//*****************************************************************************
//
//! \brief Write data or command to the HD44780.
//!
//! \param ucRS determines if the IR or DR to select.
//!
//! The parameter of ucRS can be:
//! - HD44780_RS_COMMAND - select the IR.
//! - HD44780_RS_DATA - select the DR.
//!
//! \return None.
//
//*****************************************************************************
void
HD44780Write(unsigned char ucRS, unsigned char ucInstruction)
{
int i;
//
// Check Arguments.
//
xASSERT((ucRS == HD44780_RS_COMMAND) || (ucRS == HD44780_RS_DATA));
//
// RS:Command, RW:Write, E:Enable
//
_digitalWrite(ucRsPin, ucRS);
_digitalWrite(ucEnablePin, HD44780_E_ENABLE);
//
// Output Data
//
for ( i = 0; i < 4; i++)
{
_digitalWrite(ucDataPin[i], (ucInstruction >> (i+4)) & 0x01);
}
PulseEnable();
xSysCtlDelay(10);
_digitalWrite(ucEnablePin, HD44780_E_ENABLE);
for ( i = 0; i < 4; i++)
{
_digitalWrite(ucDataPin[i], (ucInstruction >> (i)) & 0x01);
}
xSysCtlDelay(10);
PulseEnable();
}
/*************************************************************************************
*
* Function: WriteLcdDataByte
*
* Description: Function used to split 8 bit commands into two 4 bit commands.
* Note: This can only be used after setting LCD module in 4 bit mode
*
* Parameters: byte: Byte value to trigger, Bank: Setting of RS bit
*
* Return: void
*
*************************************************************************************/
void WriteLcdDataByte(char byte, unsigned char Bank)
{
unsigned char highnib;
unsigned char lownib;
if(Bank == INSTRUCTION_REG)
{
lownib = (byte & 0x0F) << 4 | BL;
highnib = (byte & 0xF0) | BL;
}
if(Bank == DATA_REG)
{
lownib = (byte & 0x0F) << 4 | BL | RS;
highnib = (byte & 0xF0) | BL | RS;
}
/* First write the 4 MSB bits */
WriteByteI2C(highnib);
/* Trigger the data */
PulseEnable(highnib);
/* Now write the 4 LSB bits */
WriteByteI2C(lownib);
/* Trigger the data */
PulseEnable(lownib);
}
/*************************************************************************************
*
* Function: WriteLcdDataNibble
*
* Description: Function that writes only 4 bits to the LCD
*
* Parameters: Nibble value to trigger
*
* Return: void
*
*************************************************************************************/
void WriteLcdDataNibble(unsigned char nibble)
{
/* High nibble */
unsigned char nibble_val = (nibble & 0x0F) << 4 | BL;
/* Write the byte to I2C (nibble value in above 4 bits) */
WriteByteI2C(nibble_val);
/* Trigger the data */
PulseEnable(nibble_val);
}
