Recent content by swarfrat

I'm wanting to do some Piezo TDOA detection using a Teensy LC (if it matters). I'm planning up to about 5 piezos - 3 for TDOA and 2 others for external noise rejection. The 3 TDOA sensors are spaced 120 degrees around the perimiter of the detection zone (ie, all hits are inside). The 2 noise...

I hooked it up to pins AGND, 3.3V, and A9. Yes it's biased to 1/2 VCC but A9 reads that range anyway - it can't read negative. Raw reading shows bias reads 512 over time, as I'd expect it to. The Audio Librarie's AudioInputAnalog doc says "signal range is 0 to 1.2v" which looks about right for...

The source in the first post will do it - removing the analogread for clarity will result in the app running as expected, but never going below 10 once the mic clipped. #include <Audio.h> #include <Wire.h> // GUItool: begin automatically generated code AudioInputAnalog adc1(A9)...

Thanks for clarifying that it makes sense - I was just trying to independently verify what was going on. AudioAnalyzePeak however still seems to get stuck with a non-clearing peak value of 10 in the example if the mic clips, which does not seem to happen if I do my own analogRead & peak...

I'm hesitant to say it's the audio library hanging, but on my Teensy 3.0, I have a couple problems with this simple program (below). I've got an Adafruit MAX4466 board wired up to pin 9, running off 3.3v. If I read raw analog values, I see more or less what I'd expect. But with the peak meter...

Doh. and thank you.

Ok, still getting poor sample rates (about 345 Hz on a 96 Mhz Teensy 3.0) Here's my code: #include <Audio.h> #include <Wire.h> AudioInputAnalog microphone(A9); AudioRecordQueue rq; AudioConnection patchCord2(microphone, rq); void setup() { AudioMemory(32); Serial.begin(9600); } void...

Thanks - that's sufficient for the audio analysis portion of my project. But .. I looked at the AudioAnalyzePrint class, and besides verbage saying not to use it - I couldn't seem to get it to tell how many samples had been read. (I'd still like to have a sanity check of the resulting sampling...

I'm doing an SPL meter stoplight, and using analogRead() with a Teensy 3.0, I'm only getting about 390Hz sample rate. I've got analogReadResolution(6) and analogReadAveraging(0), running open loop for 50ms. I'm not trying to do FFT or anything super fancy - I just need to make sure I don't...

You could, but that's actually more complex if the circuit already has a teensy involved.

You're just wanting a noise activated trigger? You can just sample, rectify, filter and level trigger off that. Doesn't require anything as complex as FFT unless you want to trigger off specific frequencies.

Yes, I'm familiar with the Hall Effect, and did look at a couple Hall effect sensors I was familiar with from past projects - but nothing I was familiar with would survive hundreds of amps while measuring a couple amps. Thinking some more about the problem - I'm thinking ignoring the starter...

I'm thinking about throwing a teensy on my car battery - I have something which appears to be draining the battery, but it's not always on. (Charging, Starter, Battery all check out fine). So I want to monitor battery voltage and charge/discharge current while off in addition to while the car is...

I've been doing some more thinking, and I like the per string processing rather than just doing 2 octaves down on a summed mix. The highest frequency I'd need to detect is 784 Hz, the lowest possible would be about 110 Hz. The options I've thought of are: 1) Feed a highly clipped square wave...

I was looking to do an octave pitch shift, and I have a couple teensy 3.0's laying around. Basically this is supposed to be a polyphonic octave effect, and I'd like to shift down 2 octaves, fixed interval. My toddler son loves music and playing with daddy. He just got his first toy acoustic...