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Discussions on the software and hardware for Atmel's STK standard.
#181228
I am designing a pitot tube for project. If you're unaware, a pitot tube simply measures windspeed based on static pressure.

So, I have my pressure transducer connected to the ADC0 port on an ATmega32 chip. I can get the ADCH value and convert it to a string using itoa(...) and it displays fine to my LCD. However, when I try to use the ADCH output and multiply it against some constants (doubles already defined) then convert it to a string using dtostrf(...), it either displays 00's, or a bunch of gibberish.

I guess my question is this:

if I wanted to use the ADCH output and multiply it by 1.1 and display that value on the LCD, what the hell do I need to do? I know exactly how to display a string to my LCD, so it has to be an intermediate step that is causing me problems. Any ideas AVR gurus?