LCD and PIC16F2620 problem

pekka1234 · Joined: 28 May 2017 Posts: 83

Hey. I have tried to solve this problem about two weeks.
I do level meter, but then I needed to use PIC18F2620.
It seems to be simple to replace PIC16F886.

My meter is here http://probyte.fi/LEVELMeter.jpg
and schematic is here http://probyte.fi/OK.jpg

I can't get simple LCD init to work.

I have tried with old (but PIC16) codes, changed to PIC18F code.
The LCD do not convert to 2 row and doesn't show any code.

How ever I have got LCDInit to work once, but I have not source code any more.
Have anybody a PIC18F and LCD code?
Or can you help me.

Pekka
Here is my code:

pekka1234 · Joined: 28 May 2017 Posts: 83

I have 5.115 version of CCS

Pekka

Ttelmah · Joined: 11 Mar 2010 Posts: 19539

Your code will probably not work, because you have an INT_RDA, that does
not call a getc inside. If this triggers your processor will be hung.
INT_RDA, cannot clear the interrupt, unless the character is read. So
if this gets called, it'll be called 'forever' and all other operations will
stop......

On the LCD code, there is standard code with the compiler, or use
PCM_Programmer's LCD code in the code library. This works and in
simple reliable code.

pekka1234 · Joined: 28 May 2017 Posts: 83

I deleted INT_RDA off, but it has no meaning
The serial code is following:

LCD init end
Program start
Program start
Program start
Program start
==
The CCS LCD example is quite different and much more complicated.
I have tried to use it but can't get it work.
But I try it again.

temtronic · Posted: Sun May 05, 2024 2:08 pm

#1 delete ALL WDT code !!! You do NOT need the WDT at this stage and it can cause all sorts of weird problems.

#2 I have used PCM P's LCD driver on PIC18F46K22 products for years. It WORKS.

#3 delete ALL timers and other code, not necessary and can cause 'problems'

Concentrate on getting the LCD to display properly. I call that the 'Hello World' program.

When that works, copy, rename and edit the new program for more code. That way you can go back to the WORKING 'Hello Program' and try again.

pekka1234 · Joined: 28 May 2017 Posts: 83

Temtronic
Thank for help.
I removed all WDT functions and cleared other not used parameters
I tried to load it to my PCB, but it doesn't work.

[/code]

/*=============================================
Project: Angelmeter with Murata sensor SCL3300-10
LCD RC-2002A-BIW-ES 2*20 characters
5V VCC
code:lcd.c and pic18reg.c
===================================================*/
#include <18F2620.h>
#device ADC=10
#FUSES NOWDT //No Watch Dog Timer
#FUSES INTRC_IO //Internal RC Osc, no CLKOUT
#FUSES NOPROTECT //Code not protected from reading
#FUSES IESO //Internal External Switch Over mode enabled
#FUSES BROWNOUT //Reset when brownout detected
#FUSES PUT //Power Up Timer
#FUSES NOCPD //No EE protection
#FUSES NODEBUG //No Debug mode for ICD
#FUSES NOLVP //No low voltage prgming, B3(PIC16) or B5(PIC18) used for I/O
#FUSES NOWRT //Program memory not write protected
#FUSES FCMEN //Fail-safe clock monitor enabled
#FUSES NOMCLR //Master Clear pin not enabled
#FUSES NOWRT
#include "pic18reg.h"

#use delay(clock=8000000)
#use rs232(baud=9600, parity=N, xmit=PIN_C6, rcv=PIN_C7,errors, bits=8) // RS232 asetukset

#define LCD_ROW1 0x80
#define LCD_ROW2 0xA8
#define LCD_ROW3 0xC0

#bit PWM_BIT = PORTC.2
#byte SSPCON1 =0xfc6
#bit SSPEN =SSPCON1.5

#define CMD 0
#define DATA 1
#BIT DB3 = PORTB.3
#BIT DB2 = PORTB.2
#BIT DB1 = PORTB.1
#BIT DB0 = PORTB.0
#BIT RS = PORTB.4
#BIT ENABLE = PORTC.5

#include <string.h>
#include <ctype.h>
#BIT Underled = PORTC.0
#BIT SOUND = PORTC.2
#BIT Overled = PORTC.3
#define BUTTON PIN_B5 //button
#INCLUDE <stdlib.h>
char LCDBuffer[26];
unsigned int8 delay; //
#define MAXCOUNT 5
char c; //

void printlcd1();
void printLcd2();
void clear_lcd();

#define lcd_type 2 // 0=5x7, 1=5x10, 2=2 lines
#define lcd_line_two 0x40 // LCD RAM ADdEss m

int8 const LCD_INIT_STRING[4] =
{
0x20 | (lcd_type << 2), // Mode 4-bit, 2 rows = 0x28
0xc, // dislay on
1, // clear display
6 // move cusor pn step forwardsiirrä
};

/*=============================

==========================*/
void lcd_send_nibble(int8 nibble)
{
if ( nibble &1)
DB0 =1;
else
DB0 =0;
if ( nibble &2)
DB1 =1;
else
DB1 =0;
if ( nibble &4)
DB2 =1;
else
DB2 =0;
if ( nibble &8)
DB3 =1;
else
DB3 =0;
delay_us(1);
set_tris_c(0);
ENABLE =1;
output_high( PIN_C5);
delay_us(20);

ENABLE =0;
output_low( PIN_C5);
delay_us(10);

}

/*==============================================

========================================*/
void lcd_send_byte(unsigned int8 ASCII_CHAR, unsigned int8 n)
{

RS=1;
ENABLE=1;

if(ASCII_CHAR) // ASCII Data?
RS=1; // RS mode =1
else
RS=0; // RS_MODE =00 or LCD command
delay_us(20);
ENABLE =0;
lcd_send_nibble(n >> 4); // first Hi nibble
lcd_send_nibble(n & 0xf); // then LOW nibble
delay_ms(1); // 60 us is enough
}

/**********************************
init LCD
*********************************/
void lcd_init(void)
{
unsigned int8 i;

RS=0;
ENABLE =0;
delay_ms(20);
for(i=0 ;i < 3; i++)
{
lcd_send_nibble(0x03);
delay_ms(10);
}
lcd_send_nibble(0x02);
for(i=0; i < sizeof(LCD_INIT_STRING); i++)
{
lcd_send_byte(CMD, LCD_INIT_STRING[i]);
delay_ms(10);
}
}
void row1( void) { // go row 1
lcd_send_byte(CMD, LCD_ROW1);
}

void row2( void) {// go to row2
lcd_send_byte(CMD, LCD_ROW2);
}
void clear_lcd(void) {
lcd_send_byte(CMD,1); // clear LCD
}

/*================
Display
==============*/
void printlcd1( void) {
unsigned int8 i=0;
char c;
row1();

for ( i=0; i<strlen(LCDBuffer); i++) {
c=LCDBuffer[i];
lcd_send_byte(DATA,c);
}
}

void printLcd2( void) {
unsigned int8 i,c;
row2();
for ( i=0; i<strlen(LCDBuffer); i++) {
c=LCDBuffer[i];
lcd_send_byte(DATA,c);
}

}
void lcddelayTxtRow2 ( void) {

sprintf(LCDbuffer, "Delay %ds " , delay);
printLcd2();// disply the rwault 2. row
}

// init Hardware
void initHardware ( void)
{
setup_oscillator(OSC_8MHZ);
setup_comparator( NC_NC_NC_NC);
setup_spi(FALSE); // THis must be before TRIS command !!
port_b_pullups(TRUE); // INTCON2.7 =0
set_tris_b(0b11000000);
set_tris_c(0b00001111);

SSPEN =0;

}

/*********************************

**********************************/
void main(void)
{

delay_ms(100);
initHardware ();

lcd_init(); // THE VEEY IMPORTANT FUCTION
printf("\rLCD init end");

while(1)
{
sprintf( LCDBuffer,"Hello World");
printlcd1();
delay_ms(500);
printf("\rProgram start ");

}

} [/code]
I have tried to load CCS LCD program, but it is very complicated.
Can you help me how to modify this program to 18F2620 and 4 bit data in port B.
RB4 - PIN_B0, RB5-PIN_B1, RB6 -PIN_B2, RB7-PIN B3, RS -PIN_B4 and Enable PIN_C5. WR pin is not used.

Pekka

Ttelmah · Joined: 11 Mar 2010 Posts: 19539

As you have been told twice, use PCM_Programmers LCD driver (from the
code library here). This is much more flexible than the standard driver,
and is one of the really reliable bits of code, that makes life easier for
everyone.

dyeatman · Joined: 06 Sep 2003 Posts: 1934 Location: Norman, OK

I have used PCM programmers LCD driver on numerous 16/18/24 and DsPICs
with no issues. Much easier than the CCS LCD driver and highly recommended.
_________________
Google and Forum Search are some of your best tools!!!!

pekka1234 · Joined: 28 May 2017 Posts: 83

OK
I found flex_lcd.c in here.
I modified it and tried with my LCD driver.

It worked !
The display was not clear, but there was some charters.
And two rows!

Then I tried it second and more times, but not more working?

Pekka

pekka1234 · Joined: 28 May 2017 Posts: 83

LCD problem solved!

I got today LCD working.
It was Enable bit was open.

I had not operating PIN_C4 and I changed it to PIN_C5,
but it was under trimmer potentio meter and it was difficult to put in operation.

Anyway I am very thankful all who tried to help me.

I will return to my original program.
Here is my working LCD
http://probyte.fi/LCDDISPLAY.jpg

Pekka Finland