?? lcd_4bit.c
字號:
/******************************************************************************/
/* LCD.c: Functions for 2 line 16 character Text LCD, with 4-bit interface */
/******************************************************************************/
/* This file is part of the uVision/ARM development tools. */
/* Copyright (c) 2005-2006 Keil Software. All rights reserved. */
/* This software may only be used under the terms of a valid, current, */
/* end user licence from KEIL for a compatible version of KEIL software */
/* development tools. Nothing else gives you the right to use this software. */
/******************************************************************************/
#include <LPC23xx.H> /* LPC23xx definitions */
/*********************** Hardware specific configuration **********************/
/*------------------------- Speed dependant settings -------------------------*/
/* If processor works on high frequency delay has to be increased, it can be
increased by factor 2^N by this constant */
#define DELAY_2N 0
/*------------------------- Text LCD size definitions ------------------------*/
#define LineLen 16 /* Width (in characters) */
#define NumLines 2 /* Hight (in lines) */
/*-------------------- LCD interface hardware definitions --------------------*/
/* PINS:
- DB4 = P1.24
- DB5 = P1.25
- DB6 = P1.26
- DB7 = P1.27
- E = P1.31 (for V1 P1.30)
- RW = P1.29
- RS = P1.28 */
#define MCB2300_V1 /* First version of MCB2300 */
#define PIN_E 0x80000000
#define PIN_RW 0x20000000
#define PIN_RS 0x10000000
#define PINS_CTRL 0xB0000000
#define PINS_DATA 0x0F000000
#ifdef MCB2300_V1
#undef PIN_E
#define PIN_E 0xC0000000
#undef PINS_CTRL
#define PINS_CTRL 0xF0000000
#endif
/* pin E setting to 0 or 1 */
#define LCD_E(x) ((x) ? (IOSET1 = PIN_E) : (IOCLR1 = PIN_E) );
/* pin RW setting to 0 or 1 */
#define LCD_RW(x) ((x) ? (IOSET1 = PIN_RW) : (IOCLR1 = PIN_RW));
/* pin RS setting to 0 or 1 */
#define LCD_RS(x) ((x) ? (IOSET1 = PIN_RS) : (IOCLR1 = PIN_RS));
/* Reading DATA pins */
#define LCD_DATA_IN ((IOPIN1 >> 24) & 0xF)
/* Writing value to DATA pins */
#define LCD_DATA_OUT(x) IOCLR1 = PINS_DATA; IOSET1 = (x & 0xF) << 24;
/* Setting all pins to output mode */
#define LCD_ALL_DIR_OUT IODIR1 |= PINS_CTRL | PINS_DATA;
/* Setting DATA pins to input mode */
#define LCD_DATA_DIR_IN IODIR1 &= ~PINS_DATA;
/* Setting DATA pins to output mode */
#define LCD_DATA_DIR_OUT IODIR1 |= PINS_DATA;
/******************************************************************************/
/* 8 user defined characters to be loaded into CGRAM (used for bargraph) */
const unsigned char UserFont[8][8] = {
{ 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 },
{ 0x10,0x10,0x10,0x10,0x10,0x10,0x10,0x10 },
{ 0x18,0x18,0x18,0x18,0x18,0x18,0x18,0x18 },
{ 0x1C,0x1C,0x1C,0x1C,0x1C,0x1C,0x1C,0x1C },
{ 0x1E,0x1E,0x1E,0x1E,0x1E,0x1E,0x1E,0x1E },
{ 0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F },
{ 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 },
{ 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 }
};
/************************ Global function definitions *************************/
/*******************************************************************************
* Delay in while loop cycles *
* Parameter: cnt: number of while cycles to delay *
* Return: *
*******************************************************************************/
static void delay (int cnt)
{
cnt <<= DELAY_2N;
while (cnt--);
}
/*******************************************************************************
* Read status of LCD controller *
* Parameter: none *
* Return: Status byte contains busy flag and address pointer *
*******************************************************************************/
static unsigned char lcd_read_status (void)
{
unsigned char status;
LCD_DATA_DIR_IN
LCD_RS(0)
LCD_RW(1)
delay(10);
LCD_E(1)
delay(10);
status = LCD_DATA_IN << 4;
LCD_E(0)
delay(10);
LCD_E(1)
delay(10);
status |= LCD_DATA_IN;
LCD_E(0)
LCD_DATA_DIR_OUT
return (status);
}
/*******************************************************************************
* Wait until LCD controller busy flag is 0 *
* Parameter: *
* Return: Status byte of LCD controller (busy + address) *
*******************************************************************************/
static unsigned char wait_while_busy (void)
{
unsigned char status;
do {
status = lcd_read_status();
} while (status & 0x80); /* Wait for busy flag */
return (status);
}
/*******************************************************************************
* Write 4-bits to LCD controller *
* Parameter: c: command to be written *
* Return: *
*******************************************************************************/
void lcd_write_4bit (unsigned char c)
{
LCD_RW(0)
LCD_E(1)
LCD_DATA_OUT(c&0x0F)
delay(10);
LCD_E(0)
delay(10);
}
/*******************************************************************************
* Write command to LCD controller *
* Parameter: c: command to be written *
* Return: *
*******************************************************************************/
void lcd_write_cmd (unsigned char c)
{
wait_while_busy();
LCD_RS(0)
lcd_write_4bit (c>>4);
lcd_write_4bit (c);
}
/*******************************************************************************
* Write data to LCD controller *
* Parameter: c: data to be written *
* Return: *
*******************************************************************************/
static void lcd_write_data (unsigned char c)
{
wait_while_busy();
LCD_RS(1)
lcd_write_4bit (c>>4);
lcd_write_4bit (c);
}
/*******************************************************************************
* Print Character to current cursor position *
* Parameter: c: character to be printed *
* Return: *
*******************************************************************************/
void lcd_putchar (char c)
{
lcd_write_data (c);
}
/*******************************************************************************
* Initialize the LCD controller *
* Parameter: *
* Return: *
*******************************************************************************/
void lcd_init (void)
{
int i;
unsigned char const *p;
/* Set all pins for LCD as outputs */
LCD_ALL_DIR_OUT
delay (15000);
LCD_RS(0)
lcd_write_4bit (0x3); /* Select 4-bit interface */
delay (4100);
lcd_write_4bit (0x3);
delay (100);
lcd_write_4bit (0x3);
lcd_write_4bit (0x2);
lcd_write_cmd (0x28); /* 2 lines, 5x8 character matrix */
lcd_write_cmd (0x0C); /* Display ctrl:Disp=ON,Curs/Blnk=OFF */
lcd_write_cmd (0x06); /* Entry mode: Move right, no shift */
/* Load user-specific characters into CGRAM */
lcd_write_cmd(0x40); /* Set CGRAM address counter to 0 */
p = &UserFont[0][0];
for (i = 0; i < sizeof(UserFont); i++, p++)
lcd_putchar (*p);
lcd_write_cmd(0x80); /* Set DDRAM address counter to 0 */
}
/*******************************************************************************
* Set cursor position on LCD display *
* Parameter: column: column position *
* line: line position *
* Return: *
*******************************************************************************/
void set_cursor (unsigned char column, unsigned char line)
{
unsigned char address;
address = (line * 40) + column;
address = 0x80 + (address & 0x7F);
lcd_write_cmd(address); /* Set DDRAM address counter to 0 */
}
/*******************************************************************************
* Clear the LCD display *
* Parameter: *
* Return: *
*******************************************************************************/
void lcd_clear (void)
{
lcd_write_cmd(0x01); /* Display clear */
set_cursor (0, 0);
}
/*******************************************************************************
* Print sting to LCD display *
* Parameter: string: pointer to output string *
* Return: *
*******************************************************************************/
void lcd_print (unsigned char const *string)
{
while (*string) {
lcd_putchar (*string++);
}
}
/******************************************************************************/
?? 快捷鍵說明
復制代碼
Ctrl + C
搜索代碼
Ctrl + F
全屏模式
F11
切換主題
Ctrl + Shift + D
顯示快捷鍵
?
增大字號
Ctrl + =
減小字號
Ctrl + -