Show Posts
Pages: 1 2 [3] 4 5 ... 15
31  Using Arduino / General Electronics / Re: Resistor Jumpers on: May 02, 2013, 01:23:51 pm
Huh?
32  Using Arduino / General Electronics / Re: Synaptics T1004 trackpad issues on: April 25, 2013, 03:12:31 pm
It was quite a while ago so I don't remember the details, but it was an IDE version between 0018 and 0022 I think.
33  Using Arduino / General Electronics / Re: Synaptics T1004 trackpad issues on: April 17, 2013, 12:01:27 am
I have a similar synaptics trackpad with the same pinout. It worked flawlessly with the ps2 library when I last tried it.
34  Using Arduino / General Electronics / Re: Why are real-time clocks always 32.768khz? on: April 12, 2013, 12:04:25 pm
I once heard somewhere that a specific natural occuring shape of crystal would oscillate at exactly 32.768 khz. Don't know if this holds any truth though
35  Using Arduino / General Electronics / Re: Multiple parallel secondaries for higher current on: March 20, 2013, 07:05:10 am
I probably should have mentioned that I'll be winding the secondary myself, so there will be no confusion as to which side of the winding is where. I just wanted to check if this was even possible, as it's much easier to wind several thin coils than it is to wind one very thick coil.
36  Using Arduino / General Electronics / Multiple parallel secondaries for higher current on: March 20, 2013, 05:51:33 am
Probably a simple question, but I can't wrap my head around it. Lets say I have a transformer with 2 identical secondary windings wound in the same direction. Can I connect them in parallel to double the current they can handle? Is this essentially the same as using one winding of double the thickness? It just doesn't seem right because the wires are insulated from each other except for at the ends, but google suggests that it's possible.
37  Using Arduino / General Electronics / Re: How to measure chip (or other component) temperature? on: March 08, 2013, 12:57:32 pm
I guess regular old thermal grease would work. Thermal exopy if you want a permenent contact. But either way, thet will be package temp, not die temp. Maybe with a bit of math and the thermal conductivity figures in the datasheet it would be possiblr to get an accurate measurement
38  Using Arduino / General Electronics / Re: Will 3.3V for a ATMEGA16U2 allow it to create a PC compatible USB port? on: March 05, 2013, 12:03:01 am
Yeah, it should work. Take a look at section 20.3 for proper connections
39  Using Arduino / General Electronics / Re: Will 3.3V for a ATMEGA16U2 allow it to create a PC compatible USB port? on: March 04, 2013, 03:29:09 am
Take a look at the datasheet, it talks about different methods for powering the thing if I remember correctly. Various voltages, powered from USB, powered from external source, etc.
40  Using Arduino / Project Guidance / DIY solder mask on: February 27, 2013, 01:08:16 am
Has anyone tried making their own solder mask for homemade PCB's? I'll be using some 0.5mm TQFP packages on an upcoming project and it would be nice if I could get some sort of solder mask between the pins to reduce solder bridges when drag soldering. So far my best idea is to spray the whole board with high temp spray paint and scrape away the paint on the pads with a knife. Alternatively I've seen high temp. felt tip markers which might be less messy. Does this sound feasible? Does real solder mask have some special property which makes it repel solder? And, no, I'm not interested in making a stencil and using UV curable paint.
41  Using Arduino / Project Guidance / Re: Analog Comparator Interrupt on: February 25, 2013, 03:46:48 am
Typically arduino code doesn't have functions for low level stuff like this. You'll have to use good old avr register writes.
42  Using Arduino / Displays / Re: Maximum touchscreen voltage on: February 24, 2013, 07:26:27 pm
Yeah it surprised me too when my first one got shorted. I just redid the less-than-adequate solder job and the problem seems to have gone away; must have been flux residue. However on my first touchscreen the solder job was perfect, yet the short didn't go away over time. Weird.
43  Using Arduino / Displays / Maximum touchscreen voltage on: February 24, 2013, 06:24:31 am
What is typically the maximum voltage I should apply between y+/y- or x+/x- on a resistive touchscreen? the resistance is about 300 and 500 ohms for x and y, respectively. I'm asking because I seem to have broken my first touchscreen by using 3v. The resistance between x- and y- became 100 ohms when the touchscreen wasn't pressed (it should have been infinite ohms). I just got a new touchscreen and was also using 3v when the same thing happened. If I disconnect the power and measure resistance it rises up to ~100k over the course of 30 seconds, so it might be something else. Is 3v way to much for the touchscreen? I'd like to drive it directly from an MCU output.
44  Using Arduino / General Electronics / Re: Hacking RC car to make a child happy - magic dust escaped from board. on: February 20, 2013, 02:37:40 am
I think it would be easier to just buy some transistors which can handle the voltage and solder them in instead
45  Using Arduino / Programming Questions / Re: Converting a byte string to its equivalent byte value on: February 18, 2013, 04:32:41 pm
You're right, an int is 2 bytes. However it probably work the same for most purposes. Now, understand that I never actually learned C (I just picked up what I needed), but I think you can do something like
byte b 〓 atoi(chars); or maybe
byte b 〓 (byte) atoi(chars); and it will be legal (or at least compile). Don't take my word for it though. I don't have a computer here to test it.
Pages: 1 2 [3] 4 5 ... 15