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1  Using Arduino / General Electronics / Re: Problems using a logic level shifter on: November 09, 2011, 03:58:44 pm
So there's no way it can work with the 5v Arduino Pro?
2  Using Arduino / General Electronics / Re: Problems using a logic level shifter on: November 09, 2011, 02:41:13 pm
I'm just using the LED for testing out the board just to make sure it's working. I had it lying around but remembered not being able to use it with an Arduino Pro (5v) project I worked on last year. The goal is to use this with that same (now unused) Arduino Pro 5v, but if I have to also power it with a 3.3v that won't really help anything...

If I'm understanding correctly, what you're saying is that I also need to power the board with a 3.3v supply? Right now I'm just powering it using the 12 pin from my Uno to the DIR input on the board.

I know that the resistor is way too big, I also tested it out with a much smaller one, but still had the same problem.

Thanks for the help,
Jeff
3  Using Arduino / General Electronics / Problems using a logic level shifter on: November 09, 2011, 12:36:14 am
I'm having some issues getting my logic level shifter from NKC to work properly, and I'm not sure I really understand why it's working the way it is. I have this one http://store.nkcelectronics.com/5v-to-33v-logic-level-shifter-bo.html

I'm just blinking an LED, but I'm getting weird dimming issues when it shifts voltages. It almost looks like it's not getting all the power running after it converts down to 3.3v and sometimes it looks like it's not turning all the way off. It's running on the standard Blink example in Arduino and using pin 12 to power the board. Setup is as follows:

12 (HIGH) -> DIR
13 -> A0
B0 -> 10k resistor -> LED -> GND
GND -> GND

Any ideas?
4  Using Arduino / Project Guidance / Re: Motion sensor light switch modification on: June 09, 2011, 02:32:04 pm
Great, thanks for the help. I'll see if I can find a PIR switch at a hardware store to take apart, then, and test it that way. Also, when you say to connect the output to 5v through a 10K resistor, is that hooking it up through a wall wart / DC power supply?
5  Using Arduino / Project Guidance / Motion sensor light switch modification on: June 09, 2011, 09:22:08 am
I'm looking to add a circuit with some Arduino additions including a to an installed wall motion sensor switch. Has anyone used a wall switch as the basis for a project before that they might be able to shed some light on how to attach to it? At the most basic level just having access to the power output from the switch being on or off is what's needed, though potentially accessing the timer later would be handy.

I'm having a bit of trouble finding a description of how to do this and don't have a switch I can disassemble before starting. Thanks!
6  Using Arduino / Storage / Re: SD Card initialization issues with SD.h on: February 06, 2011, 12:27:32 am
Well I figured out how to change the SPI settings and that did not fix the problem. I also tried a few different resistor setups on the voltage divider, and that didn't help either. I did verify that everything was working with a 3.3v input by hooking that up to my Uno board... so I ordered a logic level shifter board (not requiring an upper and lower voltage) that should fix things.
7  Using Arduino / Storage / Re: SD Card initialization issues with SD.h on: February 04, 2011, 03:19:40 pm
fat16lib:
So how exactly would I get this working then? I got the resistive divider set up and am still having no luck with the setup. I have a brand new 2GB PNY MicroSD card I'm using, but how would I go about checking on whether or not this would work. The logic level converter isn't going to work in this setup because I only have one power source: the 5v coming in from the Mini Pro. I need to have this working by the 11th, so the quicker the solution, the better.

[Edit 17:04] Do I need to somehow change the SOFTWARE_SPI setting for the SPI mode rise? I'm not sure how to get this changed effectively, so any help is great. Thanks!
8  Using Arduino / Storage / Re: SD Card initialization issues with SD.h on: February 02, 2011, 11:12:45 pm
Great, thanks for the help. I've got the parts to try for a resistive divider, so I'm going to try that route first.
9  Using Arduino / Storage / SD Card initialization issues with SD.h on: February 02, 2011, 12:56:32 pm
I have a circuit all hooked up with a Pro Mini and accelerometer using a MicroSD breakout board (http://www.sparkfun.com/products/544) to record data using the SD.h library. Everything was working fine up until everything was soldered together, and also worked testing the circuit on an Uno. Now I'm beginning to suspect (probably correctly) that the board isn't recognizing the SD hookup because it's a 3.3v and my Pro Mini is a 5v board.

So two questions..
1) What's the best way to fix this?
2) Why would it have worked fine when it was hooked up before and during testing on my Uno?
10  Forum 2005-2010 (read only) / Interfacing / Re: Powering Arduino from a power tool battery on: January 12, 2011, 02:43:24 pm
jlucianai, I've been looking at the articles from here: http://www.thebox.myzen.co.uk/Tutorial/Power_Examples.html

I don't have any prior experience with this sort of thing, so will that mean that I'll need to include a heatsink on the regulator? I'm not entirely sure what this will entail smiley Or, is there some sort of additional voltage regulator or rudimentary power supply I'll need to create? There should be around 4-5 sensors attached to this that will need to be powered, including a 3 or 4-axis accelerometer.

Thanks for the help!
11  Forum 2005-2010 (read only) / Interfacing / Powering Arduino from a power tool battery on: January 12, 2011, 12:27:53 pm
I'm looking to power my new Arduino project from a power tool battery. Right now I have a few options ranging from 3.6V to 9V batteries. Is there anything that I should watch out for before trying to hook up the battery directly to the board? Ideally I'd just like to hook up the board to the terminals on the outside of the battery with minimal modding.

Thanks!
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