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Pota78
Joined: 09 Sep 2005 Posts: 16
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Strange EEprom Errors.. |
Posted: Fri Oct 07, 2005 2:39 am |
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Hi all, i'm experimenting some unusual and very strange errors with an EEprom...
I'm using a 16f877A and a 25lc640 eeprom and I have written some routines to write to and to read from the eeprom without using the spi_write and the spri_read routines.
I tested the addresse between 1 and 10 and it seemed to work all right (writing and reading) but when I try to write in the range between 1 and 50 (repeat 0xAA from address 1 to address 50) this is what I found in the EEprom:
AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA AA
AA 80 AA 80 AA FF AA 80
AA 80 AA 80 AA FF AA 80
E6 E6 E6 E6 E6 E6 E6 E6
E6 E6 E6 E6 E6 E6 E6 E6
AA AA
and the scheme repeats itself until address 80 and then I found only E6s...
Maybe it is an error in the write and read functions, anyway, does anyone of you know if there are differences in the structure of a 25lc640 that can justify these strange effects?
Thank you all, Pota |
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Humberto
Joined: 08 Sep 2003 Posts: 1215 Location: Buenos Aires, La Reina del Plata
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Posted: Fri Oct 07, 2005 8:31 am |
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I have written some routines to write to and to read from the eeprom without using the spi_write and the spri_read routines.
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The only way to access the 25LC640 Serial EEPROM is using SPI protocol. If you had
written your own routines to access it, how do you imagine we can help you?
Post a short code example that demostrate the found error.
Best wishes,
Humberto |
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Mark
Joined: 07 Sep 2003 Posts: 2838 Location: Atlanta, GA
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Posted: Fri Oct 07, 2005 8:49 am |
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Humberto wrote: | Quote: |
I have written some routines to write to and to read from the eeprom without using the spi_write and the spri_read routines.
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The only way to access the 25LC640 Serial EEPROM is using SPI protocol. If you had
written your own routines to access it, how do you imagine we can help you?
Post a short code example that demostrate the found error.
Best wishes,
Humberto |
What, you can't read minds? |
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Humberto
Joined: 08 Sep 2003 Posts: 1215 Location: Buenos Aires, La Reina del Plata
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Posted: Fri Oct 07, 2005 9:08 am |
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What, you can't read minds?
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Unfortunately NO.
Instead I would be drinking a Martini in Malibu and not reading this forum.
regards,
Humberto
Last edited by Humberto on Sat Oct 08, 2005 7:16 am; edited 1 time in total |
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rnielsen
Joined: 23 Sep 2003 Posts: 852 Location: Utah
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Posted: Fri Oct 07, 2005 1:50 pm |
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Makes perfect sense to me. I think I'll hold off on helping and let him learn more by struggling to find the answer himself.
Ronald
What does a Mathematician do when he gets constipated?
He works it out with a pencil. |
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treitmey
Joined: 23 Jan 2004 Posts: 1094 Location: Appleton,WI USA
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Posted: Fri Oct 07, 2005 2:39 pm |
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Suppose thats better that a slide-rule |
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Humberto
Joined: 08 Sep 2003 Posts: 1215 Location: Buenos Aires, La Reina del Plata
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Posted: Fri Oct 07, 2005 7:18 pm |
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He works it out with a pencil.
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Suppose thats better that a slide-rule..
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Why do yours suppose he doesn´t use a cientific calculator ?
Humberto |
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