ErrorStatus status;
for(;;)
{
status = BSP_I2C_IsDeviceReady(lcd_addr, 5000);
if(status == SUCCESS)
{
break;
}
}
uint8_t up = data & 0xF0;
uint8_t lo = (data << 4) & 0xF0;
uint8_t data_arr[4];
data_arr[0] = up|flags|BACKLIGHT|PIN_EN;
data_arr[1] = up|flags|BACKLIGHT;
data_arr[2] = lo|flags|BACKLIGHT|PIN_EN;
data_arr[3] = lo|flags|BACKLIGHT;
status = BSP_I2C_MasterTransmit(lcd_addr, data_arr, sizeof(data_arr), 5000);
LL_mDelay(LCD1602_DELAY);
return status;
}
void LCD_SendCommand(uint8_t lcd_addr, uint8_t cmd)
{
LCD_SendInternal(lcd_addr, cmd, 0);
}
void LCD_SendData(uint8_t lcd_addr, uint8_t data)
{
LCD_SendInternal(lcd_addr, data, PIN_RS);
}
void LCD_SendString(uint8_t lcd_addr, char *str)
{
while (*str)
{
LCD_SendData(lcd_addr, (uint8_t)(*str));
str++;
}
}
初始化设置
void LCD_Init(uint8_t lcd_addr)
{
// need at least 40ms after power rises above 2.7V
LL_mDelay(50);
// start in 8-bit mode, 3 commands
LCD_SendCommand(lcd_addr, LCD1602_CMD_FUNC_8B_1L_5X8);
LCD_SendCommand(lcd_addr, LCD1602_CMD_FUNC_8B_1L_5X8);
LCD_SendCommand(lcd_addr, LCD1602_CMD_FUNC_8B_1L_5X8);
// set it to 4-bit mode, interface is still 8-bit
LCD_SendCommand(lcd_addr, LCD1602_CMD_FUNC_4B_1L_5X8);
// now interface is 4-bit, set it to 2 lines and 5x8 font
LCD_SendCommand(lcd_addr, LCD1602_CMD_FUNC_4B_2L_5X8);
// display & cursor home
LCD_SendCommand(lcd_addr, LCD1602_CMD_HOME);
// display on, right shift, underline off, blink off
LCD_SendCommand(lcd_addr, LCD1602_CMD_MODE_ON_CURSOR_BLNK);
// move direction right
LCD_SendCommand(lcd_addr, LCD1602_CMD_DIRECTION_RIGHT);
// clear display (optional here)
LCD_SendCommand(lcd_addr, LCD1602_CMD_CLEAR_DISPLAY);
}
功能操作
清除屏幕
LCD_SendCommand(LCD1602_I2C_ADDR, LCD1602_CMD_CLEAR_DISPLAY);
移动光标, 输出文字
// move cursor to 0,0
LCD_SendCommand(LCD1602_I2C_ADDR, LCD1602_DDRAM_ROW0|0);
LCD_SendString(LCD1602_I2C_ADDR, " Using 1602 LCD");
// move cursor to 1,0
LCD_SendCommand(LCD1602_I2C_ADDR, LCD1602_DDRAM_ROW1|0);
LCD_SendString(LCD1602_I2C_ADDR, " over I2C bus");
通过 CGRAM 设置 自定义字符
// CGRAM test
for (i = 0; i < 8; i++)
{
LCD_SetCGRAM(LCD1602_I2C_ADDR, i, &cgrom[i * 8]);
}
展示自定义字符
for (i = 0; i < 8; i++)
{
LCD_SendData(LCD1602_I2C_ADDR, i);
LL_mDelay(200);
}
显示整体左右平移
// Shift display test
LCD_SendCommand(LCD1602_I2C_ADDR, LCD1602_CMD_CLEAR_DISPLAY);
LL_mDelay(500);
LCD_SendCommand(LCD1602_I2C_ADDR, LCD1602_DDRAM_ROW0|9);
LCD_SendString(LCD1602_I2C_ADDR, "Shift");
LCD_SendCommand(LCD1602_I2C_ADDR, LCD1602_DDRAM_ROW1|8);
LCD_SendString(LCD1602_I2C_ADDR, "<<<->>>");
LL_mDelay(500);
for (i = 0; i < 8; i++)
{
LCD_SendCommand(LCD1602_I2C_ADDR, LCD1602_CMD_DISPLAY_SHIFT_LEFT);
LL_mDelay(200);
}
LL_mDelay(500);
for (i = 0; i < 8; i++)
{
LCD_SendCommand(LCD1602_I2C_ADDR, LCD1602_CMD_DISPLAY_SHIFT_RIGHT);
LL_mDelay(200);
}
左右移动光标
// Move cursor test
for (i = 0; i < 11; i++)
{
LCD_SendCommand(LCD1602_I2C_ADDR, LCD1602_CMD_CURSOR_MOVE_LEFT);
LL_mDelay(200);
}
LL_mDelay(500);
for (i = 0; i < 12; i++)
{
LCD_SendCommand(LCD1602_I2C_ADDR, LCD1602_CMD_CURSOR_MOVE_RIGHT);
LL_mDelay(200);
}
常见问题
1. 屏幕不显示
不显示的原因有很多, 如果确认代码和接线无误, 可能的原因有
- 检查1602LCD的供电电压是不是5V, 在3.3V下无法驱动,