LCD - first line is black

[meme]

I have connected my LCD (KS0070B-00) at port B. The 3-rd pin (contrast) is connected through a variable resistor. I use the CCS drivers for LCD. In lcd.c I uncommented the define port B statement to use port B for the LCD. But when i try to write something on the lcd with the lcd_putc command, all I see is the first line black. Next is the code:

[treitmey]

Did you try adjusting the pot. (variable resister) that controls the contrast?

[meme]

yes. I adjusted the resistor untill the black line appeared. then I left it on the same position. when I try to send a character... nothing happens.
I connected pins 4 5 6 and 7 of portB with the pins DB4-DB7 of the LCD.

[Mark]

On a four line display, the first and third lines appear all black on power up. On a two line display, the top line will appear all black on power up.

That controller is compatiable with a HD44780 and it should work. How do you have it connected. Be specific.

What use delay value are you using?

[meme]

#use delay(clock=4000000)


connections are as follows:
pic16F877-A -> LCD
pinB0 -> E
pinB1 -> RS
pinB2 -> R/W
pinB3 -> not connected
pinB4 -> pin11
pinB5 -> pin12
pinB6 -> pin13
pinB7 -> pin14

the pins 15 and 16 of the LCD are not connected (as said in the datasheet)

[PCM programmer]

[meme]

thank you for the link but... it didn't help. or maybe I have to buy another type of LCD.

[Mark]

Does your LED blink?

[meme]

yes, the led is blinking as intended, but the lcd shows the first line filled, then both right halfs of the 2 lines filled. and then loops to the first line filled.

[behemoth]

I also have some problem with interfacing with LCD.
I manage with it by add additional delay before init_LCD command,like that:

#include <16f628A.h>
#fuses HS,NOWDT,PUT,NOPROTECT,NOBROWNOUT,NOLVP,MCLR,NOCPD
#use delay(clock=20000000)
#include <lcd.c>

#define LAMPKA PIN_A2
#define LAMPKA1 PIN_A3

main()
{
setup_adc_ports (NO_ANALOGS);

delay_ms(50);
lcd_init();

while(true)
{
output_high(LAMPKA);
output_low(LAMPKA1);
lcd_putc("\fkurcze-linia numer 1");
delay_ms(500);
output_low(LAMPKA);
lcd_putc("\f\nkurcze-linia numer 2-ok-");
output_high(LAMPKA1);
delay_ms(500);
}
}
After this everything started to work properly.

[behemoth]

I also have some problem with interfacing with LCD.
I manage with it by add additional delay before init_LCD command,like that:

#include <16f628A.h>
#fuses HS,NOWDT,PUT,NOPROTECT,NOBROWNOUT,NOLVP,MCLR,NOCPD
#use delay(clock=20000000)
#include <lcd.c>

#define LAMPKA PIN_A2
#define LAMPKA1 PIN_A3

main()
{
setup_adc_ports (NO_ANALOGS);

delay_ms(50);
lcd_init();

while(true)
{
output_high(LAMPKA);
output_low(LAMPKA1);
lcd_putc("\fkurcze-linia numer 1");
delay_ms(500);
output_low(LAMPKA);
lcd_putc("\f\nkurcze-linia numer 2-ok-");
output_high(LAMPKA1);
delay_ms(500);
}
}
After this everything started to work properly.