I2CWRITE not writing anything on PIC18F45K80

[tumbleweed]

just saying... "Problem is definitely in arrays... but as soon their total length exceeds 24 bytes, issues start to appear. " doesn't seem to pan out.

The following reads three 16-byte arrays (48 bytes total) 20K times and verifies the arrayreads. No errors.
Same with the original two 16-byte arrays.

' device = 18F45K80

topline var byte [16]  'top part of the screen array
botline var byte [16] 'bottom part of screen
line3   var byte [16] 'more array data

ix var byte
ct var byte
cb var byte
c3 var byte

i var word
fail var word

fail = 0

for i = 0 to 20000
    ' clear arrays
    for ix = 0 to 15
        topline[ix] = 0
        botline[ix] = 0
        line3[ix]   = 0
    next ix

    ' read array data
    arraywrite topline,["ABCDEFGHIJKLMNOP"]
    arraywrite botline,["QRSTUVWXYZ[\]^_`"]
    arraywrite line3,  ["abcdefghijklmnop"]

    'read array char by char and check
    for ix = 0 to 15
        ct = topline[ix]
        if (ct-"A" <> ix) then fail = fail + 1
        cb = botline[ix]
        if (cb-"Q" <> ix) then fail = fail + 1
        c3 = line3[ix]
        if (c3-"a" <> ix) then fail = fail + 1
    next ix
next i

' check for failure
if (fail > 0) then
    i = fail
endif

Tried both PBP 3.16 and PBPL. No difference.

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

Post the complete code that doesn't work.

[CuriousOne]

Thanks, sure
this weekend

[CuriousOne]

The "complete" code is about 700 lines (and it is not complete yet).
Found another bug.
I call some subroutine, which uses own set of variables (verified)
after calling it, value of totally different variable (not used in that part of code) gets random values.

Very disturbing.
Can this be compiler issues or maybe faulty chip itself?

[richard]

Found another bug.
I call some subroutine, which uses own set of variables (verified)
after calling it, value of totally different variable (not used in that part of code) gets random values.


Very disturbing.
Can this be compiler issues or maybe faulty chip itself?

if you can produce a minimal, complete and verifiable example [MCVE] that demonstrates the problem it would be the first
ever case. do continue

[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.

[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.

[CuriousOne]

Yes I have read that.
But same manual also says that array size is limited for 16F series and only limited by available RAM on 18F, so I thought that this should work fine, but as it seems, it does not

Now I have another everlasting issue to solve - how to send $FE data via LCDOUT statement (it interprets $FE as command, not data transfer).
Solving this issue will help me to add ability to draw graphics to my ST7920 "Library".

[richard]

But same manual also says that array size is limited for 16F series and only limited by available RAM on 18F, so I thought that this should work fine

how can you interpret that to mean that writes involving array boundary violations are an acceptable programming technique ?

[CuriousOne]

Well, as my experience with ZX Spectrum BASIC shows (In case of array misreading: Error 3: Subscript wrong), when you do something not allowed, you will get an error message.
Even Visual Basic does that check.

[richard]

its totally up to you to decide how much time you are prepared to waste learning this lesson.

continually wheeling out the old "ZX Spectrum BASIC" excuse leads nowhere and never will , compiled code is what it is
you need to deal with it

[Ioannis]

Since the index to array can be number or calculation then it is not possible for the compiler to check that!

The interpreter is totally different story. Do not compare the two.

Richard has it just right.

Ioannis

[HenrikOlsson]

Exactly, we've been thru this before. Your beloved ZX Spectrum runs a BASIC interpreter which interprets and executes the code as it runs. It (the interpreter) can check things like out of bounds errors at run-time, a task that I'm sure makes array-indexing slow as f-k.

PBP is a compiler. It COMPILES your BASIC source into instructions that the PIC executes natively, it's not an interpreter. It is IMPOSSIBLE for the compiler to detect out of bounds issues at COMPILE TIME.

And even if the compiler was built to generate code that DID check array boundries on every access at runtime what do you suggest should happen when such an error is detected? It's not like there's a TV or monitor connected that can display the error message. Nope, the program would just crash with no way to tell the user why. In what way is that better than what it does now?

[CuriousOne]

Yes I know what is the difference between the compiler and interpreter.

And I'm not asking about RUNTIME error handling. I'm asking about boundary checking during the compile.
It can be clearly seen from the code that reading past array boundaries WILL occur in compiled code:

1. Compiler knows that X is starting from 0
2. Compiler knows that array is being read at X-16 position, which is definitely an error.

So some kind of notification like - "possible out of boundary array access" is very well possible and would be great.

[HenrikOlsson]

It can be clearly seen from the code that reading past array boundaries WILL occur in compiled code:

And yet, on 22nd April 2023, you said:

This is not issue of my code, because if I do not declare "topline" array, then "botline" reading works fine.

Clearly putting blame on anything BUT your code, be it the PIC itself, the compiler, the assembler or whatever - just not your code.

But, you're right, some situations could be confidently detected and some could be flagged as "potential" at compile time but it's a "can of worms".

As it is, the rules are clear and they are spelled out in the manual, section 7.6 that Ioannis pointed to earlier. You are responsibly, a fair price to pay for a powerful feature. It is what it is.

[CuriousOne]

Oh yes, XINST issues are solely my code fault too, right?

[HenrikOlsson]

Well, yes!

Since the compiler doesn't generate code for the extended instruction set the XINST config setting is set to OFF in the default configuration files for the devices that has that option.

Are you saying that is not the case for 45K80 and that there's a problem with the default config?

My humble guess is no, probably not. Instead you took a decision to change a default setting without knowing what it does. Things went south and once again it's the tools fault.

I'm not saying PBP and it's documentation is without shortcomings but, as has been proven, people don't read the documentation anyway. For example, can you honestly say that you went looking for XINST in the PBP manual BEFORE you decided to change that setting to ON or BEFORE tumbleweed pointed you the problem?

If you DID look for it in the manual you would've seen that every time it IS mentioned it shows the setting being OFF but you STILL decided to change it to ON and blame the tool.