I2CWRITE not writing anything on PIC18F45K80

[CuriousOne]

LOL.
I'm trying to explain that if I add one extra array definition, another array gets screwed. How this is related to LCD?
I just wrote another code, which simply reads values of array and writes data on 1602LCD.
Issue still exists - data in array gets damaged, if total array length exceeds 24 bytes.

[tumbleweed]

I just did this with an 18F45K80

' device = 18F45K80

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

ix var byte
ct var byte
cb var byte

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

' read array data
arraywrite topline,["0123456789ABCDEF"]
arraywrite botline,["0123456789ABCDEF"]

ix = 0

'read array char by char
for ix = 0 to 15
    ct = topline[ix]
    cb = botline[ix]
next ix

ix = 0

When it gets to the end, topline and botline arrays are exactly as specified... each is 16 chars "0"-"F"
Reading the arrays byte by byte also does as expected.
I even added a third array of 16 chars... works too.

Your problem is elsewhere... not with the arrays themselves.

[CuriousOne]

Thanks, have you tried to read the same array several times?
Problem is definitely in arrays, because if I make say topline 4 bytes and botline 16 bytes (even without writing anything to any of them) - there are no problems, but as soon their total "length" exceeds 24 bytes, issues start to appear.

[richard]

Your problem is elsewhere... not with the arrays themselves.

code snippets , a complete waste of time and effort

[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