avr-lcd-lib/lcdLib.c
Collin J. Doering 172d5e268f Prepare to support various escapes for characters
Move code that checked for escapes from the writeStringToLCD function to
the writeCharToLCD function.

Note: There seems to be an issue connecting to USART when the programmer
is not connected. This is likely a wiring issue related to ISP.

Signed-off-by: Collin J. Doering <collin.doering@rekahsoft.ca>
2015-10-06 05:49:59 -04:00

385 lines
11 KiB
C

/**
* (C) Copyright Collin J. Doering 2015
*
* 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/>.
*/
/**
* File: lcdLib.c
* Author: Collin J. Doering <collin.doering@rekahsoft.ca>
* Date: Sep 29, 2015
*/
#include <util/delay.h>
// Include header
#include "lcdLib.h"
// Globals
volatile uint8_t currentLineNum = 0;
volatile uint8_t currentLineChars = 0;
const uint8_t lineBeginnings[LCD_NUMBER_OF_LINES] = { LCD_LINE_BEGINNINGS };
//------------------------------------------------------------------------------------------
// Function definitions
void flashLED(uint8_t times) {
while (times > 0) {
STATUS_LED_PORT |= 1 << STATUS_LED; // turn on status LED
_delay_ms(100);
STATUS_LED_PORT &= ~(1 << STATUS_LED); // turn status LED off
_delay_ms(100);
times--;
}
}
//------------------------------------
void clkLCD(void) {
LCD_ENABLE_PORT |= (1 << LCD_ENABLE);
_delay_us(LCD_ENABLE_HIGH_DELAY);
LCD_ENABLE_PORT &= ~(1 << LCD_ENABLE);
_delay_us(LCD_ENABLE_LOW_DELAY);
}
void loop_until_LCD_BF_clear(void) {
uint8_t bf;
LCD_RS_PORT &= ~(1 << LCD_RS); // RS=0
LCD_RW_PORT |= (1 << LCD_RW); // RW=1
// Set LCD_BF as input
LCD_DBUS7_DDR &= ~(1 << LCD_BF);
STATUS_LED_PORT |= 1 << STATUS_LED; // DEBUG
do {
bf = 0;
LCD_ENABLE_PORT |= (1 << LCD_ENABLE);
_delay_us(1); // 'delay data time' and 'enable pulse width'
bf |= (LCD_DBUS7_PIN & (1 << LCD_BF));
LCD_ENABLE_PORT &= ~(1 << LCD_ENABLE);
_delay_us(1); // 'address hold time', 'data hold time' and 'enable cycle width'
#ifdef FOUR_BIT_MODE
LCD_ENABLE_PORT |= (1 << LCD_ENABLE);
_delay_us(1); // 'delay data time' and 'enable pulse width'
LCD_ENABLE_PORT &= ~(1 << LCD_ENABLE);
_delay_us(1); // 'address hold time', 'data hold time' and 'enable cycle width'
#endif
} while (bf);
STATUS_LED_PORT &= ~(1 << STATUS_LED); // DEBUG
#if defined (FOUR_BIT_MODE) || defined (EIGHT_BIT_ARBITRARY_PIN_MODE)
LCD_DBUS7_DDR |= (1 << LCD_DBUS7);
LCD_DBUS6_DDR |= (1 << LCD_DBUS6);
LCD_DBUS5_DDR |= (1 << LCD_DBUS5);
LCD_DBUS4_DDR |= (1 << LCD_DBUS4);
#ifdef EIGHT_BIT_ARBITRARY_PIN_MODE
LCD_DBUS3_DDR |= (1 << LCD_DBUS3);
LCD_DBUS2_DDR |= (1 << LCD_DBUS2);
LCD_DBUS1_DDR |= (1 << LCD_DBUS1);
LCD_DBUS0_DDR |= (1 << LCD_DBUS0);
#endif
#else
LCD_DBUS_DDR = 0xff; // Reset all LCD_DBUS_PORT pins as outputs
#endif
}
#ifdef FOUR_BIT_MODE
/*
Writes one nibble to the LCD data bus. Does not touch the RS or RW control lines.
Note: the bits that are sent are the four MSBs of the given argument
*/
void writeLCDNibble_(uint8_t b) {
// Reset data lines to zeros
LCD_DBUS7_PORT &= ~(1 << LCD_DBUS7);
LCD_DBUS6_PORT &= ~(1 << LCD_DBUS6);
LCD_DBUS5_PORT &= ~(1 << LCD_DBUS5);
LCD_DBUS4_PORT &= ~(1 << LCD_DBUS4);
// Write 1's where appropriate on data lines
if (b & (1 << 7)) LCD_DBUS7_PORT |= (1 << LCD_DBUS7);
if (b & (1 << 6)) LCD_DBUS6_PORT |= (1 << LCD_DBUS6);
if (b & (1 << 5)) LCD_DBUS5_PORT |= (1 << LCD_DBUS5);
if (b & (1 << 4)) LCD_DBUS4_PORT |= (1 << LCD_DBUS4);
// Pulse the enable line
clkLCD();
}
#endif
/*
Write a byte to the LCD data bus. Does not touch the RS or RW control lines.
*/
void writeLCDByte_(uint8_t b) {
#ifdef FOUR_BIT_MODE
writeLCDNibble_(b);
writeLCDNibble_(b << 4);
#elif defined (EIGHT_BIT_ARBITRARY_PIN_MODE)
// Reset data lines to zeros
LCD_DBUS7_PORT &= ~(1 << LCD_DBUS7);
LCD_DBUS6_PORT &= ~(1 << LCD_DBUS6);
LCD_DBUS5_PORT &= ~(1 << LCD_DBUS5);
LCD_DBUS4_PORT &= ~(1 << LCD_DBUS4);
LCD_DBUS3_PORT &= ~(1 << LCD_DBUS3);
LCD_DBUS2_PORT &= ~(1 << LCD_DBUS2);
LCD_DBUS1_PORT &= ~(1 << LCD_DBUS1);
LCD_DBUS0_PORT &= ~(1 << LCD_DBUS0);
// Write 1's where appropriate on data lines
if (b & (1 << 7)) LCD_DBUS7_PORT |= (1 << LCD_DBUS7);
if (b & (1 << 6)) LCD_DBUS6_PORT |= (1 << LCD_DBUS6);
if (b & (1 << 5)) LCD_DBUS5_PORT |= (1 << LCD_DBUS5);
if (b & (1 << 4)) LCD_DBUS4_PORT |= (1 << LCD_DBUS4);
if (b & (1 << 3)) LCD_DBUS3_PORT |= (1 << LCD_DBUS3);
if (b & (1 << 2)) LCD_DBUS2_PORT |= (1 << LCD_DBUS2);
if (b & (1 << 1)) LCD_DBUS1_PORT |= (1 << LCD_DBUS1);
if (b & (1 << 0)) LCD_DBUS0_PORT |= (1 << LCD_DBUS0);
clkLCD();
#else
LCD_DBUS_PORT = b;
clkLCD();
#endif
}
void writeLCDInstr_(uint8_t instr) {
LCD_RS_PORT &= ~(1 << LCD_RS); // RS=0
LCD_RW_PORT &= ~(1 << LCD_RW); // RW=0
#ifdef FOUR_BIT_MODE
writeLCDNibble_(instr);
writeLCDNibble_(instr << 4);
#else
writeLCDByte_(instr);
#endif
}
void writeLCDInstr(uint8_t instr) {
loop_until_LCD_BF_clear(); // Wait until LCD is ready for new instructions
writeLCDInstr_(instr);
}
void writeCharToLCD_(char c) {
LCD_RS_PORT |= (1 << LCD_RS); // RS=1
LCD_RW_PORT &= ~(1 << LCD_RW); // RW=0
#ifdef FOUR_BIT_MODE
writeLCDNibble_(c);
writeLCDNibble_(c << 4);
#else
writeLCDByte_(c);
#endif
}
void writeCharToLCD(char c) {
switch (c) {
case '\n': // Line feed
if (currentLineNum == LCD_NUMBER_OF_LINES - 1) {
clearDisplay();
} else {
writeLCDInstr(INSTR_DDRAM_ADDR | lineBeginnings[++currentLineNum]);
currentLineChars = 0;
}
break;
;
case '\a': // Alarm
break;
;
case '\b': // Backspace
break;
;
case '\r': // Carriage return
writeLCDInstr(INSTR_DDRAM_ADDR | lineBeginnings[currentLineNum]);
currentLineChars = 0;
break;
;
default:
if (currentLineChars == LCD_CHARACTERS_PER_LINE) {
if (currentLineNum == LCD_NUMBER_OF_LINES - 1) {
clearDisplay();
} else {
writeLCDInstr(INSTR_DDRAM_ADDR | lineBeginnings[++currentLineNum]);
currentLineChars = 0;
}
}
loop_until_LCD_BF_clear(); // Wait until LCD is ready for new instructions
writeCharToLCD_(c);
currentLineChars++;
;
}
}
void writeStringToLCD(const char* str) {
while (*str != '\0') {
writeCharToLCD(*str);
str++;
}
}
void clearDisplay(void) {
writeLCDInstr(CMD_CLEAR_DISPLAY);
// Reset line and char number tracking
currentLineNum = 0;
currentLineChars = 0;
}
void returnHome(void) {
writeLCDInstr(CMD_RETURN_HOME);
// Reset line and char number tracking
currentLineNum = 0;
currentLineChars = 0;
}
/* char readCharFromLCD(void) { */
/* loop_until_LCD_BF_clear(); // Wait until LCD is ready for new instructions */
/* LCD_CTRL_PORT |= (1 << LCD_RW) | (1 << LCD_RW); // RS=RW=1 */
/* LCD_DBUS_DDR = 0; // Set all LCD_DBUS_PORT pins as inputs */
/* clkLCD(); */
/* char c = LCD_DBUS_PIN; */
/* LCD_DBUS_DDR = 0xff; // Reset all LCD_DBUS_PORT pins to outputs */
/* return c; */
/* } */
/*
Set all pins of LCD_DBUS, as well as pins LCD_RS, and LCD_RW as outputs
*/
static inline void enableLCDOutput(void) {
LCD_RS_DDR |= (1 << LCD_RS);
LCD_RW_DDR |= (1 << LCD_RW);
LCD_ENABLE_DDR |= (1 << LCD_ENABLE);
#if defined (FOUR_BIT_MODE) || defined (EIGHT_BIT_ARBITRARY_PIN_MODE)
LCD_DBUS7_DDR |= (1 << LCD_DBUS7);
LCD_DBUS6_DDR |= (1 << LCD_DBUS6);
LCD_DBUS5_DDR |= (1 << LCD_DBUS5);
LCD_DBUS4_DDR |= (1 << LCD_DBUS4);
#ifdef EIGHT_BIT_ARBITRARY_PIN_MODE
LCD_DBUS3_DDR |= (1 << LCD_DBUS3);
LCD_DBUS2_DDR |= (1 << LCD_DBUS2);
LCD_DBUS1_DDR |= (1 << LCD_DBUS1);
LCD_DBUS0_DDR |= (1 << LCD_DBUS0);
#endif
#else
LCD_DBUS_DDR = 0xff;
#endif
}
/*
Set all pins of LCD_DBUS as well as LCD_RS, and LCD_RW as inputs (disabling their output)
*/
static inline void disableLCDOutput(void) {
LCD_RS_DDR &= ~(1 << LCD_RS);
LCD_RW_DDR &= ~(1 << LCD_RW);
LCD_ENABLE_DDR &= ~(1 << LCD_ENABLE);
#if defined (FOUR_BIT_MODE) || defined (EIGHT_BIT_ARBITRARY_PIN_MODE)
LCD_DBUS7_DDR &= ~(1 << LCD_DBUS7);
LCD_DBUS6_DDR &= ~(1 << LCD_DBUS6);
LCD_DBUS5_DDR &= ~(1 << LCD_DBUS5);
LCD_DBUS4_DDR &= ~(1 << LCD_DBUS4);
#ifdef EIGHT_BIT_ARBITRARY_PIN_MODE
LCD_DBUS3_DDR &= ~(1 << LCD_DBUS3);
LCD_DBUS2_DDR &= ~(1 << LCD_DBUS2);
LCD_DBUS1_DDR &= ~(1 << LCD_DBUS1);
LCD_DBUS0_DDR &= ~(1 << LCD_DBUS0);
#endif
#else
LCD_DBUS_DDR = 0;
#endif
}
static inline void softwareLCDInitPulse(void) {
enableLCDOutput();
LCD_RS_PORT &= ~(1 << LCD_RS); // RS=0
LCD_RW_PORT &= ~(1 << LCD_RW); // RW=0
#ifdef FOUR_BIT_MODE
writeLCDNibble_(CMD_INIT);
#else
writeLCDByte_(CMD_INIT);
#endif
}
/*
Do software initialization as specified by the datasheet
*/
void initLCD (void) {
enableLCDOutput();
_delay_us(LCD_INIT_DELAY0); // Wait minimum 15ms as per datasheet
softwareLCDInitPulse();
_delay_us(LCD_INIT_DELAY1); // Wait minimum 4.1ms as per datasheet
softwareLCDInitPulse();
_delay_us(LCD_INIT_DELAY2); // Wait minimum 100us as per datasheet
softwareLCDInitPulse();
#if defined (FOUR_BIT_MODE)
// Function Set (4-bit interface; 2 lines with 5x7 dot character font)
writeLCDNibble_(CMD_INIT_FOUR_BIT);
writeLCDInstr_(CMD_INIT_FOUR_BIT | (1 << INSTR_FUNC_SET_N));
#else
// Function set (8-bit interface; 2 lines with 5x7 dot character font)
// RS=RW=0, DBUS=b00111000,0x38
writeLCDInstr_(INSTR_FUNC_SET | (1 << INSTR_FUNC_SET_DL) | (1 << INSTR_FUNC_SET_N));
#endif
/* BF now can be checked */
// Set functions of LCD
writeLCDInstr_(INSTR_DISPLAY); // Display off
_delay_us(LCD_GENERIC_INSTR_DELAY);
// Clear display
writeLCDInstr_(CMD_CLEAR_DISPLAY);
_delay_us(LCD_CLEAR_DISPLAY_DELAY);
// Increment mode, no shift
writeLCDInstr_(INSTR_ENTRY_SET | (1 << INSTR_ENTRY_SET_ID));
_delay_us(LCD_GENERIC_INSTR_DELAY);
// Display on, cursor on, blink off
writeLCDInstr_(INSTR_DISPLAY | (1 << INSTR_DISPLAY_D) | (1 << INSTR_DISPLAY_C));
_delay_us(LCD_GENERIC_INSTR_DELAY);
flashLED(5); // DEBUG
}
/*
Initialize LCD using the internal reset circuitry.
Note: This currently only works with 8 bit modes, but is not recommended. Instead use the
initLCD function which uses the software initialization method and works for 8-bit
modes as well the 4-bit mode.
*/
void initLCDByInternalReset(void) {
enableLCDOutput();
// Function set (8-bit interface; 2 lines with 5x7 dot character font)
writeLCDInstr_(INSTR_FUNC_SET | (1 << INSTR_FUNC_SET_DL) | (1 << INSTR_FUNC_SET_N));
writeLCDInstr_(0x0F);
writeLCDInstr_(0x06);
writeLCDInstr_(CMD_CLEAR_DISPLAY);
_delay_ms(LCD_CLEAR_DISPLAY_DELAY);
}