/*!
* \brief Send half byte to LCD controller.
*
* \param nib The four least significant bits are sent.
*/
static void LcdWriteNibble(unsigned int nib)
{
#ifdef LCD_DATA_LSB
nib <<= LCD_DATA_LSB;
#else
{
unsigned int val = 0;
if (nib & 0x01) {
val |= LCD_D0;
}
if (nib & 0x02) {
val |= LCD_D1;
}
if (nib & 0x04) {
val |= LCD_D2;
}
if (nib & 0x08) {
val |= LCD_D3;
}
nib = val;
}
#endif
LcdSetBits(nib & LCD_DATA);
LcdClrBits(~nib & LCD_DATA);
/* Create Enable Pulse:
* For HD44780 Displays we need:
* Vcc = 5.0V -> PWeh >= 230ns
* Vcc = 3.3V -> PWeh >= 500ns
*/
LCD_EN_SET();
NutMicroDelay(LCD_SHORT_DELAY);
LCD_EN_CLR();
}
/*!
* \brief Send byte to LCD controller.
*
* \param data Byte to send.
*/
static void LcdWriteByte(unsigned int data)
{
/* If configured set RW low */
#ifdef LCD_RW_BIT
LCD_RW_CLR();
#endif
/* If using 4-bit access, write two nibbles now */
#ifdef LCD_IF_4BIT
LcdWriteNibble(data >> 4);
LcdNanoDelay(LCD_PW_EH);
LcdWriteNibble(data);
#else
/* else write one byte */
data <<= LCD_DATA_LSB;
LcdSetBits(data & LCD_DATA);
LcdClrBits(~data & LCD_DATA);
#endif
/* If configured, let the task sleep before next character */
#if defined(LCD_SLEEP_DLY)
NutSleep(1);
#else
/* or add a fixed delay and immediately process next char */
NutMicroDelay(LCD_E2E_DLY);
#endif
}
static int LcdInit(NUTDEVICE * dev)
{
LCD_RS_CLR();
LCD_RW_CLR();
LcdClrBits(LCD_DATA);
NutMicroDelay(30);
LCD_EN_CLR();
NutMicroDelay(30);
NutSleep(18);
/* This initialization will make sure, that the LCD is switched
* to 8-bit mode, no matter which mode we start from or we finally
* need.
*/
LcdWriteCmd(_BV(LCD_FUNCTION) | _BV(LCD_FUNCTION_8BIT));
NutSleep(16);
LcdWriteCmd(_BV(LCD_FUNCTION) | _BV(LCD_FUNCTION_8BIT));
NutSleep(4);
LcdWriteCmd(_BV(LCD_FUNCTION) | _BV(LCD_FUNCTION_8BIT));
NutSleep(2);
LcdWriteInstruction((_BV(LCD_FUNCTION)) | (_BV(LCD_FUNCTION_8BIT)) | (_BV(LCD_EXT)) , LCD_SHORT_DELAY);
/* Switch display and cursor off. */
LcdWriteNibble(_BV(LCD_ON_CTRL) >> 4);
LcdWriteNibble(_BV(LCD_ON_CTRL));
NutSleep(2);
/* Clear display. */
LcdClear();
/* Set entry mode. */
LcdWriteCmd(_BV(LCD_ENTRY_MODE) | _BV(LCD_ENTRY_INC));
/* Switch display on. */
LcdWriteCmd(_BV(LCD_ON_CTRL) | _BV(LCD_ON_DISPLAY));
/* Move cursor home. */
LcdCursorHome();
/* Set data address to zero. */
LcdWriteCmd(_BV(LCD_DDRAM));
return 0;
}
static int LcdInit(NUTDEVICE * dev)
{
#if defined(PMC_PCER)
outr(PMC_PCER, _BV(LCD_RS_PIO_ID) | _BV(LCD_EN_PIO_ID));
#endif
/* Initialize GPIO lines. */
#ifdef LCD_RW_BIT
outr(PMC_PCER, _BV(LCD_RW_PIO_ID));
LCD_RW_CLR();
#endif
#ifdef LCD_EN2_BIT
outr(PMC_PCER, _BV(LCD_EN2_PIO_ID));
LCD_EN2_CLR();
#endif
#ifdef LCD_RST_BIT
outr(PMC_PCER, _BV(LCD_RST_PIO_ID));
LCD_RST_CLR();
#endif
LCD_RS_CLR();
LCD_RW_CLR();
LcdClrBits(LCD_DATA);
NutMicroDelay(30);
LCD_EN_CLR();
NutMicroDelay(30);
/* Initial delay. Actually only required after power on. */
NutSleep(16);
/* This initialization will make sure, that the LCD is switched
* to 8-bit mode, no matter which mode we start from or we finally
* need.
*/
LcdWriteNibble((_BV(LCD_FUNCTION) | _BV(LCD_FUNCTION_8BIT)) >> 4);
NutSleep(15);
LcdWriteNibble((_BV(LCD_FUNCTION) | _BV(LCD_FUNCTION_8BIT)) >> 4);
NutSleep(4);
LcdWriteNibble((_BV(LCD_FUNCTION) | _BV(LCD_FUNCTION_8BIT)) >> 4);
NutSleep(2);
#ifdef LCD_IF_4BIT
/* We now switch to 4-bit mode */
LcdWriteNibble(_BV(LCD_FUNCTION) >> 4);
NutSleep(2);
// TODO: Add support for large font in single line displays
/* Set number of lines and font. Can't be changed later. */
#if (LCD_ROWS == 2) || (LCD_ROWS==4)
LcdWriteNibble((_BV(LCD_FUNCTION) | _BV(LCD_FUNCTION_2LINES)) >> 4);
LcdWriteNibble(_BV(LCD_FUNCTION) | _BV(LCD_FUNCTION_2LINES));
#else
LcdWriteNibble(_BV(LCD_FUNCTION) >> 4);
LcdWriteNibble(_BV(LCD_FUNCTION) );
#endif
#else /* LCD_IF_4BIT */
LcdWriteCmd(_BV(LCD_FUNCTION) | _BV(LCD_FUNCTION_8BIT));
#endif /* LCD_IF_4BIT */
NutSleep(2);
/* Switch display and cursor off. */
LcdWriteNibble(_BV(LCD_ON_CTRL) >> 4);
LcdWriteNibble(_BV(LCD_ON_CTRL));
NutSleep(2);
/* Clear display. */
LcdClear();
/* Set entry mode. */
LcdWriteCmd(_BV(LCD_ENTRY_MODE) | _BV(LCD_ENTRY_INC));
/* Switch display on. */
LcdWriteCmd(_BV(LCD_ON_CTRL) | _BV(LCD_ON_DISPLAY));
/* Move cursor home. */
LcdCursorHome();
/* Set data address to zero. */
LcdWriteCmd(_BV(LCD_DDRAM));
return 0;
}
