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StuffAndyMakes

Member Since: August 17, 2009

Country: United States

  • I've been using Chrome on all my Macs for almost as long as it's been available. It's fast, developer-friendly and recovers from a crash nicely (restore all tabs/windows). Safari is nice and is similar to Chrome in many ways, but Chrome feels better and seems to render more quickly (just anecdotal, but seems to be true). I could go either way between Chrome and Safari. I used to push Firefox, but over the past few years, it feels like it's gotten heavier. Even in my VMs where I run Windows (for things like AVR Studio), I don't ever fire up IE. Ick.

  • I'm new to this whole stepper thing. Want to use this particular one to shuffle some candy pieces around. I'm using the Big Easy Driver. I'm controlling it with an Arduino (on a breadboard at 16 MHz). The pulsing routine looks like this:

    #define CLOCKWISE LOW
    #define COUNTERCLOCKWISE HIGH
    
    void stepperSteps( long n ) {
      digitalWrite( DIR_PIN, n < 0 ? COUNTERCLOCKWISE : CLOCKWISE );
      digitalWrite( ENABLE_PIN, LOW );
      n = abs( n );
      for( ; n > 0; n-- ) {
        PORTB |= _BV(PINB1); // WAY faster than digitalWrite
        delayMicroseconds( 50 );
        PORTB &= ~_BV(PINB1);
        delayMicroseconds( 50 );
      }
      digitalWrite( ENABLE_PIN, HIGH );
    }
    

    I ENAble the board, set direction, pulse using direct bit manipulation to get it as fast as possible, then unENAble the board. I tuned the current to the motor and all seems to be pretty happy.

    The BED docs say pulses should be 10 µsecs. If I do that, the motor stutters. I assume because there just isn't enough time between edges. 50 µsecs is the sweet spot I've found. Upwards of 100 µsecs or longer and the motor stutters again. When the motor stutters, I try upping the current thinking maybe it needs some help holding between pulses. That just makes the motor and the BED super hot (chip gets to 150ºF, motor is barely comfortable to hold) and generally doesn't help the motor move well at all. At 50 µsecs, the chip temperature drops to 80-ishºF.

    Anyone have a solid reason why 50 µsecs would be the sweet spot for making everything move smoothly? Just curious!

  • "Biv. Roy G. Biv."

  • Kudos to Hugo and Co.! I'm upgrading a project I did 3 or 4 years ago that had multiple ambient light sensors connected to an old-school Make Controller over UTP cable. The controller then broadcast the lights' statuses over UDP to indicate room usage via a Mac desktop menu bar app. With the Imp, which took me all of 5 minutes to get communicating to our web service, I had a prototype up and running with no extra parts: No central MCU, no more cables, no PoE... It was great. Super easy to use, easy to commission and connect to your WiFi. WAY less work than an AVR with a WiFly. Xbee was a consideraton and I do love those modules, but getting their chatter onto WiFi isn't this simple. Thanks, Hugo!

  • My suggestion for next year: Hire someone who can set you up on Amazon's or Google's cloud technologies for Free Day. Normal web hosting is useless for something like this and just frustrates your users.

  • That sucked. Second year in a row, I spent hours trying to get to the page and lost out. Not happy.

  • I love this button! Slick and fun. I posted on my blog how I upgraded it using three 3-LED SMDs and some adhesive foil to re-light the underside of the dome. It's easy to upgrade that button and put your own label on it. http://stuffandymakes.com/2011/01/08/hack-the-sparkfun-big-red-dome-button/

No public wish lists :(