I have a question related to issues I'm having with an open source project I'm working on. The project is the next version of the Camera Axe for those interested. http://www.CameraAxe.com
Images: Bad Oscilloscope Image: http://www.glacialwanderer.com/_blog/blog2011/10_Oct/b_bad.jpg Bad Oscilloscope Image2 (with 5V rail and micro reset pin): http://www.glacialwanderer.com/_blog/blog2011/10_Oct/IMG_2558.jpg Good Oscilloscope Image http://www.glacialwanderer.com/_blog/blog2011/10_Oct/v_good.jpg Schematic: http://www.glacialwanderer.com/_blog/blog2011/10_Oct/ca_schematic.png
I have 5 test units and two of them don't startup correctly. If it has been sitting for more than 3 seconds I need to turn it on, then turn it off, and then turn it on again to make it work. If I just turn it on the micro doesn't initialize correctly. Three of the oscilloscope images above are the output voltages from a good unit, the bad unit, and then the bad unit with the reset voltage. The problem is that reset pin dropping to 0V after going up to 1+ V. I don't understand why that is happening, but if I remove C1 (cap between DTR and reset pin for micro) the problem goes away. I can't just do that though or I won't be able to load new programs. I did some looking an it seems that all the arduino boards use a similar cap so I'm not sure why it is causing me problems. Ideas?