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oconnor.jb

Member Since: February 7, 2014

Country: United States

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Computer Science teacher at South Forsyth High School, Cumming, GA Used to build synthesizers and computer peripherals in HS and college; wish I had Arduinos to play with back then! Now, I try to find enough time to build “proof of concept” projects for my students, to learn new things to teach them, and inspire their creativity.

  • I’m just looking for a reliable way for students to connect Arduino devices/projects to a network, and I’m happy doing it with a wired connection if it works. I’ve tried 2 different WiFi shields now and neither one seems to work reliably and EASILY out of the box. Being able to connect an Arduino project to the network seems to be the most promising way to get students more excited about building more complex devices.

  • I have been using the abbreviations RTFI and RTFM for years with my students (Student: “Why isn’t my program working?”, Me: “You have an RTFM error.”), so when I unpacked my SIK and took out the RedBoard and saw the “RTFM” logo on the packaging underneath I laughed for hours. Thanks SF for a nice kit (it has become my personal “proof of concept” kit) and the humorous packaging.

  • Thanks. I’m using the shift register available from SparkFun (TI chip), and while I couldn’t decipher for sure from the datasheet, the fact that you said “some would” was enough for me to give it a try. It worked great. I wrote the code to do it both ways - cycling through digits, turning on all segments, then writing the registers AND cycling through the segments one at a time. Got about the same brightness on the segments either way. I started out using a 330ohm resistor for each digit cathode, but found that if I just connect directly to the shift register pin I get a bright display without frying the segment (blue LEDs).

    My test code just counts from 1 to 9999, but I added in a delay between each segment that descends from 250 to 0 and then resets as each number in the count changes, so I get a nifty visual effect as the count approaches multiples of 250.

  • I was able to get one of these working with a shift register to control the segments, but still used pins on my RedBoard to select digits. Can a shift register also sink current, link an Arduino GPIO pin, so that I could do the digit selection through the shift register too?

  • will the register pins on one of these sink current? I have successfully used one to control the segments on common cathode 4-digit display but I’m still using 4 pins on my Arduino to make the digit selection with. I would like to chain two of these shift registers together and use 4 bits from the 2nd register to control the digits. Ultimately, I’d like to try using 3 of them to control 2 4-digit displays for a total of 8 digits (and, yes, I know I could get one chip to do all that, but I’m trying to design projects for my students that will make them have to do some trickier programming, and coming up with “non-standard” hardware solutions is the only way to keep them from just copying code of the Internet).

No public wish lists :(