I2CWRITE not writing anything on PIC18F45K80

[tumbleweed]

The "complete" code is about 700 lines (and it is not complete yet)

You just said...

I just wrote another code, which simply reads values of array and writes data on 1602LCD.
Issue still exists

That's the code that's 700 lines?

If you're having issues then continuing to add more code isn't going to help.
You should stop, and start trimming things down bit by bit until it starts working.
Then you'll know what to look at.

While compiler and chip issues are always a possibility, there's a much better chance you're just doing something wrong.

[CuriousOne]

No that different code
Now I'm back to "big" code.

I'm trying now to isolate the problem and writing all from the scratch, part by part, verifying.

[CuriousOne]

What I 100% figured out, by writing the small code is the 18F issue with ST7920 LCD.
When I turn on the graphic mode, by sending LCDOUT $FE,$2E , there are high chances that random character in text mode will be displayed in top left corner.
I tried adjusting timings and OSC settings - no change. Same code, same PCB, same LCD - no issues with 16F1939.

[CuriousOne]

OK here it is. Here's a code.
It works properly only on first run after the flashing the code. If I unplug the power, next it will run with the same error.
The left picture shows correct result, how display should look, and right picture shows how it looks after cycling the power.

#config
CONFIG RETEN = OFF	
CONFIG INTOSCSEL = HIGH
CONFIG SOSCSEL = DIG
CONFIG XINST = OFF	    ;Enabled
CONFIG FOSC = INTIO1
CONFIG PLLCFG = OFF
CONFIG FCMEN = OFF	    ;Disabled
CONFIG PWRTEN = OFF	    ;Disabled
CONFIG BOREN = OFF	    ;Disabled in hardware, SBOREN disabled
CONFIG WDTEN = OFF	    ;WDT disabled in hardware; SWDTEN bit disabled
CONFIG CANMX = PORTB
CONFIG MCLRE = OFF


#endconfig


OSCTUNE.6 = 1 ; Enable 4x PLL
OSCCON = %01110000
ANCON1=0 'DISABLE ADC D3-D2-D1-D0-
ANCON0=0
ADCON0=0
TRISC=%11110000 'set PORTC as output first 4
TRISD=%00000000 'set PORTD as output all
TRISB=%00000000 'set PORTB as output all
TRISA=%00000000 'set PORTA 2 as input, others as output
TRISE=%0000000  'set PORTE as output all
define OSC 64


DEFINE LCD_DREG PORTD 
DEFINE LCD_DBIT 4  
DEFINE LCD_RSREG PORTB  
DEFINE LCD_RSBIT 5  
DEFINE LCD_EREG PORTA  
DEFINE LCD_EBIT 3  
DEFINE LCD_BITS 4  
DEFINE LCD_LINES 2  
DEFINE LCD_COMMANDUS 850  
DEFINE LCD_DATAUS 30


'i var byte
high portb.4 'enable LCD backlight


'digits
data $3E, $67, $6F, $7B, $73, $63, $3E, $00 'NOLI
data $1C, $3C, $6C, $0C, $0C, $0C, $7F, $00 'ERTI
data $3E, $63, $03, $3E, $60, $60, $7F, $00 'ORI
data $3E, $63, $03, $0E, $63, $63, $3E, $00 'SAMI
data $63, $63, $63, $3F, $03, $03, $03, $00 'OTXI
data $7F, $60, $60, $7E, $03, $63, $3E, $00 'XUTI
data $3E, $63, $60, $7E, $63, $63, $3E, $00 'EQVSI
data $7F, $63, $03, $06, $0C, $0C, $0C, $00 'SHVIDI
data $3E, $63, $63, $3E, $63, $63, $3E, $00 'RVA
data $3E, $63, $63, $3F, $03, $63, $3E, $00 'CXRA
'SYMBOLS
data $00, $00, $18, $18, $00, $18, $18, $00 'orcertili
data $00, $00, $18, $18, $00, $18, $18, $30 'certilmdzime
data $06, $0c, $18, $30, $18, $0c, $06, $00 'aket
data $00, $00, $7e, $7e, $00, $7e, $7e, $00 'tolia
data $30, $18, $0C, $06, $0C, $18, $30, $00 'iket
data $3E, $63, $63, $06, $0C, $00, $0C, $00 'KITXVA
data $7C, $C6, $DE, $F6, $DC, $C0, $7E, $00 'LOKOKINA


'font georgian alphabet without squeek door
data $0C, $0C, $06, $03, $63, $63, $3E, $00' data ' Char 048 (0)
data $38, $0C, $0C, $3E, $63, $63, $3E, $00'data ' Char 049 (1)
data $26, $63, $66, $63, $63, $63, $3E, $00'data ' Char 050 (2)
data $3E, $63, $63, $7E, $60, $60, $3E, $00'data ' Char 051 (3)
data $3E, $63, $03, $03, $63, $63, $3E, $00'data ' Char 052 (4)
data $36, $6B, $6B, $36, $03, $63, $3E, $00'data ' Char 053 (5)
data $3E, $63, $03, $1E, $33, $63, $3E, $00'data ' Char 054 (6)
data $1E, $03, $0E, $03, $0E, $63, $3E, $00'data ' Char 055 (7)
data $3E, $63, $63, $63, $63, $63, $22, $00'data ' Char 056 (8)
data $0C, $3F, $0C, $06, $63, $63, $3E, $00'data ' Char 057 (9)
data $06, $03, $0E, $03, $63, $63, $3E, $00'data ' Char 058 (:)
data $3E, $63, $63, $62, $60, $60, $3E, $00'data ' Char 059 (;)
data $3E, $63, $03, $3F, $63, $63, $3E, $00'data ' Char 060 (<)
data $7F, $60, $60, $7E, $63, $63, $3E, $00'data ' Char 061 (=)
data $3E, $6B, $6B, $6B, $63, $63, $22, $00'data ' Char 062 (>)
data $0C, $06, $03, $06, $63, $63, $3E, $00'data ' Char 063 (?)
data $03, $03, $0F, $1B, $03, $63, $3E, $00'data ' Char 064 (@)
data $60, $60, $60, $7E, $63, $63, $63, $00'data ' Char 065 (A)
data $60, $60, $60, $63, $63, $63, $3E, $00'data ' Char 066 (B)
data $2E, $6B, $6B, $63, $63, $63, $3E, $00'data ' Char 067 (C)
data $36, $6B, $4B, $03, $63, $63, $3E, $00'data ' Char 068 (D)
data $3E, $63, $03, $06, $63, $63, $3E, $00'data ' Char 069 (E)
data $3E, $6B, $60, $7E, $63, $63, $3E, $00'data ' Char 070 (F)
data $60, $60, $60, $7E, $63, $63, $3E, $00'data ' Char 071 (G)
data $63, $63, $63, $3F, $03, $63, $3E, $00'data ' Char 072 (H)
data $38, $6C, $6C, $3E, $1B, $1B, $0E, $00'data ' Char 073 (I)
data $3E, $6B, $6B, $6B, $6B, $6B, $32, $0 'data for TH [
data $07, $4F, $5B, $33, $03, $63, $3E, $00 '\ jh
data $3E, $6B, $6B, $62, $60, $60, $3E, $00 '] RR
data $36, $5B, $03, $3F, $63, $63, $3E, $00 '^sh
data $3C, $66, $6C, $7E, $63, $63, $63, $00  '_ ch
data $03, $03, $03, $3F, $63, $63, $3E, $00  '` dz


'indicators  CORRESPOND SMALL LETTERS
data $EC, $A4, $A4, $A4, $A4, $A4, $EE, $00 '01
data $EE, $AA, $A2, $AE, $A8, $A8, $EE, $00 '02
data $EE, $A2, $A2, $AE, $A2, $A2, $EE, $00 '03
data $EA, $AA, $AA, $AE, $A2, $A2, $E2, $00 '04
data $EE, $A8, $A8, $AE, $A2, $AA, $EE, $00 '05
data $EE, $AA, $A8, $AE, $AA, $AA, $EE, $00 '06
data $EE, $AA, $A2, $A2, $A2, $A2, $E2, $00 '07
data $EE, $AA, $AA, $AE, $AA, $AA, $EE, $00 '08
data $EE, $AA, $AA, $AE, $A2, $AA, $EE, $00 '09
data $CE, $4A, $4A, $4A, $4A, $4A, $EE, $00 '10
data $CC, $44, $44, $44, $44, $44, $EE, $00 '11
data $CE, $42, $42, $4E, $48, $48, $EE, $00 '12
data $CE, $42, $42, $4E, $42, $42, $EE, $00 '13
data $CA, $4A, $4A, $4E, $42, $42, $E2, $00 '14
data $CE, $48, $48, $4E, $42, $4A, $EE, $00 '15
data $CE, $48, $48, $4E, $4A, $4A, $EE, $00 '16
data $CE, $4A, $42, $42, $42, $42, $E2, $00 '17
data $CE, $4A, $4A, $4E, $4A, $4A, $EE, $00 '18
data $CE, $4A, $4A, $4E, $42, $4A, $EE, $00 '19
data $EE, $AA, $2A, $EA, $8A, $8A, $EE, $00 '20
data $EC, $A4, $24, $E4, $84, $84, $EE, $00 '21
data $EE, $AA, $22, $EE, $88, $88, $EE, $00 '22
data $EE, $A2, $22, $EE, $82, $82, $EE, $00 '23
data $EA, $AA, $2A, $EE, $82, $82, $E2, $00 '24
data $10, $28, $48, $48, $48, $28, $10, $00 'light oFF
data $20, $56, $90, $96, $90, $56, $20, $00 'LIGHT ON


'''''''LCD HANDLER VARIABLES
x var byte ' counter variable
z var WORD ' temp variable
y var WORD 'eeprom reader var
i var byte 'counter
a var byte
b var byte  'temps
c var byte
astart var byte 'inversion atribute start
aend var byte 'inversion end


'----------- RTC 


RTCYear  Var Byte: RTCMonth Var Byte: RTCDate  Var Byte: RTCDay   Var Byte: RTCHour  Var Byte
RTCMin   Var Byte: RTCSec   Var Byte: RTCCtrl  Var Byte 
SDA VAR PORTB.3
SCL VAR PORTB.2


SAATI VAR BYTE
CUTI VAR BYTE
'CELI VAR BYTE
TVE VAR BYTE
RICXVI VAR BYTE
DGE VAR BYTE 
CAMI VAR BYTE
dro var byte
cvlileba var byte 'clock trigger set




'------------- PCF IO
padr var byte
PSDA var portd.0
PSCL var portd.1




'-----GLOBAL VARIABLES
ABSTIME VAR WORD 'CURRENT ABSOLUTE TIME, HOURS*60+MINUTES FROM RTC
MENUITEM VAR BYTE 'CURRENT MENU POSITION VARIABLE
time var bit[24] 


'INPUTS
UPBT VAR PORTC.5 'UP BUTTON
DNBT VAR PORTC.4 'DOWN BUTTON
LBUT VAR PORTC.7 'LEFT/BACK BUTTON
RBUT VAR PORTC.6 'RIGHT/OK BUTTON 


sdao var portd.0
sclo var portc.3


'OUTPUTS PCF  - 66 CON EDGE, 64 MIDDLE, 78 BUTTON SIDE
adr var byte  'OUTPUT PCF ADDRESS
adr=78


 '[\]`^_  th zh R dz sh ch
topline	var byte [32]  'top part of the screen array
botline var byte [32] 'bottom part of screen


lcdout $fe, $20 'enable text mode -  this is required to fix issue of 18F
LCDOUT $FE,$2, "TEST"
pause 100
LCDOUT $FE,$2, "    "
pause 500
LCDOUT $FE,$2E  'enable graphic mode
pause 500
'z=0
gosub gpt 'clear screen
                                     '1234567890ABCDEF
arraywrite topline, ["1234567890ABCDEF"]
arraywrite botline, ["GHIJKLMNOPQRSTUV"]
for c=0 to 24 step 8
gosub gcoder
next
astart=5
aend=10
arraywrite BOTLINE, ["SACDELI XAZI z  "]
C=24
GOSUB GCODER




stop












GCODER:
FOR X=0 TO 30 step 2	'READ ARRAY INTO VARIABLE, ARRAY MEMBER CHAR=EEPROM OFFSET	
if X<15 then
Y=(topline[x]-48)*8
Z=(topline[x+1]-48)*8 'READ  INTO VARIABLE AS TWINS
endif


if x>15 then
Y=(botline[x-16]-48)*8
Z=(botline[x-15]-48)*8 'READ  INTO VARIABLE AS TWINS
endif




FOR I=0 TO 7	'HELPER LOOP FOR CHARACTER READING
LCDOUT $FE,$80+c+i 'UPDATE Y POSITION
LCDOUT $FE,$80+x/2 'UPDATE X POSITION
READ Y+I,A 'READ EEPROM BYTES INTO VAR
READ Z+I,B


if topline[x]=32 or botline[x-16]=32 then a=0
if topline[x+1]=32 or botline[x-15]=32 then b=0 'blanker


if X=>astart and x<=aend then
a=A^%11111111
b=b^%11111111
endif


if a=$FE then a=0
if b=$fe then b=0
LCDOUT a
LCDOUT b 'WRITE TO SCREEN
NEXT I
NEXT X
return


GPT:
for y=0 to 30 step 2
LCDOUT $FE,$80+y
LCDOUT $FE,$80
FOR x=1 TO 16
LCDOUT 0
NEXT
next
return

[CuriousOne]

The position of inversion depends on two variables, ASTART and AEND.
They are assigned values of 5 and 10.
On 1st run code works fine and inversion starts at 5th char and ends on 10th.
But after power off and back on, seems like these two variables are not same any more.

[tumbleweed]

The variables astart and aend are not assigned values until right before the last time gcoder is called.
What do you expect them to be the first time the program runs since they are uninitialized?

[CuriousOne]

"The last call" of gcoder is the code that makes that inversion, so variables are assigned before their use.