruction to the LCD
void lcd_write(uint8_t data, uint8_t rs)
{
_delay_us(1000);
//check write type
if (rs)
lcd_rs_high(); //write data
else
lcd_rs_low(); //write instruciton
// configure data pins as output
LCD_DDR(LCD_DATA0_PORT) |= _BV(LCD_DATA0_PIN);
LCD_DDR(LCD_DATA1_PORT) |= _BV(LCD_DATA1_PIN);
LCD_DDR(LCD_DATA2_PORT) |= _BV(LCD_DATA2_PIN);
LCD_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_toggle_e();
// 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_toggle_e();
// 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);
}
// PURPOSE: send a character or an instruction to the LCD
void HD44780::lcd_write(uint8_t data,uint8_t rs)
{
// we cannot check LCD status (no read available) , so we will assume a default delay to wait for lcd to be ready
fcpu_delay_us(500);
//check write type
if (rs)
lcd_rs_high(); //write data
else
lcd_rs_low(); //write instruciton
// configure data pins as output
LCD_DDR(LCD_4BIT_D4_PORT) |= _BV(LCD_4BIT_D4_PIN);
LCD_DDR(LCD_4BIT_D5_PORT) |= _BV(LCD_4BIT_D5_PIN);
LCD_DDR(LCD_4BIT_D6_PORT) |= _BV(LCD_4BIT_D6_PIN);
LCD_DDR(LCD_4BIT_D7_PORT) |= _BV(LCD_4BIT_D7_PIN);
// output high nibble first
LCD_4BIT_D7_PORT &= ~_BV(LCD_4BIT_D7_PIN);
LCD_4BIT_D6_PORT &= ~_BV(LCD_4BIT_D6_PIN);
LCD_4BIT_D5_PORT &= ~_BV(LCD_4BIT_D5_PIN);
LCD_4BIT_D4_PORT &= ~_BV(LCD_4BIT_D4_PIN);
if(data & 0x80) LCD_4BIT_D7_PORT |= _BV(LCD_4BIT_D7_PIN);
if(data & 0x40) LCD_4BIT_D6_PORT |= _BV(LCD_4BIT_D6_PIN);
if(data & 0x20) LCD_4BIT_D5_PORT |= _BV(LCD_4BIT_D5_PIN);
if(data & 0x10) LCD_4BIT_D4_PORT |= _BV(LCD_4BIT_D4_PIN);
lcd_toggle_e();
// output low nibble
LCD_4BIT_D7_PORT &= ~_BV(LCD_4BIT_D7_PIN);
LCD_4BIT_D6_PORT &= ~_BV(LCD_4BIT_D6_PIN);
LCD_4BIT_D5_PORT &= ~_BV(LCD_4BIT_D5_PIN);
LCD_4BIT_D4_PORT &= ~_BV(LCD_4BIT_D4_PIN);
if(data & 0x08) LCD_4BIT_D7_PORT |= _BV(LCD_4BIT_D7_PIN);
if(data & 0x04) LCD_4BIT_D6_PORT |= _BV(LCD_4BIT_D6_PIN);
if(data & 0x02) LCD_4BIT_D5_PORT |= _BV(LCD_4BIT_D5_PIN);
if(data & 0x01) LCD_4BIT_D4_PORT |= _BV(LCD_4BIT_D4_PIN);
lcd_toggle_e();
// all data pins high (inactive)
LCD_4BIT_D4_PORT |= _BV(LCD_4BIT_D4_PIN);
LCD_4BIT_D5_PORT |= _BV(LCD_4BIT_D5_PIN);
LCD_4BIT_D6_PORT |= _BV(LCD_4BIT_D6_PIN);
LCD_4BIT_D7_PORT |= _BV(LCD_4BIT_D7_PIN);
}
// PURPOSE: Initialize LCD to 4 bit I/O mode
void HD44780::lcd_init()
{
// configure all port bits as output (LCD data and control lines on different ports
LCD_DDR(LCD_RS_PORT) |= _BV(LCD_RS_PIN);
LCD_DDR(LCD_E_PORT) |= _BV(LCD_E_PIN);
LCD_DDR(LCD_4BIT_D4_PORT) |= _BV(LCD_4BIT_D4_PIN);
LCD_DDR(LCD_4BIT_D5_PORT) |= _BV(LCD_4BIT_D5_PIN);
LCD_DDR(LCD_4BIT_D6_PORT) |= _BV(LCD_4BIT_D6_PIN);
LCD_DDR(LCD_4BIT_D7_PORT) |= _BV(LCD_4BIT_D7_PIN);
// wait 25ms or more after power-on
fcpu_delay_us(25000);
// initial write to lcd is 8bit
LCD_4BIT_D5_PORT |= _BV(LCD_4BIT_D5_PIN); // _BV(LCD_FUNCTION)>>4;
LCD_4BIT_D4_PORT |= _BV(LCD_4BIT_D4_PIN); // _BV(LCD_FUNCTION_8BIT)>>4;
lcd_toggle_e();
fcpu_delay_us(2000); //2000 // delay, busy flag can't be checked here
// repeat last command
lcd_toggle_e();
fcpu_delay_us(64); //64 // delay, busy flag can't be checked here
// now configure for 4bit mode
LCD_4BIT_D4_PORT &= ~_BV(LCD_4BIT_D4_PIN); // LCD_FUNCTION_4BIT_1LINE>>4
lcd_toggle_e();
fcpu_delay_us(2000); // some displays need this additional delay
// set 4 bit IO
lcd_instr(LCD_FUNCTION_4BIT_2LINES); // 4-bit interface, dual line, 5x7 dots
lcd_toggle_e();
fcpu_delay_us(2000); // some displays need this additional delay
lcd_instr(LCD_ENTRY_INC_);//cursor move right, no shift display
lcd_toggle_e();
fcpu_delay_us(2500); // some displays need this additional delay
lcd_instr(LCD_DISP_ON);// display on, cursor off, blink char off
lcd_toggle_e();
fcpu_delay_us(2500); // some displays need this additional delay
lcd_home();//set cursor to home and clear the cursor
}
