Neotrellis issue

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DIYglenn
 
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Re: Neotrellis issue

Post by DIYglenn »

Yes, the grounds are tied together, but not directly between all the cards, 4 and 4 are directly connected, and VIN + GND from each set are terminated outside the cards.

So ground is tied, but we did this to avoid high amounts of current going through the PCB traces.

Our next workaround (although not optimal) would be to separate into rows of 8, each connected to a separate Arduino (or supported compatible). We would probably still separate GND + VIN into at least two sets of 4, as a max draw with all white LEDs is 8A.

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adafruit2
 
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Re: Neotrellis issue

Post by adafruit2 »

grounds must be tied together directly - do not create long ground loops!

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DIYglenn
 
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Re: Neotrellis issue

Post by DIYglenn »

adafruit2 wrote:grounds must be tied together directly - do not create long ground loops!
We do not have any ground loops, that's why we avoided to solder between the rows.

We did this to be absolutely sure that the traces of some NeoTrellis boards won't get all the current.

Are you sure this is the culprit of the problem? The data connections are soldered directly to all boards, and the ground has zero resistance between the outer boards.
I cannot see how this could be an issue?

For +5V and GND we have to connect it multiple places, this to make sure one NeoTrellis board won't get all 23 amps through its traces.

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adafruit2
 
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Re: Neotrellis issue

Post by adafruit2 »

we don't think its the only culprit, only that it doesnt help matters when your ground is shifting around a lot :) we recommend 'breaking' up the boards into chunks of 4, and putting each on an I2C port, seeing if those work well

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chrfriese
 
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Re: Neotrellis issue

Post by chrfriese »

Hallo,

I have a similar issue with frozen system. In my setup I’m using two separate Neotrellis connected to a single Wemos D1 mini (ESP8266). The cables between Neotrellis and Wemos are approximately 1.5m. Wemos is connected to WiFi and communicating with a MQTT broker. After a “correct” code on one of the Neotrellis, it will submit a MQTT message.
I tried two different configurations: a) both NeoTrellis handled as separate entities and b) the Neotrellis handeled as MultiTrellis.
In both cases I end up in the frozen state after a random number of key presses.

Is it possible, that the ESP8266 is too weak for the Neotrellis?
I have 20ms delay between the trellis.read(). Is that too short?
Any idea how I could debug the system to verify which part of the system causes the crash?

Best regards,

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adafruit2
 
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Re: Neotrellis issue

Post by adafruit2 »

chrisfe, just to check, have you tried short wires 1.5m is quite long! i wonder if we're getting i2c command errors. also are you using the busy pin

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chrfriese
 
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Re: Neotrellis issue

Post by chrfriese »

I made a short test before installation and didn't see the error but maybe I just didn't test well enough. Now it's installed and a lot of work to modify. But you're right, I'll re-check with Wemos installed directly at Neotrellis location.

What do you mean with busy pin? The INT pin of Neotrellis? So far I'm only using SDA/SCL/VDD/GND for the connection.

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DIYglenn
 
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Re: Neotrellis issue

Post by DIYglenn »

adafruit2 wrote:we don't think its the only culprit, only that it doesnt help matters when your ground is shifting around a lot :) we recommend 'breaking' up the boards into chunks of 4, and putting each on an I2C port, seeing if those work well
I’m afraid that if I connect all the grounds together, and one of the “main” ground cables to one of the sets of four breaks, the ground will be able to take a different route, and potentially destroy a trace on one of the NeoTrellis boards.

8x NeoTrellis works fine, so we’re considering splitting it up - yes. But would we need 3x Arduinos for this?

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adafruit2
 
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Re: Neotrellis issue

Post by adafruit2 »

glenn, yes you'd use multiple arduinos

the busy pin is marked INT - you can use it so there's less polling - connect it to a gpio and indicate it here
https://github.com/adafruit/Adafruit_Se ... is.cpp#L25
does that help?

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DIYglenn
 
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Re: Neotrellis issue

Post by DIYglenn »

adafruit2 wrote:glenn, yes you'd use multiple arduinos

the busy pin is marked INT - you can use it so there's less polling - connect it to a gpio and indicate it here
https://github.com/adafruit/Adafruit_Se ... is.cpp#L25
does that help?
Thanks, I’ll check it out. We’ll leave the grounds as it is for now, as it should be sufficient. The data signals are connected directly, and ground is only a reference, and everything has common ground.

We also shortened our data wires to make sure there are no issues there (as per the suggestion to chrfriese)

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chrfriese
 
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Re: Neotrellis issue

Post by chrfriese »

As I have a rather small setup, I added to each of my two Neotrellis an individual Wemos with very short wires.
Rather inefficient, but for now it seems to work. The system is not stopping.

I'll try the INT pin to further reduce the load on Wemos in case I see the system stopping.

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airoptix
 
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Re: Neotrellis issue

Post by airoptix »

-
Last edited by airoptix on Wed Jan 23, 2019 12:39 pm, edited 1 time in total.

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adafruit2
 
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Re: Neotrellis issue

Post by adafruit2 »

airo, please start a new thread

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PatMaximum
 
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Re: Neotrellis issue

Post by PatMaximum »

Hi Guys.
I'm considering using 4 or 5 Neotrellis in a Midi controller and am curious if DIYglenn got the 3x8 setup working..
Thanks in advance

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adafruit_support_carter
 
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Re: Neotrellis issue

Post by adafruit_support_carter »

@PatMaximum Please start a new thread for your question.

Closing this thread.

Please follow this issue and add any helpful information there:
https://github.com/adafruit/Adafruit_Seesaw/issues/18

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