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11 years ago.
Problem writing data from ADC to a file
Hi
I am trying to get audio data using microphone and write it to a local system file in mbed. i have to use this data for occupancy analysis. I am getting some values through the ADC but when i write data to a local file system in mbed the mbed connect/disconnects from the system and i can not actually see what is written inside the file.
Why is this so ?? the problem resolves if i put a delay in writing the file.
Also anyone can help me how to process the audio data from the microphone to make it meaningful i have to use it to decide if someone is present in the room or not ?? how can i do it ?
1 Answer
11 years ago.
See the documentation of local file system: When you use it locally it disconnects from your PC to prevent both writing at the same time, corrupting the entire thing. Your PC also only reads data from a USB disk once, if the mbed then changes the data and the disk is not disconnected + reconnected your PC will never notice there is new data.
To check if someone is in a room you could start by simply calculating the amplitude of the received sound.
Thanks Eric for your answer but what should i do if i have to write data to a file at a fast speed. The data may have been written on the local file system but what happens as i connects the mbed with my laptop as the code is also running inside it so the data starts to be written instantly
posted by 04 Nov 2013