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|
#include "project.h"
#ifndef SLIM
#define FOO do { printf("lcd:%x\r\n",__LINE__); usart1_drain(); } while (0)
#define PCF8574_I2C_ADDRESS 0x27
#define LINE_RS 0x1
#define LINE_RnW 0x2
#define LINE_EN 0x4
#define LINE_BACKLIGHT 0x8
#define LCD_CLEAR 0x1
#define LCD_HOME 0x2
#define LCD_DISP 0x8
#define LCD_DISP_ON 0x4
#define LCD_DISP_CURSOR 0x2
#define LCD_DISP_CURSOR_BLINK 0x1
#define LCD_FUNC 0x20
#define LCD_FUNC_8BIT 0x10
#define LCD_FUNC_4BIT 0x00
#define LCD_FUNC_2ROWS 0x08
#define LCD_FUNC_1ROW 0x00
#define LCD_FUNC_5x10 0x04
#define LCD_FUNC_5X7 0x00
#define LCD_SET_DDRAM_ADDR 0x80
#define LCD_H_SHIFT 5
#define LCD_RS (1 << LCD_H_SHIFT)
#define LCD_W 16
#define LCD_W_MASK (LCD_RS -1 )
#define LCD_H 2
#define LCD_SZ (LCD_H << LCD_H_SHIFT)
#define LCD_POS(c,r) (((r) << LCD_H_SHIFT ) +(c))
#define BYTES_PER_BYTE 6
#define DMA_BUF_SZ (BYTES_PER_BYTE * ( (1 + LCD_W) *LCD_H + 1))
static int backlight;
uint8_t fb[LCD_H][LCD_W];
uint8_t shadow[LCD_H][LCD_W];
static int pos;
static void
clock_nibble (uint8_t n)
{
if (backlight)
n |= LINE_BACKLIGHT;
i2c_bb_send_data (n);
i2c_bb_send_data (LINE_EN | n);
i2c_bb_send_data (n);
}
static void
write_reg (uint8_t c, int r)
{
uint8_t b;
b = c & 0xf0;
if (r)
b |= LINE_RS;
clock_nibble (b);
b = (c & 0xf) << 4;
if (r)
b |= LINE_RS;
clock_nibble (b);
}
static void
send_data (uint8_t c)
{
write_reg (c, 1);
}
static void
send_command (uint8_t c)
{
write_reg (c, 0);
}
static void
send_one_command (uint8_t cmd, int delay)
{
i2c_bb_start_transaction (PCF8574_I2C_ADDRESS, I2C_WRITE);
send_command (cmd);
i2c_bb_stop ();
if (delay)
delay_ms (delay);
}
static void
cls (void)
{
send_one_command (LCD_CLEAR, 2);
}
#if 0
static void
home (void)
{
send_one_command (LCD_HOME, 2);
}
#endif
static void
on (void)
{
send_one_command (LCD_DISP | LCD_DISP_ON /* | LCD_DISP_CURSOR */ , 4);
}
static void
off (void)
{
send_one_command (LCD_DISP, 4);
}
static int
lcd_addr (int x, int y)
{
return x + ((y & 1) << 6) + ((y & 2) ? 20 : 0);
}
#if 0
static void
move (uint8_t c, uint8_t r)
{
send_one_command (LCD_SET_DDRAM_ADDR | lcd_addr (c, r), 2);
}
#endif
void
lcd_refresh (void)
{
int c, r;
int addr;
i2c_bb_start_transaction (PCF8574_I2C_ADDRESS, I2C_WRITE);
for (r = 0; r < LCD_H; ++r)
{
for (c = 0; c < LCD_W; ++c)
{
if (shadow[r][c] != fb[r][c])
{
addr = lcd_addr (c, r);
if (addr != pos)
{
send_command (LCD_SET_DDRAM_ADDR | addr);
pos = addr;
}
send_data (shadow[r][c]);
fb[r][c] = shadow[r][c];
pos++;
}
}
}
i2c_bb_stop ();
}
void
lcd_tick (void)
{
static int u;
u++;
if (u < 100)
return;
u = 0;
if (!memcmp (shadow, fb, sizeof (fb)))
return;
lcd_refresh ();
}
void
lcd_write_char (uint8_t c, int x, int y)
{
shadow[y][x] = c;
}
void
lcd_erase (int x, int y, int w)
{
uint8_t *ptr = &shadow[y][x];
while (w--)
*ptr = ' ';
}
void
lcd_erase_line (int w, int y)
{
lcd_erase (0, y, w);
}
void
lcd_erase_all (void)
{
int y;
for (y = 0; y < LCD_H; ++y)
{
lcd_erase (0, 0, LCD_W);
}
}
void
lcd_write (char *c, int x, int y)
{
while (*c)
{
lcd_write_char (*(c++), x++, y);
if (x == LCD_W)
break;
}
}
#if 0
static void
lcd_scroll (uint8_t * p)
{
int i;
for (i = 0; i < 3; ++i)
{
memcpy (p, p + LCD_RS, LCD_W);
p += LCD_RS;
}
memset (p, ' ', LCD_W);
}
void
lcd_putc (uint8_t c)
{
switch (c)
{
case '\r':
pos &= ~LCD_W_MASK;
break;
case '\n':
pos &= ~LCD_W_MASK;
pos += LCD_RS;
break;
default:
buf[pos] = c;
pos++;
}
if ((pos & LCD_W_MASK) == LCD_W)
{
pos &= ~LCD_W_MASK;
pos += LCD_RS;
}
if (pos == LCD_SZ)
{
lcd_scroll (buf);
pos -= LCD_RS;
}
}
#endif
void
lcd_backlight (int i)
{
backlight = i;
i2c_bb_start_transaction (PCF8574_I2C_ADDRESS, I2C_WRITE);
i2c_bb_send_data (backlight ? LINE_BACKLIGHT : 0);
i2c_bb_stop ();
}
void
lcd_reset (void)
{
i2c_bb_start_transaction (PCF8574_I2C_ADDRESS, I2C_WRITE);
clock_nibble (0x30);
delay_ms (5);
clock_nibble (0x30);
delay_us (64);
clock_nibble (0x30);
delay_us (64);
clock_nibble (0x20);
send_command (LCD_FUNC | LCD_FUNC_4BIT | LCD_FUNC_2ROWS | LCD_FUNC_5X7);
i2c_bb_stop ();
on ();
cls ();
}
void
lcd_init (void)
{
lcd_backlight (0);
lcd_reset ();
lcd_backlight (1);
}
void
lcd_shutdown (void)
{
lcd_backlight (0);
off ();
}
#endif
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