LCD defines?

Im using a PIC18F252 with a 16x2 LCD with a 44780 controller and I cant get LCDOut to work. I just get a row of black boxes on the second line of the LCD. Ive been using the basic MicroCode Studio example for an LCD display:

' LCD should be connected as follows:
' LCD PIC
' DB4 PortA.0
' DB5 PortA.1
' DB6 PortA.2
' DB7 PortA.3
' RS PortA.4 (add 4.7K pullup resistor to 5 volts)
' E PortB.3
' RW Ground
' Vdd 5 volts
' Vss Ground
' Vo 20K potentiometer (or ground)
' DB0-3 No connect

@ __CONFIG _CONFIG1H, _OSCS_OFF_1H & _HS_OSC_1H
@ __CONFIG _CONFIG2H, _WDT_OFF_2H & _WDTPS_128_2H
@ __CONFIG _CONFIG4L, _LVP_OFF_4L

Pause 500 ' Wait for LCD to startup
loop:
Lcdout $fe, 1 ' Clear LCD screen
Lcdout "Hello" ' Display Hello
Pause 500 ' Wait .5 second

Lcdout $fe, 1 ' Clear LCD screen
Lcdout "World"
Pause 500 ' Wait .5 second

Goto loop ' Do it forever

But it does not work. Do I need to define a bunch of "LCD_xxxx" things?

Turn off A/D on portA.

ADCON1 = 7

I added ADCON1 = 7 right after I define OSC, but I still get the same results.

you'll have to use those define to change PBP defaults.

Code:

---

@ __CONFIG _CONFIG1H, _OSCS_OFF_1H & _HS_OSC_1H
@ __CONFIG _CONFIG2H, _WDT_OFF_2H & _WDTPS_128_2H
@ __CONFIG _CONFIG4L, _LVP_OFF_4L

' LCD should be connected as follows:
' LCD PIC
' DB4 PortA.0
' DB5 PortA.1
' DB6 PortA.2
' DB7 PortA.3
' RS PortA.4 (add 4.7K pullup resistor to 5 volts)
' E PortB.3
' RW Ground
' Vdd 5 volts
' Vss Ground
' Vo 20K potentiometer (or ground)
' DB0-3 No connect

DEFINE LCD_DREG PORTA
DEFINE LCD_DBIT 0
DEFINE LCD_RSREG PORTA
DEFINE LCD_RSBIT 4
DEFINE LCD_EREG PORTB
DEFINE LCD_EBIT 3
ADCON1=7

---

AND SINCE you use HS osc you'll have to add

Define OSC 20
or the right crystal speed at the top of your code under the fuse setting

Still not working. I have a 10 MHz resonator, so I added Define OSC 10 under the fuses. My code is now:

'@ INCLUDE "P18F252.INC" ; MPASM Header
@ __CONFIG _CONFIG1H, _OSCS_OFF_1H & _HS_OSC_1H
@ __CONFIG _CONFIG2H, _WDT_OFF_2H & _WDTPS_128_2H
@ __CONFIG _CONFIG4L, _LVP_OFF_4L
Define OSC 10

DEFINE LCD_DREG PORTA
DEFINE LCD_DBIT 0
DEFINE LCD_RSREG PORTA
DEFINE LCD_RSBIT 4
DEFINE LCD_EREG PORTB
DEFINE LCD_EBIT 3
ADCON1=7

Pause 500 ' Wait for LCD to startup

loop:
Lcdout $fe, 1 ' Clear LCD screen
Lcdout "Hello" ' Display Hello
Pause 500 ' Wait .5 second

Lcdout $fe, 1 ' Clear LCD screen
Lcdout "World"
Pause 500 ' Wait .5 second

Goto loop ' Do it forever

Try this;

Code:

---

@ __CONFIG _CONFIG1H, _OSCS_OFF_1H & _HS_OSC_1H
@ __CONFIG _CONFIG2H, _WDT_OFF_2H & _WDTPS_128_2H
@ __CONFIG _CONFIG4L, _LVP_OFF_4L

Define OSC 20 ' change to osc freq you use if different
Define LCD_BITS 4  ' 4-bit interface
Define LCD_LINES 2 ' 2 line LCD

' LCD should be connected as follows:
' LCD PIC
' DB4 PortA.0
' DB5 PortA.1
' DB6 PortA.2
' DB7 PortA.3
Define  LCD_DREG  PORTA
Define  LCD_DBIT  0

' RS PortA.4 (add 4.7K pullup resistor to 5 volts)
Define  LCD_RSREG  PORTA
Define  LCD_RSBIT  4

' E PortB.3
Define  LCD_EREG  PORTB
Define  LCD_EBIT  3

' RW Ground
' Vdd 5 volts
' Vss Ground
' Vo 20K potentiometer (wire wiper to Vo, adjust for contrast)
' DB0-3 No connect

Define LCD_COMMANDUS  2000 ' Adjust for slower LCD modules
Define LCD_DATAUS 50

ADCON1 = 7 ' portA digital

Pause 500 ' Wait for LCD to startup
loop:
    Lcdout $fe, 1 ' Clear LCD screen
    Lcdout "Hello" ' Display Hello
    Pause 500 ' Wait .5 second

    Lcdout $fe, 1 ' Clear LCD screen
    Lcdout "World"
    Pause 500 ' Wait .5 second

    Goto loop ' Do it forever

---

I tried that code and I still only see the black boxes on the second row. Im going to check all of the connections and try a potentiometor on Vo

Edit:

The connections are all good and my contrast is fine without a potentiometor. I think my LCD might be dead, but Im not sure because the backlight works and I can see the boxes it displays.

out of curiosity...
what kind of programmer do you use?
Are you sure your programmer software program the fuses to the PIC?

And... of course, is a simple LED blink work on all the pin you use???

Im using a JDM programmer (the one called "Serial Port Programmer - Socketed" at http://www.sparkfun.com/shop/index.p...=323317&cat=3&) and IC-Prog as my downloading program. I just tested the IO lines and they all work.

I have also tried the program on another PIC18F252 and I get the same results.

EDIT:

The LCDOut command is for 44780 controllers right??

RUBiksCUbe, If I may ask, What type of LCD display is it? Who makes it? Part number?

Dave Purola,
N8NTA

I Noticed that your comment was the black squares were on the second line... I also noticed the examples presented looked like they were all for the first line of your LCD.

1. Since you only have 1 line of squares on your LCD, then I would suspect your line 1 is bad... test another LCD.

2. If you want, try writing to your second line on your LCD...

I believe the command is a $C0?

Somthing like :
LCDOUT $FE,$C0,“Hello”

If this works on your second line... then you may have found your problem.

Dwayne

The LCD is a 16 character by 2 line display. Although it says "UNIQ/eVision" on the back, it has the part number GC-1602I1 Ver: C, which is a part number for Solomon Goldentek display company. They don't have the exact datasheet on their website, but the closest one they have is here: http://www.goldentek.com/english/pdf...B0SBL1B%20.pdf

I was told when I bought it (on ebay) that the display driver is 44780 compatible.

I put the LCDOUT $FE,$C0,“Hello” into the program but it did not work either. This LCD must be busted.

They use samsung controller KS0066 wich is really compatible with Hitachi, in fact i have some LCD here with the same controller and i used the same code... as is and it's work...mmm weird

Yuk, probably not really handy but, worth a try...

Code:

---

@ __CONFIG _CONFIG1H, _OSCS_OFF_1H & _HS_OSC_1H
@ __CONFIG _CONFIG2H, _WDT_OFF_2H & _WDTPS_128_2H
@ __CONFIG _CONFIG4L, _LVP_OFF_4L

Define OSC 10

TRISA=0
TRISB=0
Define LCD_BITS 4  ' 4-bit interface
Define LCD_LINES 2 ' 2 line LCD

' LCD should be connected as follows:
' LCD PIC
' DB4 PortA.0
' DB5 PortA.1
' DB6 PortA.2
' DB7 PortA.3
Define  LCD_DREG  PORTA
Define  LCD_DBIT  0

' RS PortA.4 (add 4.7K pullup resistor to 5 volts)
Define  LCD_RSREG  PORTA
Define  LCD_RSBIT  4

' E PortB.3
Define  LCD_EREG  PORTB
Define  LCD_EBIT  3

' RW Ground
' Vdd 5 volts
' Vss Ground
' Vo 20K potentiometer (wire wiper to Vo, adjust for contrast)
' DB0-3 No connect

Define LCD_COMMANDUS  2000 ' Adjust for slower LCD modules
Define LCD_DATAUS 50

ADCON1 = 7 ' portA digital
Pause 1000
FLAGS=0
Pause 1000
loop:
    Lcdout $fe, 1,"Hello"
    Pause 500 ' Wait .5 second

    Lcdout $fe, 1,"World"
    Pause 500 ' Wait .5 second

    Goto loop ' Do it forever

---

I heard few time, but never encouter the problem, that some LCDs are noise sensitive, what about if you add a 0.1uF and a 10uF(or higher) on the VDD line close to the LCD(as close as you can)???

Now if nothing works... it could be a blowed one... On EBay... not a surprise ;)

I tried capacitors with no success, so Im going to try to get another. Thanks for all the diagnostic help!

Hello RUBiksCUbe,

I have just bought the same display as you and I was searching the net for datasheet and found this page.

I have not received this display and I hope I will get it working.
But it doesnt sound good to read your problem.

I hope to get it in a week or two, then I will test it and come back to you guys.

Good luck now...

I have tested same display...
WORKING GREAT!

Yep. I got a replacement and it worked fine. I mustve had a defective one

Hi,
Most of the intellegent LCD displays are very sensitive to static.
They are the only components I've used were I've had failures directly attributable it ESD.

Robert G8RPI.