CCS :: View topic - 16f876 and lcd

CCS C Software and Maintenance Offers

FAQ

Official CCS Support

Profile Log in to check your private messages Log in

CCS does not monitor this forum on a regular basis.

Please do not post bug reports on this forum. Send them to support@ccsinfo.com

CCS Forum Index -> General CCS C Discussion

View previous topic :: View next topic

Author

Message

adalucio

Joined: 16 Mar 2009
Posts: 29

16f876 and lcd

Posted: Mon May 09, 2011 12:11 pm

Reply with quote

Hi all

I'm trying to use a (working) lcd (20x2) with a 16f876. I have a 20Mhz quartz.

I see only the first line with all square.

DB4 - RA2
DB5 - RA0
DB6 - RA1
DB7 - RA4
RS - RB6
RW - RA3
E - RB7

main.c

Code:

#include <main.h>
#include "flex_lcd_16x1.c"

void main()
{
setup_adc_ports(NO_ANALOGS);
setup_adc(ADC_OFF);

delay_ms(100);
lcd_init();
delay_ms(600);

printf(lcd_putc, "\fABCDEFGHIJKLMNOPQRST");
printf(lcd_putc, "\nabcdefghijklmnopqrst");

delay_ms(2000);

while(1)
{
output_high(PIN_B0);
delay_ms(1000);
output_low(PIN_B0);
delay_ms(1000);

printf(lcd_putc, "Test");
}
}

main.h

Code:

#include <16F876.h>

#FUSES NOWDT //No Watch Dog Timer
#FUSES HS //Crystal osc <= 4mhz for PCM/PCH , 3mhz to 10 mhz for PCD
#FUSES PUT //Power Up Timer
#FUSES NOBROWNOUT //No brownout reset
#FUSES NOLVP //No low voltage prgming, B3(PIC16) or B5(PIC18) used for I/O
#FUSES NOCPD //No EE protection
#FUSES NOWRT //Program memory not write protected
#FUSES NODEBUG //No Debug mode for ICD
#FUSES NOPROTECT //Code not protected from reading

#use delay(clock=20000000)

Code:

#define LCD_DB4 PIN_A2
#define LCD_DB5 PIN_A0
#define LCD_DB6 PIN_A1
#define LCD_DB7 PIN_A4

#define LCD_RS PIN_B6
#define LCD_RW PIN_A3
#define LCD_E PIN_B7

Thanks

PCM programmer

Joined: 06 Sep 2003
Posts: 21708

Posted: Mon May 09, 2011 12:17 pm

Reply with quote

Quote:

DB4 - RA2
DB5 - RA0
DB6 - RA1
DB7 - RA4
RS - RB6
RW - RA3
E - RB7

Pin A4 is open-drain on this PIC. It needs an external 4.7K pull-up
resistor on that pin, to operate as an output pin. The LCD has a pull-up
on the DB7 pin, but it's very weak. You should add the external 4.7K
pull-up to it.

Also, you're using pins B6 and B7 for the lcd. Those are the programmer
and debugger pins (for ICD2, ICD3, PicKit, ICD-U40, etc.). The lcd
won't run if the ICD is connected to the board. It's better if you use two
other pins for the lcd.

Quote:

I'm trying to use a (working) lcd (20x2) with a 16f876.
#include "flex_lcd_16x1.c"

Also, you are using the wrong Flex driver. You have a 2-line LCD.
I think the 16x2 Flex driver would work OK for your LCD:
http://www.ccsinfo.com/forum/viewtopic.php?t=24661

adalucio

Joined: 16 Mar 2009
Posts: 29


Posted: Tue May 10, 2011 2:11 am

Thanks it worked

Display posts from previous:

	CCS Forum Index -> General CCS C Discussion	All times are GMT - 6 Hours
Page 1 of 1

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

Powered by phpBB © 2001, 2005 phpBB Group