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Jeremy Blum

Jeremy is an Electrical and Computer Engineering Student at Cornell University. He has been building microcontroller projects since high school, from a prototype prosthetic hand with a novel control scheme, to a nerf gun that fires at the intruders and uploads their picture to the web.

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sciguy14 over 15 years ago in reply to dragonfly.67

The 220ohm resistors are for the LEDs.
The reset switch should only be able to go on one way, on the 4 pads right above the arduino logo.
The ICSP should be inserted through the 6 holes on the top, so the leads extend down, allowing it to be plugged in to the arduino
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sciguy14 over 15 years ago in reply to e14 Contributor

It depends how intense the quadracopter is going to be. 300degress/s means it can measure a rotational change of up to to 300 degrees in one second. If your copter will be moving faster than that, then you need a faster gyro.
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sciguy14 over 15 years ago in reply to e14 Contributor

Yes that's fine. Size doesn't matter, just the capacitance and the voltage rating.
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e14 Contributor over 15 years ago

My idea is a halo weapon like a assult rifle and you make it so you kan shot and aim with it
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e14 Contributor over 15 years ago

Hello sir,
can we implement a GSM module as the input to an arduino, to extract the message?
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rstiphout over 15 years ago

Hi Jeremy -

Much appreciate all your work helping out newbies.

Working with an Arduino Uno, trying out your tutorials.

Have a question about tutorial 2 :

looking at the code on version 4, with the ledLevels -

for the following:

boolean debounce(boolean last)
{
boolean current = digitalRead(switchPin);
if (last != current)
{
delay(5);
current = digitalRead(switchPin);
}
return current;
}

My question is - I don't see where the variable "last" was initialized. if this is not done, how can last be compared to "current?" [if(last != current)]

Should I read last as equal to LOW because the value of lastButton was initalized as LOW? - this coming from :
currentButton = debounce(LastButton);

If I am reading the code correctly, let me know -

thanks, Rick

ps - my hardware works as advertised in tutorial 2 - so there isn't anything wrong with the code - just my understanding the flow (!? gee - what else is new...)
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e14 Contributor over 15 years ago

Hi Jeremy,

How to rewrite or store data on Mifare RFID tags? I'm planing to use arduino with SM130 RFID module as it's claimed capable of writing data tohttp://www.trossenrobotics.com/store/p/6212-Grab-Bag-of-372-25mm-Thin-White-Disks.aspx those blank tags. There are a couple of tutorials on using it to read data (i.e. Professional Code, tigoe) but none gives a clear explanation on how to write.

Thanks
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sciguy14 over 15 years ago in reply to e14 Contributor

Yes, I'll have a video on that in the coming weeks.
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sciguy14 over 15 years ago in reply to rstiphout

boolean debounce(boolean last) is a function that takes a single parameter, that it locally refers to as "last" In the case of this program, we passing the value "lastButton" from the loop() function.
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sciguy14 over 15 years ago in reply to e14 Contributor

There's a tutorial on that here:, and I'll be doing a video on RFID tags in the coming weeks. http://www.cooking-hacks.com/index.php/documentation/tutorials/arduino-rfid
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