4 bit mode of PIC to LCD intefacing

lcd 4 bit mode

Hi, I have quetion about The PIC to LCD interfacing in 4 bit mode,
If I use the equivalent of the HD447780 LCD module to PIC16F84A interfacing in 4 bit mode(there are DB4-DB7 connect to the pins of PIC) and I use the PICbasic Compiler , Do I must be setting the software/program for this purpose or this way is enough? (I read from a paper that something must be set in that program because the default of the LCD module is 8 bit mode, but it was'nt explained). Please, somebody help me.

hd447780

hi

you need to tell picbasic that you are using a 4bit interface.

for more information about picbasic you can check the forum at:

picbasic.co.uk

its a great site dedicated for picbasic users.


best regards
ferds

ks0066 pic

Go to this link for detail

https://www.myke.com/lcd.htm

programming pic 4 bit mode

Look at datasheet below, mainly in page 26. It's give the procedures for initialization in a 4 bits mode. But for LCDs works well, you have to send a nibble (with 0x3) value, three times, before you send commands request on page 26 of datasheet.

Example:

bit_clear(RS); // RS = 0;
delay(d100us);
bit_clear(RW); // RW = 0;
delay(d100us);
bit_set(ENABLE); // E = 1;

delay(d50ms);
for(i=1;i<=3;++i)
{
lcd_send_nibble(3); // Send it 3 times
delay(d5ms);
}

// Here start datasheet procedures
lcd_send_nibble(2);
delay(d5ms);


// 1º byte FUNCTION SET
lcd_send_byte(0,0x28); // 0 0 1 DL N F X X

delay(d5ms); // consta no datasheet KS0066 da Samsung

// 2º byte DISPLAY ON/OFF CONTROL
lcd_send_byte(0,0x0F); // 0 0 0 0 1 D C B

delay(d5ms); // consta no datasheet KS0066 da Samsung

// 3º byte Display Clear
lcd_send_byte(0,0x01); // 0 0 0 0 0 0 0 1

delay(d5ms); // consta no datasheet KS0066 da Samsung

// 4º byte Entry Mode Set
lcd_send_byte(0,0x0C); // 0 0 0 0 0 1 I/D SH

ks0066 samsung

Se also HD44780