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4681  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Software used to produce this (see topic) picture. on: August 18, 2010, 01:13:05 pm
A better question is why you want to know...? I am not sure that using a breadboard diagram to hook things up (for future reference or to show others) is necessarily a good thing (unless perhaps geared toward extreme first-timers).

It is better to get used to (and teach, if that is the point) the relationship between real parts (on a breadboard or PCB) and their relationships to a standard schematic diagram - as early and quickly as possible...

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4682  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Software used to produce this (see topic) picture. on: August 18, 2010, 01:09:58 pm
I am pretty sure its not fritzing, unless it was an older copy; fritzing usually uses images for the parts on the breadboard, so the breadboard view looks like a real breadboard with real parts (well, usually).

I think this was done with some other software - but what, I don't know...

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4683  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: I can find this on: August 17, 2010, 06:07:50 pm
Also - make sure you are running the Processing IDE and not the Arduino IDE (could be the issue?)...

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4684  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: A bunch of huge Noobie questions on: August 16, 2010, 05:56:28 pm
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shields are just stacking daughter boards, and the number doesn't matter, it is what pins they use, if two shields use the same pin they cannot be used at the same time.

The number does matter; insofar as to the amount of current each shield uses...

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you could just build a clock + keypad and have it turn on and off a FM radio via a relay, having the audio signals passing through the arduino is kind of wasteful anyway.

I can see where having an FM receiver chip could be useful; it would allow you to use the same interface to tune the stations, select (and save) presets (each person with an alarm can get their own station!), and you could even have the alarm slowly ramp up the volume of the station when the alarm goes off...among other fun things.

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I wouldn't even bother using shields, a serial LCD just uses two pins, and using cables gives you more flexibility in design.

I do agree with this; sheilds can have their uses in prototyping, but when building a "final design", you are likely to put the Arduino in as a "standalone" on the PCB along with other components - no sheilds needed or required. I think shields were one of those things that seemed like a "good idea at the time"; and for prototyping/teaching, probably so - but they make no sense in a final design (nor does the Arduino carrier board, for that matter).

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4685  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: ARDUINO vs IPHONE vs BEAGLE BOARD on: August 14, 2010, 09:23:42 pm
That was a pretty slick entry, eried; as a poster to your youtube video commented "if there were a centerline award, you would've won it"; I wholeheartedly agree! Your entry may have been slow, but it was careful - in a competition simulating "autonomous driving", that counts for more to me.

Your system is similar to one I am (slowly) working on (I am not in it for a contest, so I can take my time, I suppose), except in my case the "prototype" vehicle is larger (a Powerwheels H2), and the intent is to be able to do GPS waypoint navigation on the ground both autonomously and semi-autonomously, mainly in off-road situations. I don't have the weight or power-consumption issue, due to the size of the platform (and the final platform, depending on how the project turns out and whether I can fund it, will likely be either a quadcycle, or if I can swing it, a Polaris ORV).

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4686  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: ARDUINO vs IPHONE vs BEAGLE BOARD on: August 14, 2010, 02:59:34 am
Something I've wondered about from time to time is using an FTDI breakout and the GPIO pins on it to communicate via I2C to various parts; of course, if you really wanted to go this route, you wouldn't do that but instead tap into an I2C bus on the PC motherboard, and use the various methods and software developed for communication (mostly for monitoring, but you can send commands, too)...

Heck, nowadays there's probably easy ways to communicate over the PCI bus; you could create a very interesting multi-port controller card if you wanted to, kinda like the old days with 8255 PIA ISA cards...

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4687  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: ARDUINO vs IPHONE vs BEAGLE BOARD on: August 14, 2010, 02:39:33 am
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actually, i am just looking for a microcontroller with all sensors in it, and has "average decent" cpu and memory, i thought iphone kicked asses coz it has all the sensors in it and we dont need to buy 1200$ contract coz we can unlock it from AT&T and jailbreak it, idk what those stuffs mean, but i thought it was supposedly "like some kinda open source".

"Jailbreaking" is essentially a process by which, using various hacks and cracks one is able to take a phone that is "locked down" (in jail), and "break it out"; so that you then can load whatever software and do whatever with the system (basically, by becoming root). A standard iPhone is a fairly locked down system; I am sure that this process, which is done by most cellular providers (regardless of the phone), is meant mainly to be able to deliver a robust and stable platform for the majority of their users, while keeping them a "captive" audience; preventing competition or "non-approved" software out of the market is a bonus.

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but seems to me like using a cheap netbook PC or ITX motherboard and multiple arduinos for "slaves" to be the best solutions, but WEIGHT factor is always to be considered more for me, some kinda obsession i have with that.

By the time you need more than one slave, you are likely working on a large and complex robot; even if the robot isn't that large, if you need this kind of complexity, you might look into smaller devices for the slaves (ATTiny-class), and slave them off the main ATMega. The ATMega could be "standalone", or it could act as a communication gateway via the USB serial port to a netbook or mini-ITX board.

A desktop rover could rely on just a simple Arduino, and it would have a lot of processing power for many tasks. You could also, for example, connect up multiple ATMegas into a "multi-chip" system, and have this communicate with the ATTiny slaves, all via I2C. This would keep the size down, while still allowing for a lot of power (provided you can think modularly about the system and programming).

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cr0sh gave the recomendations tho, i think its the best recomendations ever, cool as hell, he is a real expert or more than that, i think, just like u, man, he is a "god member" as well.
check that out man, in page one.

Thanks for the feedback, but really, I make mistakes all the time, and I learn something new here every day...

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4688  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: ARDUINO vs IPHONE vs BEAGLE BOARD on: August 13, 2010, 05:11:43 pm
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ARDUINO vs IPHONE vs BEAGLE BOARD ......?

huge gaps in prices comparisons, but imagine if we want to do something "more complicated, needs speed and complete"

the IPHONE(600MHZ CPU) has LCD (touchscreen), GPS, Accelerometer (XYZ), and is way MUCH CHEAPER compared to a bundle of ARDUINO(16MHz CPU)+LCD touchscreen+GPS+accelerometer.
BEAGLE BOARD is like too expensive and dont be fooled by them saying its "open source", its not, but idk how it can be populaire enough.

as a newbie in robotics, i am confused by this, so what do u guys, the "semi" experts and experts say about this ... ?

First, you need to define what your robot is supposed to do, what it is for, and where it will operate (along with a host of other parameters) before you can determine what the controller should or will be.

For instance, if your robot is a simple desktop rover, you probably don't need the GPS (GPS doesn't work great indoors, if at all - plus, a rover is likely to be confined to an area smaller than the error percentage of GPS, making it nearly useless even if you have a signal, unless you invest in some sort of indoor DGPS system), and you may or may not need the accelerometer.

For nearly any robot, you likely don't need an advanced, high-resolution touch screen LCD. You might need a simple character or GLCD for some status info, but that's about it.

I would not go for an iphone (or any other phone) for a robot controller, mainly because of the lack of GPIO, etc. A BeagleBoard may be useful in some instances, but not all. A netbook can be useful if your robot is big enough, but you still need GPIO for interfacing.

I feel that the Arduino platform really fills "the void" - it is more than powerful enough for most robotics needs hobbyists are likely to find themselves doing; it provides plenty of GPIO, has enough memory for complex programming, plus is fairly low power to make even small desktop rovers and such feasible. Larger robots (or those that need more capabilities) can use the Arduino as a controller for the GPIO capabilities, and use a netbook PC or a Mini-ITX motherboard PC for all the extra capabilities (vision, route planning, wifi, storage, etc). Multiple Arduinos could be used as slave controller for many different tasks on a robot, especially if it is much larger than what most hobbyists would play with (see the Arduino-controlled GPS-guided combine tractor for an example).

The other parts like GPS, accelerometers, etc - all of that is "fluff" that you are better off buying as separate sensors anyhow; typically you can find them cheap (especially if you go used or surplus), and you generally want them separate so that you can place the sensors each where they would work best for the system as a whole (especially on a larger robot).

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4689  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Do you have to? on: August 13, 2010, 05:38:55 pm
No - typically, if you want to make your project more permanent, you create what is called a "standalone Arduino" - that is, you find a bootloaded ATMega168/328, put your code on it, then build a PCB (protoboard PCB, or custom etched) that has the ATMega on it, connected to just the parts for your circuit, plus the support components for the Arduino operation (resonator or crystal/caps, voltage regulator if needed, USB if needed - though most just put header pins on and attach an FTDI breakout board or cable). The "metal breadboard" you saw was probably a solderable protoboard/perfboard PCB - this is what you use. It is kinda like building your own Arduino carrier board for the ATMega (because really, that's what you are doing), but you don't need all of the extra stuff (like headers and such for wires), you just build connectors for those pieces, or solder the wires (like from sensors, switches, whatnot) onto the protoboard and hook them up to the pins on the ATMega.

Something to note, though - DO NOT SOLDER THE ATMEGA TO THE BOARD. Install it in a DIP socket; if something should happen where you need to replace the chip, it is easier to pry it from a socket than to attempt to remove it after soldering it.

Also, look for protoboards that have thru-hole plating; they're more expensive (and harder to find), but the contruction will be much sturdier than ones that just have pads. If you can't find them, then try to find ones with pads on both sides, and solder the parts from both sides; they won't be as strong, but they'll work OK. The "flimsyist" ones you will find (still, if it is the only option - and sometimes it is - use it) have pads on one side of the board only.

Hope this helps your understanding...

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4690  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Arduino Manual on: August 10, 2010, 04:43:45 pm
There's also this:

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1247637768

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4691  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: How many volts can a typical LED take? on: July 28, 2010, 11:28:19 am
Something I find curious is why people who are beginners with electronics think that microcontrollers are the place to start?

I first really learned electronics from a tech school here in Phoenix, Arizona; we didn't use microcontrollers, but we did do interfacing with computer buses, which is virtually the same thing (albeit a more expensive issue if you -don't- use resistors on your LEDs; actually, there was usually a buffer IC used somewhere in there).

However, we didn't start with interfacing; our first few weeks was spent mainly reading and understand voltage, resistance, current, and Ohm's Law; then we got to assemble a multi-meter (analog - we learned on analog Simpson meters, and only later got to use digital bench meters). Things scaled from there.

We didn't do anything with digital interfacing until about 6 months into the year-long course; at that point we started playing with interfacing using the ISA bus (8255 cards and such); then three months after that, interfacing with the bus on an Amiga (at the time, the Motorola 68000 series was the "controller" of choice in industry, from what I understand).

We certainly didn't start there, though. Now, I understand that a microcontroller and its cost are nothing like a full computer or microprocessor; certainly if you "blow something up" on the microcontroller, its not the end of the world. However, if you do it often enough, not understanding the principles - unless you are really determined and have some cash (because dead microcontrollers do add up in costs) - you're going to get frustrated and move on...

So, why aren't we encouraging beginners to flash LEDs using cheap parts (ie, discrete transistors and/or 555 timers), where they can "blow things up" without worrying about costs so much - and also where they can learn the basics of electronics that can then be applied to later and more complex projects?

I know some people will have the "knack", or will be able to struggle through no matter the cost or time needed; these individuals would succeed no matter what the path. There are others, though, who struggle because of the costs, and the lack of understanding, who still want to learn, but can't afford to make the same mistakes as they learn. So - why does the community (hobbyist electronics) continue to push the concept (not directly) that microcontrollers are easy and anyone can get them to work - when the truth is much different?

I can't tell you the number of times I have seen people on this forum (and others) who seem to think a microcontroller (or transistor, or voltage regulator, or...{insert your part here}) is a magic "plug-n-play" box, akin to Lego (indeed, sometimes I wonder if this is where some of the attitude and ideas come from!). Without the understanding of what is actually going on, these people likely will end up frustrated, surrounded by a bunch of burnt-out parts (literally burning their money!).

I think a better solution is needed; I think the Arduino community could come up with it. Perhaps a tiered online learning scheme, with sections that start with the basics (Ohm's Law, using your multimeter, how to solder), and advance up the tiers until you get to microcontroller interfacing. There ultimately also needs to be a "real FAQ" document or system, that details all the little quirks and such, and what they mean, or how to do certain things, etc - those items that we seem to answer here every day, over and over and over (and over!)...

/rant over
4692  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: How many volts can a typical LED take? on: July 27, 2010, 05:03:52 pm
You have to limit the current with a resistor; otherwise I think they can work at nearly any voltage...
4693  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Buying components from eBay? on: July 23, 2010, 10:24:05 am
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Anyone ever use an Arduino clone from here?


I don't think I would have a problem with an Earthshine device; they have provided the community with one of the best "beginners guides" to the Arduino I have seen so far (for free online!) - as well as as a starter kit that goes with it (you pay for the kit, of course) that includes parts and such to complete the "course" in the guide and learn about how to properly use the Arduino.

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4694  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Buying components from eBay? on: July 22, 2010, 06:29:34 pm
I've never bought potentiometers, but I did buy a batch of white LEDs from a guy who goes by the name "Asia Engineer"; he shipped quick, and had good communication, and his prices were fair. The product was as described, and the LEDs work fine.
4695  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: Some help with an arduino printer! on: August 04, 2010, 11:24:44 am
Hektor's home page:

http://www.hektor.ch/

Jürg Lehni's homepage (Hektor's creator - plus information on a different machine, he calls "Rita"):

http://www.scratchdisk.com/

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