arduino data

Jan 5, 2013 at 2:54pm

arduino data

hello friends,

i am new to arduino and max.
i have a connection from arduino to max and i would like to read the digital pin (number 8 and 9)!
it works fine in max but i want this:
I have a Capacitive Sensor attached to arduino and want to show/read
the differences in my value (works in arduino serial monitor) but in max i only get two consistent values.

can anyone help me?

this is my max patch:

– Pasted Max Patch, click to expand. –

cheers flo

Jan 5, 2013 at 7:44pm

without seeing your Arduino code this is a little vague, so I suggest removing the [atoi] object in your Max patch and checking to ensure that the code is outputting the correct format (8-bit ASCII). If you’re getting readings in the serial monitor window in Arduino then that’s good; look in your code for the “sending” function:

Serial.print(xxx, BYTE);


Serial.write(xxx);//newer Arduino boards and IDE

and make sure there’s no Serial.println.

but we’d really need to see the Arduino code


study materials here:

Jan 6, 2013 at 4:28am

Agreed with Brendan, we’d need your matching Arduino code to be able to debug the issue.

Jan 10, 2013 at 4:21pm

thanks for your fast reply!
brendan ive tried it without the Serial.println but its the same.
the value stays the same if i touch the Capacitive Sensor or not!

ardunio code is from paul badger:
here it is:

int i;
unsigned int x, y;
float accum, fout, fval = .07; // these are variables for a simple low-pass (smoothing) filter – fval of 1 = no filter – .001 = max filter
int ledPin = 5; // select the pin for the LED
float nonTouched, store = 0;

void setup() {

//DDRB=B101; // DDR is the pin direction register – governs inputs and outputs- 1′s are outputs
// Arduino pin 8 output, pin 9 input, pin 10 output for “guard pin”
// preceding line is equivalent to three lines below
pinMode(8, OUTPUT); // output pin
pinMode(9, INPUT); // input pin
pinMode(10, OUTPUT); // guard pin
digitalWrite(10, LOW); //could also be HIGH – don’t use this pin for changing output though
pinMode(5, OUTPUT);


void loop() {
y = 0; // clear out variables
x = 0;

for (i=0; i < 4 ; i++ ){ // do it four times to build up an average - not really neccessary but takes out some jitter

// LOW-to-HIGH transition
//PORTB = PORTB | 1; // Same as line below – shows programmer chops but doesn’t really buy any more speed
digitalWrite(8, HIGH);
// output pin is PortB0 (Arduino 8), sensor pin is PortB1 (Arduinio 9)

//while ((PINB & B10) != B10 ) { // while the sense pin is not high
while (digitalRead(9) != 1) { // same as above port manipulation above – only 20 times slower!

// HIGH-to-LOW transition
// PORTB = PORTB & 0xFE; // Same as line below – these shows programmer chops but doesn’t really buy any more speed
digitalWrite(8, LOW);
//while((PINB & B10) != 0 ){ // while pin is not low — same as below only 20 times faster
while(digitalRead(9) != 0 ) { // same as above port manipulation – only 20 times slower!


fout = (fval * (float)x) + ((1-fval) * accum); // Easy smoothing filter “fval” determines amount of new data in fout
accum = fout;
if (store<50) {
nonTouched = fout;
if (store>50){
store = 50;

Serial.print((long)x, DEC); // raw data – Low to High
Serial.print( ” “);
Serial.print((long)y, DEC); // raw data – High to Low
Serial.print( ” “);
Serial.print( (long)fout, DEC); // Smoothed Low to High
Serial.print( ” “);
if (fout>nonTouched+3){

Jan 10, 2013 at 7:10pm

Are you still getting a variable reading in the Arduino monitor window? If so, please post a small screenshot of the readings. My Arduino chops aren’t great but it appears that this code is only generating an “on/off” transition. It’s also likely I’m wrong


May 1, 2013 at 2:45pm

sorry for not answering in a while! hadnt time for this project!

i have this readings from arduino

screen 1 – non touched

screen 2 – touched

it works fine but now i want to read this different values in max so i can start playing a video when i touch my object…thats my goal…

[attachment=222541,5523] [attachment=222541,5524]

  1. 2.JPG
May 1, 2013 at 7:33pm

here are two resources to help you on your way:

What I tend to do is use Serial.write(myValue) or Serial.print(myValue, BYTE), terminated with a Serial.println(). Delete any lines in your Arduino code that aren’t printing the actual sensor data. This will send a stream of 8-bit value(s) with no need to convert to/from ascii. It’s also quite simple to send the data in its full 10-bit resolution, but I’ve yet to find the need for it.

Then in Max use either [zl group] or [match] as Steven Miller does in his excellent didactic patch in the above thread. Also, search this forum using the keywords “arduino” “parsing multiple sensors” etc.

Keep us posted

May 3, 2013 at 12:36pm

thanks for your help guys…
i am a lot further now in the project…

now i get a good value from my arduino…if i touch my object the value gets 40 then i send a bang and want to record a movie with my webcam…
my goal is now to record a 60sec movie from my webcam and store it in a folder “xy” and play a random video from the same folder “xy” at the same time.

do you think thats possible…thanks….
thats my max project right now:

– Pasted Max Patch, click to expand. –
May 13, 2013 at 1:43am

hello max friends…

the record time works fine…i set a bang delay to trigger the stop function of the record….

now i have another problem…i want to save the records in one folder and dont overwrite it!
i want to save it as

can you help me?!!
thanks for your help…really appreciate it.
greetz from austria


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