Member #86519

Member Since: October 18, 2009

Country: United States

  • Does any one know why the WiFly would halt on "client.println("? I tried to tweet via wifi and it will establish a connection to my network, it will connect to the client and then halt on "client.println". So I tried the example provided by the WiFly Library (Arduino 1.0), "WiFly_WebClient_Faster" and found the exact same result.

    Do I need to change firmware update on the WiFly or something? I'm not sure why its doing this.


  • What is the conversion for the Current sense to read amps on the Arduino?

    This is what I calculated, but its way way off!

    V=ADC_steps * (5/1024)

    I = V/1.5kOHM

    I = (ADC_steps * 5)/1024)/1500

    I = ADC_steps/307200

    But what I measured is way way off...

    Through trial and error I found the constant to be 30.56... However I don't know how accurate that is because I measured the current with a MultiMeter.

    Is it me or is there a mistake in the data-sheet? shouldn't Rsense be 1.5ohm instead of 1.5kohm... which would be 30.72 for the constant?

  • If I use this to connect a 3.3V device to a I2C bus, do I still need to insert pull-up resistors? I noticed that it has 10k pull up resistors on each side.

    I'm connecting the HV side to my Arduino and as far as I know I'm supposed to connect 1.5k pull ups to 5V, do I need to?

    What pull-up resistors would I need on the 3.3V side if any?

    See I'm able to receive perfectly, but I can't request data. The onRequest ISR on the Arduino does not run. I want to know if this could be a problem at the physical layer. Also the 3.3V comes from the Arduino's regulator and not from the device's 3.3V regulator. As long as all the grounds are connected together it should be fine right?


  • Good Stuff!

  • Yeah, I just unsoldered the switch and replaced it with a piece of wire. I will let you know if the traces survive the maximum current of 4.8A.

    I'm sure that the 5V regulator will not like 4.8A being drawn, besides I have a Programmable BEC that can source up 20A @ 6.0V. If I melt the traces I'm soldering a thick piece of wire over all the VCC and GND pins and connecting them to the BEC directly. As for the servo signal, it shouldn’t take “any current” as far as I’m aware their circuitry is CMOS based. It has to be if the idle current is rated to be 8.8mA.

    Sparkfun should put a selector jumper instead of a flimsy switch ;)

  • I'm guessing that the selector switch on this board does not like excessive current. I have 15 servos connected to it, I made a 90 degree offset mistake in my program which caused all 15 to stall simultaneously on my robot and next thing smoke pours out of the switch and it all stops.

    I have: 8 HS-645MG - Stall current of 450mA ea. 3 HS-488HB - Stall current of 180mA ea. 4 HS-422HB - Stall current of 180mA ea.

    Total stall current of 4860mA, I'm guessing the switch is rated around 1A. lol

    Any suggestions of what I should do instead?

  • I think you have a typo...
    •100x - 2.5x10mm -> •100x - 2.5x100mm
    In the picture it sais •100x - 2.5x100mm

No public wish lists :(