/*!
* \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
}
