4-bit Initialization:
/**********************************************************/
void command(char i)
{
P1 = i;
D_I =0;
R_W =0;
//put data on output Port
//D/I=LOW : send instruction
//R/W=LOW : Write
Nybble();
i = i<<4;
P1 = i;
//Send lower 4 bits
//Shift over by 4 bits
//put data on output Port
//Send upper 4 bits
Nybble();
}
/**********************************************************/
void write(char i)
{
P1 = i;
D_I =1;
R_W =0;
//put data on output Port
//D/I=HIGH : send data
//R/W=LOW : Write
Nybble();
i = i<<4;
P1 = i;
//Clock lower 4 bits
//Shift over by 4 bits
//put data on output Port
//Clock upper 4 bits
Nybble();
}
/**********************************************************/
void Nybble()
{
E = 1;
Delay(1);
E = 0;
//enable pulse width >= 300ns
//Clock enable: falling edge
}
/**********************************************************/
void init()
{
P1 = 0;
P3 = 0;
Delay(100);
P1 = 0x30;
Delay(30);
Nybble();
//Wait >15 msec after power is applied
//put 0x30 on the output port
//must wait 5ms, busy flag not available
//command 0x30 = Wake up
Delay(10);
Nybble();
Delay(10);
Nybble();
//must wait 160us, busy flag not available
//command 0x30 = Wake up #2
//must wait 160us, busy flag not available
//command 0x30 = Wake up #3
Delay(10);
P1= 0x20;
Nybble();
command(0x28);
command(0x10);
command(0x0F);
command(0x06);
//can check busy flag now instead of delay
//put 0x20 on the output port
//Function set: 4-bit interface
//Function set: 4-bit/2-line
//Set cursor
//Display ON; Blinking cursor
//Entry Mode set
}
[11]
NEWHAVEN [ NEWHAVEN DISPLAY INTERNATIONAL, INC. ]
