Input Devices


When designign and manufacturing your board:

  • Don't add component of Ground, just add net and label it and name it to be GND and accept "Yes, connect."
  • Sometimes, the modela is old and won't machine the same depth to all parts of the board. In this case, change the depth of milling out traces (using the 1/64") to 0.25mil.
  • Make the most of your board: Change the set x,y, home from 20,20 to something closer to the edge corner.
  • Place hyour pin headers farther apart from each other so their heads don't interfere.
  • Sharing too many things on the same pin (in my case, the button and the PT, can work with or against you in your readings. Be purposeful.
  • When debugging your board and Arduino code:

  • Read the pin differences from ATTIny microcontroller to Arduino VERY carefully.
  • ALWAYS Burn Bootloader on Arduino for a new board. This tells it "hey, I'm arduino, it's good to meet you, now, you listen to me. Do this even if you already ran it to the FabISP you programmed.
  • See that PhotoTransistor Board in Neil's pages? It's telling you the Collector pad of the Phototransistor is in PARALLEL with the microcontroller pin (PB3) and the resistor, NOT in series!
  • Use CoolTerm as a debugger tool to Arduino, it'll tell you what is running and what is not.
  • Your range of readings should be between 0 and 1024 if your ADC (Analog Digital Converter) is placed at 10 bits or readings becuase 2 (the binary input for digital) ot the 10th power is 1024. To change this, you have to go deep into the Arduino program code.
  • For some reason DigiKey started making 10K Resistors that do not say that. Instead, they remain silent, with no writing. Don't let this intimidate you. It's all gonna be okay.
  • Schedule office hours with people or just walk into the CBA. People are friendly and invested in your learning. Take advantage of this! Again, thank you Charlessssss!
  • Chronological documentation of the process

    I decided to use this board towards my final project and decided the best way to count the dials on the rotary lever would be to wire a PhotoTransistor to an LED light that would be permanently on. I used the board from Embedded Programming week, removed the LED and corresponding resistor to an addendum board that would be powered through a 2x2-pin header, and added a phototransistor to the main board.

    Exported the monochrome PNG's (all very similar to the Electronics Design week here. (note png's below are not to scale...on purpose)

    Set up the modela with to do two boards. Note that if the board you have is too big for your sacrificial plate, you can use the paper cutter behind the modela to slice through the PCB board. Also, when making FDTI headers or 2x2 headers, you can always take a larger set (a row of header pins or a 2x3 header) and use a wire cutter (like the red one below) to cut through it and make it to the number of pins you need.

    Naturally, there were errors when first trying to program the board. Guru Diego and I tried but just weren't able to get it.

    I finally found Charles Fraccia in his office and he worked with me all morning to get it done! There were some obvious, unavoidable errors, and some not so much. See tips above for a solid run down of these.

    Finally! It works!

    Here's a video of the final thing working!
    Thank you so much to Prashant, Diego, and Charles for your kindness and patience!