I2CWRITE not writing anything on PIC18F45K80

[tumbleweed]

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

They're used BEFORE the "last call", they're used on EVERY call to gcoder, and they're NOT assigned values.
If that's how you think this all works you should give up now.

[CuriousOne]

OK, that was my fault, you're right
but I have caught this variable space array bug again. What happens here. If code I've selected with BOLD is active, it causes topline last byte to be replaced by space too.
So whenever there are even seconds, instead of last digit of the date at the end of the line, I'm getting an empty space.
As you can see, that code section does nothing - it just changes value of certain variable, which is not used elsewhere.
But if I comment that piece of code, the error is gone.

how this is possible?

#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
data $01, $03, $06, $0C, $18, $30, $60, $00 '/ side line { this char


'''''''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
separ var byte 'dual dot separator


'----------- 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


astart=0
aend=0                                     '1234567890ABCDEF
arraywrite topline, ["                "]
arraywrite botline, ["                "]
for c=0 to 24 step 8
gosub gcoder
next
drk:
gosub gettime


if CAMi.0=1 then  'blink the dots each second
separ=58
else
separ=32
endif



arraywrite TOPLINE, [dec saati dig 1,dec saati dig 0,32, dec cuti dig 1, dec cuti dig 0,32, dec cami dig 1, dec cami dig 0,32, dec TVE DIG 1, DEC TVE DIG 0,"{", DEC ricxvi DIG 1, DEC ricxvi dig 0]
C=0
'astart=1+16
'aend=2+16  
if cvlileba=1 then GOSUB GCODER
pause 50
goto drk




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 and astart<>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


gettime:
   I2CRead SDA, SCL, $D0, $00, [RTCSec, RTCMin, RTCHour, RTCDay, RTCDate, RTCMonth, RTCYear, RTCCtrl]
   CAMI=(RTCSEC >> 4)*10+RTCSEC // 16
   CUTI=(RTCmin >> 4)*10+RTCmin // 16 'decode seconds
   SAATI=(RTCHour >> 4)*10+RTCHour // 16 'decode hours
   TVE=(RTCmonth >> 4)*10+RTCmonth // 16 'decode month   
   RICXVI=(RTCdate >> 4)*10+RTCdate // 16 'decode month
   DGE=RTCday
     if DRO<>rtcsec then  'check for time changes, so display only is refreshed when time is changed
  cvlileba=1
  else
  cvlileba=0
  endif 
  DRO=rtcmin 
Return

[tumbleweed]

There are still places where things can go wrong, so until they're fixed all bets are off.

For example in gcoder you have the following (I've removed some of the code for clarity)

    FOR X=0 TO 30 step 2	'READ ARRAY INTO VARIABLE, ARRAY MEMBER CHAR=EEPROM OFFSET	
...
        FOR I=0 TO 7	'HELPER LOOP FOR CHARACTER READING
...
            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

Follow that code through for X=0 to 14. What happens to a and b?

[CuriousOne]

These are code parts which insert the empty space when in the array we do have code for ASCII space (32).
And this part of code works just fine.
The issue is that another, non-related part of code is causing problems.
Why changing value of certain variable, which is not used at all, causes issues with another variable?

[Ioannis]

Maybe because you are altering places in memory of the PIC that you are not aware of?

In the above example, if x=0, the

botline[x-16]=32 then a=0

how does evaluate?

Do you see the consequences of?

Ioannis

[tumbleweed]

And this part of code works just fine.
The issue is that another, non-related part of code is causing problems.
Why changing value of certain variable, which is not used at all, causes issues with another variable?

Ioannis gets it. You don't. That code doesn't "work just fine".

Your array index statements are screwed up, so you're accessing who knows what in memory.
That would explain the mysterious "I add unrelated code and things change".

There are any number of places for all that to go south... I don't trust many of those array accesses to be valid.

[CuriousOne]

Well, that is interesting.
As I understand, there is no "index out of bounds" error type supported by PBP?

I've modified that part of code to look like this:

if topline[x]=32 then a=0
if topline[x+1]=32 then b=0 'blanker


if X=>16 and botline[x-16]=32 then a=0
if x=>16 and botline[x-15]=32 then b=0

So far, works fine. Will keep you updated

[Ioannis]

Well, that is interesting.
As I understand, there is no "index out of bounds" error type supported by PBP?

Page 275 of the manual:

7.6.1 The Danger
The techniques about to be discussed are not monitored by PBP during compilation
or execution of the program. This means that you can write some crazy code that
could totally wreck the RAM on the PIC MCU. PBP won't warn you or generate an
error message.

The greatest opportunity for trouble lies in the fact that PBP doesn't monitor (isn't
even aware) of array variable sizes. When you declare an array in PBP and specify
a size, all that really happens is that PBP skips a number of RAM locations after the
base variable name is allocated.

my_array VAR WORD[16]   ' Allocates "my_array" as two
                           bytes, then skips (reserves) a
                           block of 30 bytes in RAM

Even if you blatantly write to a location that is beyond the size of an array you created,
PBP won't complain.