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joy.philipz
Joined: 23 Nov 2013 Posts: 2
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MCP79522 RTC not working |
Posted: Mon Nov 25, 2013 2:11 am |
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I am trying to use MCP79522 with dspic33fj128GP710A controller without success. Able to read and write RTC and ram registers, but RTC not working. Reading the values same as written.
Always writing ST bit (0x80) high along with seconds, but nothing happens to seconds, it stays in the same value.
I am able to enable VBAT, and it maintain the ram values after power reset.
Any help/ suggestion?
Joy |
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Ttelmah
Joined: 11 Mar 2010 Posts: 19366
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Posted: Mon Nov 25, 2013 4:15 am |
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That's how it'll behave, if there is a tiny whisker short round the oscillator/crystal pins somewhere, or the crystal is not actually making contact. Oscillator can't start, so none of the time registers change. Have seen this.
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joy.philipz
Joined: 23 Nov 2013 Posts: 2
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MCP79522 RTC not working |
Posted: Mon Nov 25, 2013 10:16 pm |
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Ttelmah wrote: | That's how it'll behave, if there is a tiny whisker short round the oscillator/crystal pins somewhere, or the crystal is not actually making contact. Oscillator can't start, so none of the time registers change. Have seen this.
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Thanks for the reply. I have checked crystal, removed and connected again, and not found anything. Will assemble second board and try.
Cheers
Joy |
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