PIC16F690 EEPROM not retaining data

Hi,

I've got a very strange behaviour.

I write data to the internal eeprom with statement such as:

Code:

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    write healed_,healed       
    READ healed_,tempvar
    IF (tempvar != healed) then
        SOUND speaker,[100,200]
        LCDOUT $fe,1,"writeRoR"
        PAUSE 2000
    ENDIF

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and get no message, which means the write could be verified.
Then, when I turn off the circuit and turn on again, I display the values in the EEPROM and they are those I set at the time I flashed the PIC:

Code:

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DATA @10,0,0    'first hit
DATA @12,0,0
DATA @14,0,0
DATA @16,0,0
DATA @18,0,0
DATA @20,0,0

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It happens as if the EEPROM does not keep the data I WRITE.

Would anyone have an idea why??

Healed, Healed_ AND TempVar are Bytes?

Code:

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DATA @10,0,0    'first hit
DATA @12,0,0
DATA @14,0,0
DATA @16,0,0
DATA @18,0,0
DATA @20,0,0

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Is the above in the code you are running.

Quote:

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I display the values in the EEPROM and they are those I set at the time I flashed the PIC:

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If so, every time the PIC starts those values are written. If this is not the case then...

Nope.. DATA is performed at programming time only. :o

Quote:

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Originally Posted by mister_e

Healed, Healed_ AND TempVar are Bytes?

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healed is a BYTE var
healed_ is a CON pointing to the EEPROM location where I backup value of healed variabme
tempvar is a BYTE var

Quote:

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Originally Posted by mackrackit

Code:

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DATA @10,0,0    'first hit
DATA @12,0,0
DATA @14,0,0
DATA @16,0,0
DATA @18,0,0
DATA @20,0,0

---

Is the above in the code you are running.


If so, every time the PIC starts those values are written. If this is not the case then...

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Really?
I thought that DATA @... was only used at the time the PIC is programmed only.
Then How should I set initial values at programming time???

Quote:

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Originally Posted by mister_e

Nope.. DATA is performed at programming time only. :o

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Ah, that's what I thought, otherwise DATA would make no sense.
There is another instruction to alter EEPROM value: it is READ and WRITE

Hello xnihilo,
what does your code which makes healed_ into an address location look like ?

Thank you for your help but this time I could solve the problem:

I was using a routine that displays at the begining of the program the contents of the EEPROM at location 10 to 21 using an index var (hitnr).
Then later in the program I was writing to EEPROM using the index var BUT i forgot to reset the index var to its initial value after using it at the begining of my program so I was thinking I was writing to location 10 while the index var was already at 12. So when restarting the pic, I was displaying values of locations 10 and 11, that were still at 0 so I thought EEPROM write failed somehow. I was at the wrong memory offset...
Stupid error, I should get some sleep :)

Have a nice day.

Quote:

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Stupid error, I should get some sleep

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ME TOO. I was close.