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karthi27
Joined: 18 Nov 2009
Posts: 10
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| Help needed regarding 2x16 JHD162A LCD and PIC16f877 code |
 Posted: Tue Dec 08, 2009 7:58 am |
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Hi 
I've been working with PIC16F877 and 2x16 JHD162A LCD module for the past 3 days. No success yet.
All that I get is black boxes in row one. And after sometime a portion of black boxes in row 2 is displayed and nothing else happens.
I monitored my EN bit, RS bit, RW bit and busy bit(DB7) with leds. Even the data bus. They are working fine. The PIC controller and ICD2 programmer are fine.
I suspect a bug in my program. Please help me identify the bug. Guess its in the initializing routine. Tried with various delay values. No success.
_________________
Regards
Karthi
Last edited by karthi27 on Thu Dec 17, 2009 11:29 pm; edited 1 time in total |
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anandpv2009
Joined: 26 Jul 2009
Posts: 31
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| Posted: Tue Dec 08, 2009 8:39 am |
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Use the following code
Code:
| Code: | #include<16f877a.h>
#USE delay(clock=4000000) //SETTING CLOCK FREQUENCY
#FUSES XT,NOWDT,NOBROWNOUT,NOPROTECT,NOPUT //SETTING FUSES
#include<lcd.c>
void main()
{
delay_ms(100);
lcd_init();
delay_ms(100);
printf(lcd_putc,"\fHello");
while(1);
} |
connection
//// #define LCD_ENABLE_PIN PIN_B0 ////
//// #define LCD_RS_PIN PIN_B1 ////
//// #define LCD_RW_PIN PIN_B2 ////
//// #define LCD_DATA4 PIN_B4 ////
//// #define LCD_DATA5 PIN_B5 ////
//// #define LCD_DATA6 PIN_B6 ////
//// #define LCD_DATA7 PIN_B7
There is no need to use 8 bit interfacing use 4 bit interfacing... |
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Tue Dec 08, 2009 3:52 pm |
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You're trying to write your own LCD driver, I assume in 8-bit mode.
You're sort of trying to re-invent the wheel. Most people won't be
interested in that. Nisar has posted an 8-bit driver here:
http://www.ccsinfo.com/forum/viewtopic.php?t=38367
I haven't tested it, so I don't know if it works. But you could compare
it to your driver.
To prove that your hardware is wired correctly, you could test it with
the Flex LCD driver in the CCS code library. Though, it only will test
the upper 4-bits of the LCD data bus. It's a 4-bit mode driver.
http://www.ccsinfo.com/forum/viewtopic.php?t=24661
I don't want to debug your 8-bit driver for you. |
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karthi27
Joined: 18 Nov 2009
Posts: 10
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| Reg... Flex Driver |
| Posted: Tue Dec 08, 2009 8:29 pm |
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This is what my project files include
Source files ----> lcdt.c (the test prog for flex_lcd.c driver)
Header files ----> 16f877.h
other files -----> lcdt.sta, ldct.sym, lcdt.tre
Should i include anything else?
_________________
Regards
Karthi |
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karthi27
Joined: 18 Nov 2009
Posts: 10
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| Not working |
| Posted: Tue Dec 08, 2009 8:59 pm |
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The Busy bit(DB7) and RS bits always high... the enable bit is always low(monitored them on LEDs). As usual only the first row is lit up.
This is driving me crazy. This is why I wrote my own LCD prog. Even that isn't working. Please help me in this concern to show some signs of life on my LCD.
This is how I modified... My project files include as stated above.
| Code: |
#=====Pin modified details in flex_lcd.c=======
#BYTE portb=6 //LOCATION OF REGISTER PORT B
#BYTE portc=7 //LOCATION OF REGISTER PORT C
#bit LCD_DB4=portb.4
#bit LCD_DB5=portb.5
#bit LCD_DB6=portb.6
#bit LCD_DB7=portb.7
#bit LCD_RS=portc.0
#bit LCD_E=portc.1
#bit LCD_RW=portc.2 |
_________________
Regards
Karthi |
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Tue Dec 08, 2009 9:14 pm |
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I have no idea what you're doing. You're not using the flex lcd driver.
It has several #define statements at the top where you are supposed
to list your PIC pins that are connected to the LCD. |
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