arduino shield with magnetometer,clock,and OLED

Discussion in 'Embedded Systems and Microcontrollers' started by dreamtale, Nov 6, 2014.

  1. dreamtale

    Thread Starter New Member

    Oct 30, 2014
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    1
    hello everyone
    I want to make an arduino shield with display, also I want to integrate more functions. But now I have no more good ideas. Here are some simple function I want to achieve.
    First is the display, not the kind of big, ugly 1602 or 12864, it must be small, clear.
    So I chose 0.96 inch OLED, it's small, clear, I think it is the most suitable arduino display. If someone can give me a better choice, I would consider it.
    [​IMG]
    Second, the magnetometer is also included in the shield. I used HMC5883 as a magnetometer.I will display a compass on the OLED.
    Third, I put the DS1307 on the shield as RTC.
    Finally, I put HM06 Bluetooth on this board. SMD moudle.
    [​IMG]
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    As this is my first arduino shield design, I will make some and test it, very appreciative for any suggestions or ideas.
     
  2. sirch2

    Well-Known Member

    Jan 21, 2013
    1,008
    351
    Is the changing current drawn by the OLED as the display changes going to affect the magnetometer? I did some experiments with the magnetometer in my phone and I found that the magnetometer lost calibration if the screen brightness changed too much.
     
  3. dreamtale

    Thread Starter New Member

    Oct 30, 2014
    24
    1
    hi sirch2
    I can not adjust the brightness of the OLED, i can only control the lighting of each pixel.However, the number of illuminated pixels is may cause the current. .OLED's supply voltage is 5V, but the magnetometer's supply voltage is 5V, and I gave them isolation, but I do not know there is no effect.
    Thanks
    draemtale
     
  4. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    1,607
    I have not used most of your components excepting the RTC. I would have to consider the DS1307 basically obsolete as you can get a better clock with a built in temperature compensated crystal for the same price.

    Look into the PCF2129AT.
     
  5. dreamtale

    Thread Starter New Member

    Oct 30, 2014
    24
    1
    Thanks for your advice, I will look for more information on PCF2129. After that, I will decide whether to replace the RTC.
     
  6. sirch2

    Well-Known Member

    Jan 21, 2013
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    351
    I would suggest getting the magnetometer as far away as possible from the the display and any other components and conductors that draw significant current.
     
  7. dreamtale

    Thread Starter New Member

    Oct 30, 2014
    24
    1
    yeah,Thanks,I added some new features, I will re my PCB board layout and wiring in my free time.
     
  8. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    Did you prototype & test the schematic before you went to PCB?

    One really should, it greatly reduces the number of board spins.
     
  9. dreamtale

    Thread Starter New Member

    Oct 30, 2014
    24
    1
    Thanks,I tested each module individually.I made reference to some of the sparkfun design.
    In order to make sure my schematic is correct,I checked several times.
     
  10. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    But did you build the entire device from your schematic and test it?

    If the answer is "no" then you did not prototype the device. I hope you have the time and money in your budget for the extra board turn (or two).

    FYI: Even if you do prototype and test from the schematic the number of board turns to get an acceptable board is typically a number between 2 and 3.
     
  11. dreamtale

    Thread Starter New Member

    Oct 30, 2014
    24
    1
    Yes,Last night, I tested the entire schematic in breadboard.Arduino sometimes can not read the magnetometer data, I will try to solve this problem. I still worry about my PCB prototype will not succeed once.
     
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