Hi people :)

I am sure this has already been addressed by the forum, but I had no luck in
searching this specific problem.

I purchased a 2x16 LCD with an Hitachi HD44780 controller. I am using a 4
bit interface, with a pickit 2 low count demo board.

I soldered db4-7 into Rb4-7

Read Write Select into GROUND

ReadWrite enable into RC6
Register Select RC7

So I am using 6 pins of my 16F690 for data and signaling. I am also turning
on and off portc.1, hooked into a LED in the lowcount demoboard, in order to
visually confirm that my loop is going ok.

I send a clear LCD command and try to get "hello" and later a "world" out,
in a loop with .5 secs delay. =


All I can see is the first LCD line powered up, and full black boxes that
turn on, filling eventually the first lcd line. No second line, no text, No
clear LCD command. The black boxes turn on instead "hello" and world"
(timing and chars quantity are ok)

I=B4ve been asking around and it seems that although it may be possible to
communicate with 4 bits to the LCD, I need more bits in order to signal some
commands ?

Example: Telling the Hitachi 44780 to use 2 lines: I am looking into =


http://home.iae.nl/users/pouweha/lcd/lcd0.shtml#instruction_set

and I cannot see an explanation about how does this get translated in a 4
bit environment, if it can be done at all. =


Do I need to connect the 8 bits from the pic into the LCD interfase ?

Is my LCD broken ?

In order to speed up coding, I am using picbasic pro:

ANSEL=3D0
ANSELH=3D0
trisb=3D0
trisc=3D0
portb=3D0
portc=3D0

DEFINE LCD_DREG PORTB
DEFINE LCD_BIT 4

DEFINE LCD_RSREG PORTC
DEFINE LCD_RSBIT 7

DEFINE LCD_EREG PORTC
DEFINE LCD_EBIT 6

DEFINE LCD_BITS 4
DEFINE LCD_LINES 2

DEFINE LCD_COMMANDUS 2000
DEFINE LCD_DATAUS 50

LED1 VAR PORTC.1

pause 1000

loop:   lcdout $fe,1  ' Clear LCD screen
        Lcdout $fe,"Hello"  ' Display Hello
	high led1
        Pause 500       ' Wait .5 second
        lcdout $fe,1   ' Clear LCD screen
        Lcdout $fe,"World"
	low led1
        Pause 500       ' Wait .5 second
        Goto loop       ' Do it forever
end



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