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1  Using Arduino / Microcontrollers / Re: PROGRAM FOR LED BLINKING IN ATMEGA2560 on: August 03, 2013, 08:34:10 am
http://cappels.org/dproj/simplest_LED_flasher/Simplest_LED_Flasher_Circuit.html
2  Using Arduino / Project Guidance / Re: A Mini Piano on: July 20, 2013, 08:22:03 am
http://www.phy.mtu.edu/~suits/notefreqs.html

Remember, there are 13 keys in each "octave". The sharps and flats allow you to play in any key without re-tuning.

That table should do it! Although I don't think you can use float values in tone(), so if you care about having it properly in-tune, you may need another approach. If not, just bang in the closest value rounded up or down to suit, and hope for the best.
3  Using Arduino / Project Guidance / Re: A Mini Piano on: July 19, 2013, 02:28:38 pm
You're going to need at least 13 buttons if you want to play anything interesting smiley-wink
4  Using Arduino / Audio / Re: Velocity Sensitivity with non-MIDI Keyboard on: July 18, 2013, 03:31:33 pm
The "time between break and make" method of velocity sensing described here is really common, especially in high-end keyboards. I've seen it in almost everything I've taken apart (but then, of that vintage, almost everything used the Yamaha FS mechanism or some ripoff of it).

Other suggestions already posted seem to be right on the money, or very close to it... just had a look at an old service manual for an instrument time forgot and it seems very similar to how the big boys do it except you won't have multiple processors all doing different jobs and having to tell the main one what they're up to smiley-grin So hopefully, a much simpler task.

5  Using Arduino / General Electronics / Re: I can lite an LED, but not a 3v flashlight bulb?? What is going on? HELP!!! on: July 18, 2013, 01:04:59 pm
Isn't a flashlight bulb going to draw massively more current than an Arduino pin can source? I would stop doing that if I were you, and switch it using a transistor instead.
6  Development / Other Hardware Development / Is the MCS-96 family worth bothering with? on: July 18, 2013, 12:05:16 pm
Having pulled the giblets out of quite a few old synthesizers in the past, I see things like the i8095 pop up quite a bit and after having poked around a datasheet I wondered if it might be worth learning a bit more about them.

As an example of what I was thinking about, I once got rid of (stupidly) a banged-up Roland S50 Sampler which was too wrecked to use. Acquired it for basically pocket change intending to restore it, but never did. Reading the service manual for it made me wish I'd kept it. I'd essentially have a complete single-board computer with bucketloads of RAM, FDD controller, TMS3556 display processor, and other goodies as well, with all the complicated things like address decoding logic already done for me and a lovely service manual for reference. The main cpu (or mcu, I suppose, more accurately) looked like a beast for it's time as well... the whole thing in general gives me the retro-horn.  smiley-twist

Do you guys think it'd be worth keeping an eye open for another pocket money piece of shit to pull apart and mess around with? Anyone know of any free tools for working with this processor family? I am currently googling in another tab but if someone already knows, that'd be great!

Not sure if this should've gone in device hacking or not... please move if appropriate  smiley-wink
7  Using Arduino / General Electronics / Re: Shift Register that can give me more than 8 pins ? on: July 18, 2013, 11:54:31 am
If you want to save space you could always use SMD ones for your final design... those packages aren't very challenging to solder and you can stuff a LOT of them in a small space.
8  Using Arduino / Audio / Re: Drum Sequencer/Sampler - 12-bit 8 Channels - One Arduino? on: July 14, 2013, 08:52:38 am
Should be possible! A single '644 is doing this:



Although the AVR has been overclocked to bollocks... I was thinking of buying a Due myself for audio tinkering, seems like it has more than enough guts to achieve the task, the hard part being the programming!

9  Community / Bar Sport / Re: RFID on: June 28, 2013, 08:52:28 am
Isn't everything wide open for abuse? I once saw a TV documentary on card-skimming at ATMs (those fake covers criminals put over the machine containing their equipment), and when we got to see a clip of the fake panel being removed, I distinctly remember red and blue solder mask on some rather familiar looking breakout boards...  smiley-roll

I plan to opt out of contactless payment until it's literally forced upon me... not necessarily through security fears but more because it's technology I just don't need.
10  General Category / General Discussion / Re: ARDUINO + PHP on: June 19, 2013, 06:52:05 am
I know I'm being picky here but shouldn't heart rate be an 8-bit int rather than a float? Resolution of 0.1bpm seems unnecessary and if it goes above 255 an alarm rather than a precise reading ought to suffice  smiley-wink Same goes for values below zero.
11  Using Arduino / Displays / Re: Interfacing a removed Mobile phone camera on: May 29, 2013, 06:39:19 am
Do you have a datasheet, or even a real part number for this camera yet?
12  Using Arduino / Project Guidance / Re: Take HD photos and save to SD card on: May 22, 2013, 12:28:41 pm
You don't need an arduino to do this, just a digital camera  smiley-razz
13  Using Arduino / General Electronics / Re: How to expansion I/O? what's a good and cheaply way using AT89S52? on: May 22, 2013, 12:23:11 pm
Couldn't you also map some 82C55's into the external bus? If you wanted to keep any serial interfaces free for other purposes, you could use as many of those as you have free address space and end up with more I/O than anyone could ever want smiley
14  Community / Bar Sport / Re: Fundawear?? on: May 07, 2013, 12:01:55 pm
I can't see that being very interesting for the male...

Unless that male is Photonicinduction. "Let's crank 'er up on the variac til she pops!"
15  Using Arduino / Project Guidance / Re: Smallest AVR that can handle FFT? on: May 06, 2013, 03:04:11 pm
If that's all you want it to do, you don't even need to use a microcontroller. A long time ago I built a circuit from some project book the name of which escapes me, that flashed LEDs according to the peaks of different frequencies using a few op-amps and some discrete components. As I recall, it wasn't all that complicated, and a piss-load easier than writing code. Of course if you need to do any intelligent decision-making other than just blinking lights, ignore what I just said :p but don't throw a micro at a project that doesn't need one.
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