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1  Using Arduino / LEDs and Multiplexing / Re: Difficulties with PT4115 dim pin on: May 14, 2014, 04:13:02 pm
For future readers:

It should work. I did the same some time ago.

The PT4115 chips are prone to over-voltage / ESD damage on the DIM pin. I've killed a couple of them. Use your multimeter and measure the resistance between DIM and GND. If resistance is very low ( < 10k or so ), then the chip is toast.

The DIM pin must be protected with a 5V1 Zener diode + resistor ( voltage clamp ). I used BZX84C_5V1 and a 1k resistor.
2  Using Arduino / Installation & Troubleshooting / Re: Uploading sketches to an ATmega on a breadboard, 8 MHz internal clock on: November 10, 2013, 07:49:21 am
If you can upload the "ArduinoISP" sketch to your Arduino board, it should work.

A blank (fresh from factory) ATmega168/328 chip will work with just 5V and GND. Don't forget a small capacitor (4.7µF or so for starters) between 5V and GND.

Depending on the FUSE settings you program, this may change and it may need an external crystal / resonator. These things are only a couple of cents, best to have at least one just in case.
3  Using Arduino / LEDs and Multiplexing / Re: How to create an RGB LED matrix using PWM on: November 09, 2013, 06:28:50 am
4  International / Deutsch / Re: Timer/ Interrupt basierte IR Analyse on: August 03, 2012, 07:34:54 am
Da hilft es nur systematisch vorgehen ;-) Alles rauswerfen / auskommentieren und schrittweise testen, bis es haengt.

Übrigens kann man auch sehr gut mit der normalen 'Uhr' des Arduino im niedrigen µs bereich messen [millis() bzw. micros()]. Ein bischen jitter bleibt über, aber für eine IR fernbedienung reicht es allemal.

Es ist schon sehr überwältigend, wieviel c++ code geschrieben werden muss, um ein bischen pin-change interrupt in eine bibliothek zu packen. Gut, es wird vermutlich portabler, ist in eine klasse gepfercht und so weiter, aber eigentlich braucht man nur ein paar register zu setzen...
5  International / Deutsch / Re: Timer/ Interrupt basierte IR Analyse on: August 01, 2012, 02:58:32 pm
Als erstes würde ich mal die ganzen serial.print geschichten aus dem interrupt code entfernen und durch das blinken einer LED ersetzen. Dann verpasse dir selbst einen klaps auf den hinterkopf.

Das senden über serial wird ab 1.01 interrupt-basiert erledigt und kann somit innerhalb eines anderen interrupts nicht funktionieren.
6  International / Deutsch / Re: DOF ?!? on: June 29, 2012, 12:06:14 pm
Wenn es keine ueberlappung gibt dann ja.

Z.B. translation / beschleunigung entlang einer achse und rotation um diese achse sind unabhaengige groessen.

Wenn man aber den kompass und das gyroskop verwendet, um die ausrichtung des objekts zu bestimmen (z.b. absolute winkelposition der vertikalen achse), dann verwendet man zwar 2 datenquellen, es ist aber nur 1 freiheitsgrad (es gibt diese achse eben nur 1x).
7  International / Deutsch / Re: DOF ?!? on: June 29, 2012, 11:46:19 am
Freiheitsgrade - nur auf Englisch, also degrees of freedom.
8  Topics / Product Design / Re: New to PCB design: Need advice. Plus low cost PCB Fab. on: June 25, 2012, 07:08:56 pm

Surely you can export an _empty_ top-copper and top-mask layer? Is there a specific reason why your mounting holes are not on both copper layers? That would solve that 'issue'.

Believe me, they don't care if layers are empty ;-)
9  Topics / Product Design / Re: New to PCB design: Need advice. Plus low cost PCB Fab. on: June 25, 2012, 06:13:52 pm
I can't see anything unusual with your gerber files. I didn't check for electrical sanity though.

If you only need a small number of boards made, have a look at OSHPARK (formerly Laen's PCB service - dorkbotpdx). Very good quality, but the boards are purple ;-) It costs 5$ per square inch for 3 boards. Everything is US-made if you should care for these things.
10  Community / Bar Sport / Re: So much stuff! on: June 22, 2012, 01:36:38 pm
I made the mistake of putting my resistors in a partitioned box.

Next time get one of the more advanced boxes. These come with a safety feature - a lid!
11  Community / Bar Sport / Re: So much stuff! on: June 21, 2012, 02:35:30 pm
You seriously need partitioned storage boxes. You instantly see what you have. And if you keep a bit of order (categorized boxes), the amount of rummaging will be kept to a minimum. What remains is a pleasant dig for parts once in a while.
12  International / Deutsch / Re: Leiterbahn Breite ? on: June 21, 2012, 02:31:19 pm
Google mal nach IPC-2221 ;-)
13  International / Deutsch / Re: Mehrdimensionales Array mittels Funktion durchsuchen on: June 14, 2012, 05:40:20 pm
Dein array is vom typ "pointer auf char". Deine funktion verwendet...
14  Using Arduino / Installation & Troubleshooting / Re: Uno Board Failure on: June 11, 2012, 04:50:04 pm
If you don't find someone with proper gear and experience, this one will be tricky to replace.

And with part and shipping costs you may end up pretty close to what 1/2 of the full board costs. And if you don't get all the bad ones in the first go you'll need another iteration. Might not be worth the trouble. Best to use the modular approach you were talking about.
15  Using Arduino / Installation & Troubleshooting / Re: Uno Board Failure on: June 10, 2012, 03:19:47 am
Please don't assume, that leads to further destruction. The pin assignments on these components are not always the same. You'll have to use the datasheet to identify which is which.
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