eclipse / upm

UPM is a high level repository that provides software drivers for a wide variety of commonly used sensors and actuators. These software drivers interact with the underlying hardware platform through calls to MRAA APIs.

MIT License

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Question, frequency forumla #400

Closed Emaxoso closed 8 years ago

Emaxoso commented 8 years ago

Hi, i have a question for you: in the header file "Buzzer.h" you define this constants, what is the formula that you applied for calculating the value of the frequency?

define DO 3300 // 261 Hz

define RE 2930 // 294 Hz

define MI 2600 // 329 Hz

define FA 2460 // 349 Hz

define SOL 2190 // 392 Hz

define LA 1960 // 440 Hz

define SI 1750 // 493 Hz

I'm using an intel edison

Propanu commented 8 years ago

Hi. You can use the period to to frequency formula for this: T = 1/F. Where T is your period in seconds and F your frequency in Hz. There are several calculators available online that you can use for the conversion, e.g. here. This table might also help. I think initially the notes where C4 to B5 (as per labels and frequencies listed next to them) but they were shifted up F4 to E5 because the Grove Buzzer resonates best around 2300 Hz and the original labels were not changed. Will update the file when I get a chance.

Propanu commented 8 years ago

Frequencies have been updated to match the notes defined by the header as of f850f5b7d89a2c3b8da3aaf2d35294766359dd1c. Thanks!