Ultrasonic Sonar Project

Discussion in 'Embedded Systems and Microcontrollers' started by Hunter235711, Jul 15, 2013.

  1. Hunter235711

    Thread Starter New Member

    Jul 14, 2013
    Hi, this is my first post and I am hoping to get some helpful advice regarding a project I have been working on.

    I have been experimenting with ultrasonic audio (20-40 kHz) using a USB soundcard with a 192kHz sampling rate connected to my laptop. However, I really want to replace the soundcard and laptop with a microcontroller and some analog to digital converters.

    What I want to do is record approximately 1 second of stereo audio with a sampling rate somewhere around 192kHz. Immediately after this recording is finished I want to play back the stereo audio signal through headphones at approximately 1/10th of the original speed. This means the 1 second recording would take 10 seconds to play back.

    What kind of hardware would I need to do this?

    I am just starting out with embedded electronics and I have a Cerebot MX7 cK PIC32 development board with 128k RAM from a class I took last year. What I am planning to do is buy a pair of A/D converters and a pair of D/A converters to use with this board. Also, I may need to expand the memory some way to store the audio.

    What I don't know is
    1. Can the board I currently have do what I want it to? By this I mean with external A/Ds and could I record data fast enough without running out of clock cycles and have enough room to store it?

    2. Will I need external memory to hold the audio, and if so what kind and how much? (It seems like I will, 192samples/sec*2channels*2bytes/sample*1secondRecordTime = 768,000 bytes of data.)

    3. Does anyone have any good suggestions for an A/D or D/A converter? There just seem like so many of them out there to choose from.

    Thank you so much for your help! It is very much appreciated!