arduino/maxuino sinewave generator on digital output

My advice is to drop maxuino and any connection kits
or similar and make simple max patch and arduino sketch
to do what you want.
depending on number of piezos connected, you might need
TimerFreeTone() library instead of tone()

https://bitbucket.org/teckel12/arduino-timer-free-tone/downloads/
-----------
Since few years firmataplus exists, aiming to enable use of tone library,
but you won't find any trace of that in outdated maxuino.
There are also not really well documented maxfirmata externals
https://github.com/NullMember/MaxFirmata

and so on...

Again, dropping firmata would save you a lot of time, and at the end
maybe you'll get what you want.

+1 to that, it's really not hard to roll your own. "Exploring Arduino" is a great book.

Thank you for your answers! I'm looking at all of these. The idea is to create a composition with a lot of piezos and I can not see how to realise it directly with Arduino IDE. (I know "tone()" is pretty easy to use but seems a bit limited)
For sure it s possible to do it in max, even without maxuino. But can't see how for the moment.

If you're not set on Arduino, it might be worth looking at the Daisy platform, on which you can run Gen~ exports.

Hi guys,
I drop firmata/maxuino to use instead the [serial] object in max and the "TimerFreeTone" library of arduino. Obviously it seems much more relevant... Thanks for the advices !

I'm scratching my head now with how to send multiples variables from max to arduino. I manage to send one only with [serial] in max and with the "Serial.read" function in arduino.

I hope I'm clear enough with my explainations. Do you know how to send/receive multiples values FROM max TO arduino (I found a great tutorial about how to do the oposite but nothing about this way...)

thank you,

the optimal way to send values from max to arduino would depend
on your plan with piezos.
I mean if all would receive freq to play at same time, having same duration and volume ?
Or individual, which again could in maximum have all 3 values included,
freq, duration , volume.
here is one example using prepended IDs for 6 arduino pins,
followed by 3 values.

#include <TimerFreeTone.h>
byte inByte;
void setup() {Serial.begin(57600);} // increased baud rate if really fast data needed

void loop() {if (Serial.available() > 0) {inByte = Serial.read();
if (inByte == 'A'){int freq1 = Serial.parseInt(); int dur1 = Serial.parseInt(); int vol1 = Serial.parseInt(); TimerFreeTone(3, freq1, dur1, vol1);}
if (inByte == 'B'){int freq2 = Serial.parseInt(); int dur2 = Serial.parseInt(); int vol2 = Serial.parseInt(); TimerFreeTone(4, freq2, dur2, vol2);}
if (inByte == 'C'){int freq3 = Serial.parseInt(); int dur3 = Serial.parseInt(); int vol3 = Serial.parseInt(); TimerFreeTone(5, freq3, dur3, vol3);}
if (inByte == 'D'){int freq4 = Serial.parseInt(); int dur4 = Serial.parseInt(); int vol4 = Serial.parseInt(); TimerFreeTone(6, freq4, dur4, vol4);}
if (inByte == 'E'){int freq5 = Serial.parseInt(); int dur5 = Serial.parseInt(); int vol5 = Serial.parseInt(); TimerFreeTone(7, freq5, dur5, vol5);}
if (inByte == 'F'){int freq6 = Serial.parseInt(); int dur6 = Serial.parseInt(); int vol6 = Serial.parseInt(); TimerFreeTone(8, freq6, dur6, vol6);}
}}

// SYNTAX:
// TimerFreeTone( pin, frequency, duration [, volume ] ) - Play a note on pin at frequency in Hz for duration in milliseconds.
// Parameters:
// * pin - Pin speaker is wired to (other wire to ground, be sure to add an inline 100 ohm resistor).
// * frequency - Play the specified frequency (should work fairly well in the 100 to 15000 Hz range).
// * duration - Set the duration to play in milliseconds. Range: 0 to 65535 (65.5 seconds).
// * volume - Optionally set the tone volume level (from 1 to 10), defaults to full volume (10).

maxpatch

--------------
one could remove volume if you don't need that.

if you would prefer to send one long list containing only frequencies
which would be distributed to pins with fixed duration and volume,
things would look a bit more simple.
But then all would sound at same time....

Hi, thanks a lot for this. It seemed clear enough for me until... I tried it.

It does not work and I don't know why. The arduino led is reacting but nothing comes from the piezo.
(The wire is ok, I have sound in other ways).
I'm not sure to understand the role of [atoi] but I have to work on it.

If I understand your patch example I must have a 220hz sound during 250 miliseconds at the maximum (10) volum on the pin 3? (Refer to the first message object).

thanks again for your time!

Sorry to have troubled you with that mistake.
In Arduino code I used Serial.parseInt(); for all values
but in Max in pack 0. 0 0 I used float for the frequency,
which should be so.
So please simply replace all
int freq1 = Serial.parseInt();
int freq1 = Serial.parseFloat();
etc.
time and vol should keep parseInt
--------
I guess you know that all tone() based libs are mono,
means no matter how different outputs you use, at the end
only one sound can be generated at a time.