> If it is a messaging issue using the raw slip packages as described here 
> sounds promising:

Just to be clear: the MIDI style approach is already a functioning protocol and 
doesn't require SLIP packages, because you can work with the raw serial data. 
However, you could *instead* use raw SLIP packages, which is very similar in 
the way you handle values with higher resolution (bitshifting). advantage: 
8-bit data instead of 7-bit. disadvantage: slightly more complex because of the 
escape characters. 

Again the link for an bitshifting example: 
https://lists.puredata.info/pipermail/pd-list/2016-06/115160.html 
 
 

Gesendet: Donnerstag, 16. Juni 2016 um 17:35 Uhr
Von: "Rick Snow" <ricks...@gmail.com>
An: pd-list@lists.iem.at, "Christof Ressi" <christof.re...@gmx.at>
Betreff: Re: Pduino sysex vs. OSC advice

​Thanks again Christof for pointing me in a promising direction.  I have been 
working with the OSC tagging via slipenc and slipdec.
 
As of now I have fairly reliable communication between PD and the Arduino 
sketch using a version the patch you provided.  I am able to reliably send 
messages and the sketch responds as I expect most of the time.  However, when 
sending several faders simulaneously I get some glitching.  Right now I am 
wondering if it has something to do with using OSC instead of the raw slip 
packages.  I do get this message in the pd console but I'm not sure that it 
relates to the glitching: "slipdec: input packet longer than 1006" 
 
I've included the pd patch and the arduino sketch if anyone wants to take a 
look. these work with a WS2812 led strip.
 
If it is a messaging issue using the raw slip packages as described here sounds 
promising:
 
"You can also make your own simple protocol where you define a certain 
character to signify the start or end of a message. But how do you know if it's 
not part of the data? SLIP uses escape sequences to handle this case. Two 
alternative solutions:a) work with fixed length messages and count bytes (not 
very safe)
b) reduce the range of possible values for your data (e.g. 0-127, like MIDI) 
and reserve the rest for addressing (128-255). If you need a greater resolution 
for your values, just break them up into several bytes. This way, sending a 
single 16 bit integer would take 4 bytes (address, bit 14-15, bit 13-7, bit 
0-6).
​"

 

I am a total noob when it comes to this... could you share an example?​ 
 
Cheers,
Rick
 
 ------------------------------

Message: 2
Date: Thu, 2 Jun 2016 19:38:51 +0200
From: "Christof Ressi" <christof.re...@gmx.at>
To: "Rick Snow" <ricks...@gmail.com[ricks...@gmail.com]>
Cc: "pd-list@lists.iem.at[pd-list@lists.iem.at]" 
<pd-list@lists.iem.at[pd-list@lists.iem.at]>
Subject: Re: [PD] Pduino sysex vs. OSC advice
Message-ID:
        
<trinity-add7278d-1946-4da0-b7d2-6db454348f09-1464889131559@3capp-gmx-bs34>

Content-Type: text/plain; charset=UTF-8

>> am able to get the LED to light up using ArduinoTestOSC.pd.

But you can also receive the data from the analog pin, right? (random values, 
if nothing is connected to the pin)

>> "Packet size (#) not a multiple of 4: dropping packet"

I can vaguely remember this message.  Does it happen all the time or just at 
the beginning? Does it happen if you close and open the serial device? It 
didn't cause any problem with me. Actually, the Processing version of 
ArduinoSLIPSerialToUDP has protection against sending unvalid OSC messages.
 

Gesendet: Donnerstag, 02. Juni 2016 um 18:00 Uhr
Von: "Rick Snow" <ricks...@gmail.com[ricks...@gmail.com]>
An: "Christof Ressi" <christof.re...@gmx.at[christof.re...@gmx.at]>
Cc: "pd-list@lists.iem.at[pd-list@lists.iem.at]" 
<pd-list@lists.iem.at[pd-list@lists.iem.at]>
Betreff: Re: Re: [PD] Pduino sysex vs. OSC advice

Thanks Christof (and Martin) for pointing me to the CNMAT library.
 
I did spend a bit of time with this library before posting to the list but the 
tutorial I looked at originally required the ethernet shield. Now I am giving 
the  slipenc/slipdec + OSC functionality a try.  The raw SLIP packages look 
promising as well though I unfamiliar with bitshifting at this point! 
 
Christof, 
Your Arduino_Serial patches look very promising.  Thanks for taking the time to 
make this and send my way!  I've taken a look and after getting the mrpeach 
objects loaded correctly (and the object/message connections correctly 
reconnected) am able to get the LED to light up using ArduinoTestOSC.pd.
 
There are a lot of unpackOSC messages telling me things like "Packet size (#) 
not a multiple of 4: dropping packet" but I think this is not a big problem 
right?
 
Thanks again!
Rick
 
 
 
On Wed, Jun 1, 2016 at 6:40 PM, Christof Ressi 
<christof.re...@gmx.at[christof.re...@gmx.at]> wrote:The CNMAT OSC library 
works well and I often used it with a serial connection. The documentation, 
however, is not so good and some of the examples are buggy. I attached some 
test sketches/patches I once made for a class presentation. The arduino sketch 
explains how to easily send and receive OSC messages via a serial connection 
(make sure you use the same baud rate on both sides!)

Although OSC is convenient, it can be a waste of ressources if you send lots of 
messages. I often work with raw SLIP packages instead, where the first byte is 
used for addressing and the other bytes are the actual data (using some bit 
shifting to break up integers into several bytes). In the arduino code, use 
SLIPSerial.read() to fill an array (instead of an OSC message) and interpret 
your data as needed.

You can also make your own simple protocol where you define a certain character 
to signify the start or end of a message. But how do you know if it's not part 
of the data? SLIP uses escape sequences to handle this case. Two alternative 
solutions:
a) work with fixed length messages and count bytes (not very safe)
b) reduce the range of possible values for your data (e.g. 0-127, like MIDI) 
and reserve the rest for addressing (128-255). If you need a greater resolution 
for your values, just break them up into several bytes. This way, sending a 
single 16 bit integer would take 4 bytes (address, bit 14-15, bit 13-7, bit 
0-6).

Christof

Gesendet: Mittwoch, 01. Juni 2016 um 17:16 Uhr
Von: "Martin Peach" 
<chakekat...@gmail.com[chakekat...@gmail.com][chakekat...@gmail.com[chakekat...@gmail.com]]>
An: 
"pd-list@lists.iem.at[pd-list@lists.iem.at][pd-list@lists.iem.at[pd-list@lists.iem.at]]"
 
<pd-list@lists.iem.at[pd-list@lists.iem.at][pd-list@lists.iem.at[pd-list@lists.iem.at]]>
Betreff: Re: [PD] Pduino sysex vs. OSC advice

There's an OSC library for Arduino here:
https://github.com/CNMAT/OSCUsing[https://github.com/CNMAT/OSCUsing][https://github.com/CNMAT/OSCUsing%5Bhttps://github.com/CNMAT/OSCUsing%5D]
 SLIP it can communicate over serial line using [comport] on the Pd end.
 Martin

 
On Wed, Jun 1, 2016 at 10:29 AM, Rick Snow 
<ricks...@gmail.com[ricks...@gmail.com][ricks...@gmail.com[ricks...@gmail.com]][ricks...@gmail.com[ricks...@gmail.com][ricks...@gmail.com[ricks...@gmail.com]]]>
 wrote:

Hello list!
 
I am looking for some advice on sending messages from PD to an Arduino sketch.  
Essentially, I plan to connect a mac to an Arduino via USB and control a large 
amount of variables within the Arduino sketch from PD.  
 
Is using the sysex message with the [arduino] object message the way to go with 
this?  How can I "tag" the messages so that they go to the correct variable in 
the arduino sketch?  Is there a practical limit to the speed of such a system?
 
I am much more familiar with using OSC messaging between applications but when 
I looked into using OSC with Arduino it seemed like I needed to use an ethernet 
shield (instead of connect via usb) and I would rather not go that route unless 
absolutely necessary.
 
Any advice is much appreciated!
 
cheers,
Rick _______________________________________________


 

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