I2CWrite issue


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Thread: I2CWrite issue

  1. #1
    robertmark68's Avatar
    robertmark68 Guest

    Angry I2CWrite issue

    Please forgive me if this query is in the wrong section....

    I have a 16F877A setup to talk via I2C to THREE AD5282 Digital Potentiometers.

    These devices have 2 Address lines AD0,AD1 that i have set to unique values.

    My SDA & SCL lines are pulled-up through 4.7K resistors.

    Here is my issue.

    I have my code setup to write a value to one of my digipots...which it does successfully!

    However when I try to write to another the value CHANGES on the digipot i just wrote too!!!

    This what i have observed....

    When I power up the PCB the SDA and SCL lines are pulled high...naturally.

    When I write to one of my digipots via I2C the SDA and the SCL lines transition as you would expect....

    But after the write....the SCL remains LOW!!!!

    This can't be good...shouldn't go back HIGH after a successful write?

    I have gone through the forum and I have made sure I havent done anything stupid....

    ie...I am not using constants in my I2CWRITE lines...but even if i were it shouldn't matter as the devices only use BYTES

    Can anyone shine a little light on me?

    Robert in Massachusetts

  2. #2
    robertmark68's Avatar
    robertmark68 Guest


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    Talking Oh My God!!!!

    12 hours!!!!

    12 @#$%^& HOURS!!!!!

    I wasted 12 hours on this problem and all I needed was BRACKETS around my data?!?!!?!?!?


    I really REALLY REALLY need a DRINK!!!!!

    Robert

  3. #3
    Join Date
    Jul 2005
    Posts
    78


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    Default

    At first I was thrilled to read your post, as I'd asked the same several months back and got no (usefull) replies, just the standard RTFM stuff. Wow, I can help this guy I think.

    Then I saw your reply to yourself.

    JUST 12 hours? I spent about 3 days looking for those brackets.



    My only question is why this doesn't generate a compiler error?

    Why just make bad code?

  4. #4
    Payatronico's Avatar
    Payatronico Guest


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    Red face este... en español o ingles?

    I have the same problem with the "·$%&/) RTC, why don't use BRACKETS in the examples?

    You take 3 days, the other one take 3 days, I spend one week... so I am the best stupid? I win I win I win yeaaaa
    Last edited by Payatronico; - 20th September 2006 at 01:41.

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