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Send Serial data fade LED

vvvv beta question
#1

Hiho,

I have issues fading an LED on my Arduino board using the rs232 - node.
I´m not able to realize a smooth fading of the brightness of the LED when I´m moving the faders in vvvv. The LED just stutters irregularly.
See the screenshot and the attached sketch. I also added the Arduino sketch which receives the Serial data coming from vvvv.

I have already tried to send serial data from Javascript to Arduino using the same Arduino sketch. This works without problems. Inside Javascript, I used the setInterval() - function which only wrote the data 10 times a second to the serial port.
Maybe vvvv is sending too often serial data to the Serial port??
Can I define a setInterval() are something similar in vvvv, too?

Has anyone an idea how I can fade my LED smoothly in vvvv?
In my patch I tried to set a kind of interval to the R - channel, but this does not prevent the rs232 node from writing serial data to the serial port as often as before.

Well, I know the way with Firmata (which is indeed able to realise a smooth fading), but unfortunately I can´t use it, because I´ve got a lot more things to specify in my Arduino sketch, as I´m going to distribute the incoming value over an i2c network to several slaves.

Who has an idea?

SendSerialWithIntervals.v4p (22.6 kB)
HexToArduino.ino_.txt (2.8 kB)

#2

#3

without trying to understand your particular problem… have you read through: hardware#arduino
it has pointers to literally tons of examples. do they help?

#4

Unfortunately I can´t find any solution for my issue :-(
In brief: I need to find out how vvvv can send serial data this way the LEDs on the Arduino board fade smoothly.
I have no insight in what the FirmataEncode node does, but this node realizes a smooth fading perfectly.
If someone can teach me …
I have been trying lots of alternatives for months but I´m coming back to vvvv because I can´t believe that there is no solution!

#5

hi try send you decimal values converted via spellvalue in ascii mode (byte) then send the serial to arduino .

#6

I haven’t verified that this works now since I don’t have the hardware available but my memory tells me it at least used to work fine ~months ago…

edit: noticed it relied on two plugins so added them to the zip

WishboxTwoWayCom.zip (23.7 kB)

#7

In the arduino code, the only delay I see is delay(3), so you should be able to send 333 values/second. Your patch isn’t running that fast (check that using the timing node).

If the Firmate node works for you, why not just use that and forget about the other code? I don’t know what hardware setup is, but if it is as basic as having R,G,B LEDs PWM-ing at pin 9,10,11 you can save yourself a LOT of trouble.

About your patch:

First you use a value from 0 - 255, and than you map that back to 0 - 1.

Forget what you know from DMX/8bit and stuff, keep your vvvv values between 0 and 1 in vvvv, so RGB, LFO’s and many other nodes can talk to each other without you having to use the MAP node all over the place.

FirmataCouldWork.v4p (17.8 kB)

#8

Hello wurstbrotrest,

please check this example in your vvvv directory:

girlpower\IO\Arduino\1_Arduino_DataAsStrings.v4p

It shows how to create and exchange your own simple messages with Arduino. This example smoothly fades the LED. A bit more things than you need are hapenning there, but look at the Step 2. There is a Limiter (Animation) node which limits how many times per second the values are sampled.

Does this help?

Best,
Anton

#9

Wow!
So many good answers at so little time!!
I should have asked earlier :-) I´d have saved a lot of time.

colorsound´s idea did not work for me.
beyon´s wishbox is great! There are some very useful snipplets inside. I spent the last hours checking them out.

I will check out westbam´s and robotanton´s solutions soon.
I will keep you up to date.

Until now: Thanks a lot!!

#10

hi i made you an example i just clean and puts some notes, you can do it in other ways as well. i use this way quite often.

SendSerial2Arduino.rar (9.3 kB)

#11

Yeees!
I´m the happiest!
Having tested and modified beyon´s Wishbox yesterday, I now enjoyed colorsound´s example ‘SendSerial2Arduino.rar’. I must correct myself: It is well understandable, clear and it works perfectly. It doesn´t need any .cs-plugins as beyon´s Wishbox does.
I think, this is just the right thing I was looking for!

@robotanton:
Your example is clear, too. In fact, your solution is quite similar to colorsound´s. If I hadn´t been too lazy to update to the current vvvv girlpower folder (31_2) until now, I would have seen this new example earlier!!
It´s only a short while ago, I got lost in girlpower\The Next Generation…

@Westbam:
Of course I know the way through Firmata.
In my case, however, I have to stay a bit more flexible on the Arduino side.
I can´t simply turn my Arduino-board into a brainless slave as it is the case with Firmata. Without the need the need of more flexibility I wouldn´t care about other solutions than Firmata.
But now, I´ve got it.

@all: Thanks so much for helping. This is a great thread (not even one day old).

#12

:D Brilliant!!

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