Configuring SK 6812RGBW LED while 12864mini is connected

Sn1kk3r5

Hi there,

I require help, please.

My 12864 mini is working fine with config:

M918 P2 R6 C30 E4 F2000000 			  		   ; connect a display directly C= Contrast
 
M150 X2 R0 U0 B255 P200 S1 F1 			  	   ; display led R= Green U= Red B= Blue
M150 X2 R0 U255 B0 P200 S1 F1 			   	   ; left encoder led
M150 X2 R0 U0 B255 P200 S1 F1

So I connected my LED stripe to the NP_LED connector and added the following to my config:

M150 X4 
M150 X4 R255 U0 B0 W0 P100 S1 F1
M150 X4 R0 U255 B0 W0 P100 S1 F1
M150 X4 R0 U0 B255 W0 P100 S1 F1
M150 X4 R0 U0 B0 W255 P100 S1 F0

I did replace

M150 X2 R0 U0 B255 P200 S1 F1

with

M150 X2 R0 U0 B255 P200 S1 F0

on the display config.

I as well disabled the display with comments to try some kind of stand alone. Nothing I tried worked so far...
It's always changing the colors of my display and the stripe won't even turn on, no matter if the display is configured or not.

I'm running:
DWC 3.4.0-b6
Board: Duet 3 Mini 5+ (Mini5plus)
Firmware: RepRapFirmware for Duet 3 Mini 5+ 3.4.0beta6 (2021-11-06)
Duet WiFi Server Version: 1.26

Any advice is highly appreciated.

Thanks in advance.

Cheers
Cris

Gixxerfast

I'm not quite sure I understand the problem but have you read this:

"On the Duet 3 Mini, X1 selects the NeoPixel output on the main board, and X2 addresses the RGB LEDs on some 12864 displays."

From here https://duet3d.dozuki.com/Wiki/M150

o_lampe

@sn1kk3r5
You might have to raise the 'S' parameter to 2 or more. The first LED might always be the display LED, then comes the strip.
It's also possible, you'll need a levelshifter to 5V and adjust the frequency (Q-param) to a value the SK6812 works with.
Common WS2812B NeoPixels work with 800kHz, not sure about yours.

Sn1kk3r5

@gixxerfast said in Configuring SK 6812RGBW LED while 12864mini is connected:

I'm not quite sure I understand the problem but have you read this:
"On the Duet 3 Mini, X1 selects the NeoPixel output on the main board, and X2 addresses the RGB LEDs on some 12864 displays."
From here https://duet3d.dozuki.com/Wiki/M150

Yes I did read it, and tried it as well with no success.

The Problem is, no matter what I try to configure for the LED strip, it changes my display but the strip remains dark.

@o_lampe said in Configuring SK 6812RGBW LED while 12864mini is connected:

@sn1kk3r5
You might have to raise the 'S' parameter to 2 or more. The first LED might always be the display LED, then comes the strip.
It's also possible, you'll need a levelshifter to 5V and adjust the frequency (Q-param) to a value the SK6812 works with.
Common WS2812B NeoPixels work with 800kHz, not sure about yours.

I tried S2 with no success as well.
Havent played around with the Frequency yet, will give it a shot now. Thanks for the hint.
Maybe I need a travelshifter, not sure about that, but what I understood so far is the NP_LED connector is rated for up to 1A... so 4 LED's and the display wouldn't do much here.

What makes me wonder is the fact that some commands after the display config are reaching the display.... as my normal display config sets the display to blue and red.... after running the strip config, my display is all green.

Gixxerfast

Here's a stupid question, but ... you are supplying external 5v to the power the neopixels?

o_lampe

@gixxerfast said in Configuring SK 6812RGBW LED while 12864mini is connected:

Here's a stupid question, but ... you are supplying external 5v to the power the neopixels?

@Sn1kk3r5
He's right, I just studied the schematics and the good news is, that there IS a 5V levelshifter for NP_out, but you need external 5V supply.
There's also a jumper for ext. 5V or SBC, not sure if you can jumper it in a way to use the internal 5V regulator?

Sn1kk3r5

@o_lampe said in Configuring SK 6812RGBW LED while 12864mini is connected:

@gixxerfast said in Configuring SK 6812RGBW LED while 12864mini is connected:

Here's a stupid question, but ... you are supplying external 5v to the power the neopixels?

@Sn1kk3r5
He's right, I just studied the schematics and the good news is, that there IS a 5V levelshifter for NP_out, but you need external 5V supply.
There's also a jumper for ext. 5V or SBC, not sure if you can jumper it in a way to use the internal 5V regulator?

No I don't as I thought this won't be needed as longs as I stay under 1A limit.

TBH I don't see the reason why NP_LED holds a 5V and GND when a external PSU is needed anyway. Who will connect a external 5V PSU to the mini when the mini then limits the NP_LED to 1A.

Gixxerfast

@sn1kk3r5 said in Configuring SK 6812RGBW LED while 12864mini is connected:

TBH I don't see the reason why NP_LED holds a 5V and GND when a external PSU is needed anyway. Who will connect a external 5V PSU to the mini when the mini then limits the NP_LED to 1A.

But I don't think the mini5+ will limit anything. Please correct me if I'm wrong but the external 5v ends at the 5v_select jumper. Then if you disable internal 5v and only run external 5v I don't know what happens regarding that but I don't see what would be limiting except traces and connectors

o_lampe

@sn1kk3r5
For 4 LEDs you could use internal 5V from an empty connector. Just have to wire the strip to it and only use GND + NP_out from the NP-header.

Sn1kk3r5

@gixxerfast

Yeah probably I do misunderstand the guide in this matter. Never the less a 5V PSU is on it's way, I'll report tomorrow or the day after.

Sn1kk3r5

@o_lampe

MY example was just to start the configuration on a working example rather then just start writing a macro.

So from what I understand from your and Gixxer's answers
is, the 5V will get passed from 5V_EXT to the NEOPIXEL connector. The only limit then is coming from the PSU itself, right?

Gixxerfast

@sn1kk3r5 max. 60 LEDs though according to the docs.

Sn1kk3r5

@gixxerfast

Guideline stated begining from FW 3.3 it's 80, but this would fit no matter if 60 or 80

dc42

@sn1kk3r5 said in Configuring SK 6812RGBW LED while 12864mini is connected:

Hi there,

I require help, please.

My 12864 mini is working fine with config:

M918 P2 R6 C30 E4 F2000000 			  		   ; connect a display directly C= Contrast
 
M150 X2 R0 U0 B255 P200 S1 F1 			  	   ; display led R= Green U= Red B= Blue
M150 X2 R0 U255 B0 P200 S1 F1 			   	   ; left encoder led
M150 X2 R0 U0 B255 P200 S1 F1

So I connected my LED stripe to the NP_LED connector and added the following to my config:

M150 X4 
M150 X4 R255 U0 B0 W0 P100 S1 F1
M150 X4 R0 U255 B0 W0 P100 S1 F1
M150 X4 R0 U0 B255 W0 P100 S1 F1
M150 X4 R0 U0 B0 W255 P100 S1 F0

...

I as well disabled the display with comments to try some kind of stand alone. Nothing I tried worked so far...
It's always changing the colors of my display and the stripe won't even turn on, no matter if the display is configured or not.

That's as expected:

X1 = RGB Neopixels connected to NP_OUT
X2 = RGB Neopixels connected via the display
X3 = RGBW Neopixels connected to NP_OUT
X4 = RGBW Neopixels connected via the display

So X2 and X4 both address the display.

Sn1kk3r5

@dc42

Thanks for the reply.

I changed my config to X3 but this doesn't changed anything...
Is it because of missing 5v on 5v_EXT? Or should the work even without 5v_EXT until a limit of 1A?

Cheers and Thanks!

o_lampe

@sn1kk3r5 said in Configuring SK 6812RGBW LED while 12864mini is connected:

stated begining from FW 3.3 it's 80, but this would fit no matter if 60 or 80

It's 60 RGBW or 80 RGB LEDs, but at eg. 50% brightness it can be doubled.
I'm currently playing with Arduinos fastLED library, which has amazing features. There you can set max. Watt limit for all strips connected and the brightness of each LED is controlled automatically. Very handy for animated strips or matrix's

Currently I'm working out how to control the LEDs on the Arduino from Duet or Slicer-generated gcode

Sn1kk3r5

@o_lampe

That's by far more then I need. But thanks for the information.

Currently I'm trying to get used to the coding, which seems to have some strange effects....

Just to ensure I understood yesterdays conversation right.

I now have an external 5V 18A 90W PSU. Can I connect this one to the mini 5+ and power about 60 LED'S from the NEOPIXEL connector

or do I have to connect the LED'S to the PSU directly cause of the power drain?

Thanks in advance.

Cheers
Cris

o_lampe

@sn1kk3r5 said in Configuring SK 6812RGBW LED while 12864mini is connected:

do I have to connect the LED'S to the PSU directly cause of the power drain?

That's what I would do. Just connect the Duet over GND and Data-in to the strip.

Sn1kk3r5

@o_lampe
Sure that's what I will do in case it'S the only possibility.

But to have a nicer cable management it would be good to have one pair from the PSU to the mini and one from the mini going to the strip