Running neopixels on mini5 sbc

carcamerarig

Hey guys,
Just reading the dozuki for running neopixelsfrom the mini 5,
https://duet3d.dozuki.com/Wiki/Neopixel_and_DotStar_LEDs

it states max 60 pixels in a strip, is that powered off the board 60 max or can it be more with an external PSU?
I have 178 neo pixels I want to use with an external 5v 10a psu, and utilise the data only off the mini, is it going to be possible? If not can I get a data stream between the mini and sbc and run them off a library on the Pi?

Cheers J

jay_s_uk

thats 60 the can be addressed.
i wouldn't try powering all 60 off the board

carcamerarig

@jay_s_uk said in Running neopixels on mini5 sbc:

thats 60 the can be addressed.
i wouldn't try powering all 60 off the board

Anyway to increase this, need to find a solution for 178.

jay_s_uk

@carcamerarig not without making changes to the firmware.
maybe one for the firmware wishlist @Phaedrux

carcamerarig

@jay_s_uk said in Running neopixels on mini5 sbc:

@carcamerarig not without making changes to the firmware.
maybe one for the firmware wishlist @Phaedrux

@Phaedrux any chance of getting this implemented please?

carcamerarig

@dc42
Could you give me some direction on what i would need to do to hook up 178 Neopixels to the mini 5 please?

jay_s_uk

@carcamerarig well as the limit is current 60, and i doubt it will be increased to 178, you'll have to look at controlling the neopixels with the pi directly.
of course the next question will be how do you get the commands from one to the other?
there are a couple of API's available and you may be able to use execonmcode to run some custom code on the pi.

carcamerarig

@jay_s_uk said in Running neopixels on mini5 sbc:

@carcamerarig well as the limit is current 60, and i doubt it will be increased to 178, you'll have to look at controlling the neopixels with the pi directly.
of course the next question will be how do you get the commands from one to the other?
there are a couple of API's available and you may be able to use execonmcode to run some custom code on the pi.

Right ok thanks, just for clarity what is defining the limit, memory allocation?
for now if just use the 60/178 addressable I could choose the 60 i want right? and as long as its the 60 im good? So im thinking I could use 25 each on the Z frames and 10 on the top cross bar for white illumination and then a 60 pixel random pattern of illumination for status lights. That'd work for now I guess until I read up on the API's you suggested.
What do you think @jay_s_uk?

carcamerarig

@jay_s_uk said in Running neopixels on mini5 sbc:

@carcamerarig well as the limit is current 60, and i doubt it will be increased to 178, you'll have to look at controlling the neopixels with the pi directly.
of course the next question will be how do you get the commands from one to the other?
there are a couple of API's available and you may be able to use execonmcode to run some custom code on the pi.

Who could possibly help me with this execonmcode then?

Phaedrux

You mean this?

https://forum.duet3d.com/topic/13194/dsf-extension-exec-on-mcode-was-shutdown-sbc?_=1615844148559

carcamerarig

@Phaedrux said in Running neopixels on mini5 sbc:

You mean this?

https://forum.duet3d.com/topic/13194/dsf-extension-exec-on-mcode-was-shutdown-sbc?_=1615844148559

Hiya well yes but either method really.
execonmcode for sending printer states for neopixel to the Pi, pretty sure I can install it on the sbc ok but what i'd have to do afterwards would be a mystery to me, ill need to get or make a library on the Pi I know that much.
I put 32 pixels on the neo port on the mini earlier but struggled as M150 is bugged in 3.3b2 (@jay_s_uk pointed it out)

dc42

The issue is that with Neopixels, you need to send the data to the whole string on one go. Additionally, to avoid tying up the processor for the whole time taken to send the data, the data has to be stored in a buffer so that it can be send by DMA. Each Neopixel in the string needs 24 bits of data, and each bit of data takes up 4 bits of data in the DMA buffer. So 1 Neopixel = 12 bytes of data. I chose to support a string of 60 because that's a full Neopixel ring, and 60 * 12 = 720 bytes of DMA buffer is already quite a lot of memory to use up for this purpose

You could drive multiple strings of up to 60 Neopixels each with the data inputs connected in parallel.

dc42

@carcamerarig said in Running neopixels on mini5 sbc:

I put 32 pixels on the neo port on the mini earlier but struggled as M150 is bugged in 3.3b2 (@jay_s_uk pointed it out)

M150 should work correctly with Neopixels in 3.3b2 if you leave out the X parameter. It won't work with DotStar LEDs, which are only supported on Duet 3.

carcamerarig

@dc42 Could you add support for the (RGBW) W component to the FW and increase the DMA buffer to 864 bytes please?

Assuming the missing W component is causing this issue:
M150 R255 P64 S10
https://drive.google.com/file/d/1j5PdbD0kTev6zpldqQvOruVhVltT3sxH/view?usp=sharing

dc42

@carcamerarig said in Running neopixels on mini5 sbc:

@dc42 Could you add support for the (RGBW) W component to the FW and increase the DMA buffer to 864 bytes please?

Assuming the missing W component is causing this issue:
M150 R255 P64 S10
https://drive.google.com/file/d/1j5PdbD0kTev6zpldqQvOruVhVltT3sxH/view?usp=sharing

Already on the firmware wishlist.

carcamerarig

@dc42 said in Running neopixels on mini5 sbc:

@carcamerarig said in Running neopixels on mini5 sbc:

@dc42 Could you add support for the (RGBW) W component to the FW and increase the DMA buffer to 864 bytes please?

Assuming the missing W component is causing this issue:
M150 R255 P64 S10
https://drive.google.com/file/d/1j5PdbD0kTev6zpldqQvOruVhVltT3sxH/view?usp=sharing

Already on the firmware wishlist.

Excellent, do you think it'll make 3.3? looks like its been on the to do list for a while.

dc42

RGBW Neopixels are now supported in the 3.3 source code, so release 3.3beta3 will support them.

carcamerarig

@dc42 said in Running neopixels on mini5 sbc:

RGBW Neopixels are now supported in the 3.3 source code, so release 3.3beta3 will support them.

@dc42 That’s great thanks, is increasing the DMA buffer size to 864 bytes likely to happen in 3.3?