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1  Using Arduino / Programming Questions / Re: Timer/PWM Issues on: January 29, 2013, 04:02:36 pm
I dont know if my uno is just messed up or something, but I was using pin 10 when that code killed it. I also tried 9 6 and 3, and it is all the same for me. Can anyone verify? Just use the fade example, paste in those lines, and try it on the different pins (change the default to another timer like pin 10). I just cant figure out whats going on.
2  Using Arduino / Programming Questions / Re: Timer/PWM Issues on: January 29, 2013, 11:00:21 am
Unfortunately my code loop takes anywhere from 300 - 1200 ms to complete, so it seems I need some kind of interrupt driven button detection to reliably grab button presses. Anyone know why PWM stops working when I set the overflow interrupt?
3  Using Arduino / Sensors / Re: Weatherproofing project with display for a boat on: January 28, 2013, 11:35:52 am
Thank you, I will give those a look.
4  Using Arduino / Programming Questions / Timer/PWM Issues on: January 28, 2013, 11:33:05 am
Hello everyone! I have recently started using buttons in one of my projects, and I found a nice way to poll the buttons to make sure I always catch the keypress (I got the code from adafruit) Anyway, the code involves using timer2 to poll the buttons every 15 millis. To do that it uses the following bit of code to trigger interrupts:

  TCCR2A = 0;
  TCCR2B = 1<<CS22 | 1<<CS21 | 1<<CS20;
  //Timer2 Overflow Interrupt Enable
  TIMSK2 |= 1<<TOIE2;

It works extremely well, but now none of my PWM outputs are working. I tried pins on and off of timer2 to no avail. Is it not possible to use this type of interrupt and pwm in the same program?
5  Using Arduino / Sensors / Weatherproofing project with display for a boat on: January 19, 2013, 12:58:06 pm
First off (before I forget!) Here is a link to my pictures, project files, etc...

I bought a 1970's boat for $300. I put a lot of work into it and it is finally getting to the point where it is nice. That is a whole different story you can read about here:

I am to the point where I want to start making the thing fancy. Earlier I had decided that it would cost about the same or less to use an Arduino with a cheap GPS receiver to report speed than to buy a new speed indicator (The old one was all busted up), and now I am expanding on that idea. I want my little speed reporting computer to also take care of everything else onboard the boat. I am buying a 128 x 64 LCD display and want to mount it into the dash behind the steering wheel.

In the Google Drive share I put at the top I have my project files, my eagle files, and picture etc... I plan on keeping it updated as I work on my little project, but before I get more side-tracked, the question I came here for: What is the best way to weatherproof this display? A boat is constantly exposed to moisture, and it is stored outdoors, so it has to endure the cold and the hot as well. I mainly stick to freshwater, but saltwater is not out of the question. I came up with an idea of how I might do it, but I had not found any examples of how other people have done something similar before. Here is what I was thinking: and here is the dash:

I was basically going to try cutting a window through the dash (it is basically a sheet of fiberglass on top of a sheet of wood) and leaving a bit of a lip to silicone a bit of plexiglass in place, and then screw the display in from the other side (the screen is from here: To keep water from leaching in I would put a thin layer of silicone on the exposed wood and finish it off with a plastic box of some sort attached to the back with connectors filled with dielectric grease. It might be better to have everything in one container that slides into a hole, but I am not sure where to get/how to make something like that. Anybody here have any experience with this kind of thing?
6  Using Arduino / Sensors / Re: How to weatherproof sensors on: January 19, 2013, 12:13:16 pm
Just my 2 cents... Use capacitance to measure moisture, this allows you to completely seal the unit and you don't have to use expensive metals for the tester. Also, use a decent connector and dielectric grease in the connector. The grease is the kind they use to keep the elements out of spark-plugs and buried telephone line junctions and such.
7  Using Arduino / Motors, Mechanics, and Power / Re: Severe Engine Noise on: June 22, 2012, 02:14:43 pm
 Thanks for pointing out that there may be multiple signals overlapping (I purchased a universal tach and it only actually gets a reading on rare occasions) Once I figure out what the signal is supposed to look like, how do I actually read it? I have heard of people wrapping wire around a spark plug wire, and I could try getting a hall effect sensor on the distributor, but I don't know the best/most reliable/easiest way to approach the situation.

 Thank you for the suggestion, I will give that a try. I am thinking of seeing if the engine has a voltage regulator at all, and if not, finding an aftermarket one. Between the two it ought to fix my problem.

8  Using Arduino / Motors, Mechanics, and Power / Severe Engine Noise on: June 21, 2012, 11:02:58 pm
I have a boat from 1970 that I have been fixing, and I decided that I wanted to use a GPS based speedometer, a digital tachometer, and a fuel level sensor. The boat has a MERC 1350 engine that seems to have absolutely no regard for what the stator coil is putting out (14 - 30V). I did not really consider noise at all, but it is now a big concern, as I am nearly done with my project, and when the engine starts chaos ensues.

So, I have two questions:

  1) How would I filter/regulate the output from the engine for minimum cost? That can't be good for the battery, and it is causing problems for me. (I realize this is not an engineering forum, but there are a lot of intelligent people here)

  2) What is the best method of reading the speed the engine is going at? The engine has a Tach line, but it averages about -2.6V and has a peak to peak of something like 19V if I remember. (The engine also has a "Thunderbolt" ignition coil which is supposed to have a significantly stronger spark. When I pulled the plugs the first time there were a couple millimeters of black crud on the plugs)

Thank you for any help!
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