Hi guys, I'm new in the Arduino-world and building my first Arduino-powered gadget. I built a diy-variometer from this page: http://forum.skynomad.net/viewtopic.php?f=14&t=8333 I finished it and everything works fine. Well almost everything ;) There are two little issues:
1) The variometer sometimes beeps while laying on the table (constant altitude). I just used the Code from the link above. Hardware is also the same, connections are the same, too. Can you find the line, where this problem is located? :)
2) This is the bigger problem: I used the piezo like it's shown at the link; connected to GND and pin9. I'd like to have a louder beep from the piezo so I thought of another setup: Would it be possible to connect the piezo to the ports 8 and 9 (for example) and inverse those pins (pin8 HIGH when pin9 is LOW, pin8 LOW when pin8 is HIGH). The idea is, to create a bigger voltage (max voltage at pin9-GND is 3.3V, with 2 pins it would be 6.6V, wouldn't it?). How can I make the two pins swap continuously? I got a few programming-skills on C, but I don't know, how to set this continuing mode...(it also would be nice to know the negation-sign on Arduino).
Thanks for your help guys! Best regards