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76  Using Arduino / Audio / Re: FHT Issue on: May 31, 2013, 01:56:13 am
you could also just try getting rid of the cli(); line, and see how much slower it actually runs.  it might work fine for your application.  or use the beta version of ardiuno which didnt have that issue (arduino-0022).
77  Using Arduino / Audio / Re: How to buffer audio? on: May 19, 2013, 08:06:27 pm
if you just want to pass audio through the arduino, this is the best sounding way to do it:

http://wiki.openmusiclabs.com/wiki/MiniArDSP

it gives 10b audio at 32ksps.  there isnt a lot of time left processing, but simple effects can be done.  as far as buffering is concerned, the 2k of memory will only give you 64ms of buffer time at this sample rate.
78  Using Arduino / Audio / Re: Can someone recommend a good audio analyzer? on: April 18, 2013, 10:34:21 pm
it has markers that you can move along the trace to get values, and i estimate SNR and distortion from these, but you can also save the data and then do the real number crunching on it.  i also have a good sine generator that i use in conjunction with it to do intermodulation distortion and the like.  you can probably generate a decent sinewave with your soundcard as well.  its definitely not a complete plug and play solution, but it is free.
79  Using Arduino / Audio / Re: How to determine minimum bits per sample? on: April 18, 2013, 10:19:04 am
number of bits per sample is totally up to you, but the more bits the better it sounds.  you can calculate the theoretical noise floor for a set of bits via the following equation:

SNR = ((number of bits) x 6.02) + 1.76
80  Using Arduino / Audio / Re: Can someone recommend a good audio analyzer? on: April 18, 2013, 10:12:07 am
if you just need a spectrum analyzer, "spectrum lab" is freeware, and ive been very happy with it.  it can take in external audio from a soundcard, or work on saved wav files.
81  Using Arduino / Audio / Re: Problem: Custom PWM frequency interferes with SoftSerial on: April 05, 2013, 02:04:56 pm
timer0 is used by arduino for a lot of different things.  i would suggest switching your pwm to timer1 or timer2.
82  Using Arduino / Audio / Re: analog audio in to PWM audio out on: April 01, 2013, 11:49:22 pm
if you take a look at the circuit here:
http://wiki.openmusiclabs.com/wiki/MiniArDSP

you just need to put a guitar preamp before it.  a simple opamp circuit with gain of 100 would be fine.
83  Using Arduino / Audio / Re: analog audio in to PWM audio out on: March 26, 2013, 10:40:52 pm
i have a sketch up here:
http://wiki.openmusiclabs.com/wiki/MiniArDSP

sorry, no sound samples yet.
84  Using Arduino / Audio / Re: analog audio in to PWM audio out on: March 26, 2013, 04:12:02 pm
yes, its primarily for doing guitar/voice effects on the cheap.  but, the pwm side is just a generic setup routine to configure the pwm for various data rates and bit depths, so that can be used for any audio application.
85  Using Arduino / Audio / Re: analog audio in to PWM audio out on: March 25, 2013, 06:03:56 pm
it can output .wav, but there isnt an SD card reader setup for it yet.  so if you have something that can read SD cards, you can use the PWM to output it.  this is what the simpleSD does.
86  Using Arduino / LEDs and Multiplexing / Re: Reading multiplexed data in Pd on: March 24, 2013, 05:09:56 pm
i must be confused about how analogRead() works.  i thought you put in a number, and that was the pin it read.  so analogRead(1) reads the first pin, analogRead(2) reads the second pin, and analogRead(16) reads the 16th pin.  i dont know exactly what your circuit looks like, but i am assuming you have a mux which funnels all your inputs into a single analog input pin (if you had 16 analog input pins, you wouldnt need the mux).

your for() loop increments i from 1 to 16.  therefore you are reading in analog from pins 1 to 16, but there are no pins above 8 on the chip you are using.

Code:
 for (int i = 1; i < 17; i++) {
    digitalWrite(CONTROL0, (i&15)>>3);
    digitalWrite(CONTROL1, (i&7)>>2);
    digitalWrite(CONTROL2, (i&3)>>1);
    digitalWrite(CONTROL3, (i&1));
    unsigned int mod = analogRead(i);
    muxarray0[k++] = mod & 0x007f;
    muxarray0[k++] = (mod >> 7) & 0x0007; // in order to get 0 - 1023
  }
87  Using Arduino / LEDs and Multiplexing / Re: Reading multiplexed data in Pd on: March 24, 2013, 03:24:12 pm
why is it analogRead(i) below?  there are only 6 analog ins, and this will make it count up to 16.

Code:
   digitalWrite(CONTROL3, (i&1));
    unsigned int mod = analogRead(i);
    muxarray0[k++] = mod & 0x007f;
88  Using Arduino / Audio / Re: analog audio in to PWM audio out on: March 24, 2013, 03:20:31 pm
the ports are different between the mega and uno (what pins map to what functions), so those need to be changed.
89  Using Arduino / Audio / Re: Spectrum analysis on: March 19, 2013, 01:42:42 pm
try changing serial.write to serial.println

the data is currently coming out in binary and not ascii, so its hard to read.
90  Using Arduino / Audio / Re: WavePro Shield - Beta Testers wanted on: February 27, 2013, 02:49:06 pm
bootloaders are a pain, and you will be faced with the added layer that your target is not an arduino, so the code will have to written in some other interface anyways. honestly, once youve put the dsPIC on there, its unclear what the arduino is needed for.

out of curiosity, what was your decision making process for choosing between the dsPIC and a micro + codec?  the micro + codec option would be cheaper and allow for better sound quality, and 16b ADC.  but, it is not as flexible, and cant do a lot of audio processing.
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