Teensy APA102 POV Poi / Pixel Poi Build. Tutorial

Hi guys,
I got a new score on refreshing rate.

crazy.jpg
this doge.bmp is a 24bit bmp with a width of 80 pixel and gets a horrible 3900 FPS, that squeezes the image
okay, when it goes to DMASPI it turns out that FPS depends highly on micro-SD cards, but not by size (as this one uses a 128Mbyte card, could be pretty old)

I'm still finding if there is something deciding.

other finding:
when using apa102 chain over 80pixels, dont go over 12Mhz or the pixels chained faraway (>~80) goes crazy,
my crazy leds happen on 16Mhz, by 144 LEDS only the far LEDS goes wild, but same script and hardware fine at 12Mhz.
 
Hiya.
I recently built a pair of these poi which turned out great :) here's some pictures

View attachment 13106 View attachment 13107 View attachment 13108

I have also rewritten the code generation webpage to create a demo of what the poi will look like allong with some ways to change certain things like the number of LEDs being used. I can upload my version of the webpage somewhere if there's enough interest bit it'll take a while as it's quite a bit of work to pull it out of my personal website.
View attachment 13105

I'm interested in porting the code to the ESP platform and will be happy to assist anyone else wanting to do the same.
Also I was wondering what the lowest clock speed can be used and still generate the same effect, as the teensy 3.2 is quite expensive so i'd like to look at alternative controllers?
Cheers

Hi I would love to see your website. Can I see it please?
 
@banya1987. I don't have any files for InvisiBug's project. Perhaps try a GitHub search or contacting the user via PM.
 
Hey guys!!

I will make stuff for spining with two stripes of 72 leds on each side. (0,5m) the pictures will be 72 pixels high.

I was unlucky and discovered this forum too late. I was not aware of teensy 3,6 existence :(.. so just today my teensy 3,2 came to me.

How many simple images i can store on teensy 3.2? 256K flash. I would not like to buy teensy 3.6 if it is not necesary. I already bought Protrinket form adafruit and then i saw that Teensy is far better and i bought teensy 3.2, now i see that teensy 3.6 is better :) LOL i have many parts but nothing working.

Thanks InvisiBug for converting tool :) lifesaver to me.
 
there is some discussion on how many images users have been able to store. go to message #62 and #63 in this thread.
 
there is some discussion on how many images users have been able to store. go to message #62 and #63 in this thread.

Thank you for fast response!

4 images 72*72 on teensy 3.2 :(

ordering teensy 3.6 :)

i will put theese non used boards to use or make a donation to highschool electronic group :)
 
This might be a bit of a ramble, sorry in advance.

So I first heard about this kind of poi through a company called "Light Toys". They have a very professional version of what we have been making in this thread.
They've made some really great software to use with their "Visual Poi" which just so happens to include a load of demo images (Which have been specifically made to work really well with their poi).

I mostly use these images when I'm spinning.

Bit of a side note but I actually emailed the lead designer of the "Visual Poi" asking for some help. I sent him some long exposure pictures of me spinning for feedback and my poi were using his own images, oops. He was actually super cool about it and gave me a bunch of useful information.
If you use the same images in your poi as I do you should be able to fit about 10 in one go.
I'm actually working on a form of compression (Run Length Encoding) at the moment and nearly have it working. I'm fairly sure the Teensy 3.2 will be able to fit 30 images or more.

I personally don't think a teensy 3.6 is worth the upgrade. I never find myself wanting more than a few images making the extra space of the 3.6 unnecessary.
I've recently added a bunch of other functions using a single button to cycle through them (I'm currently working on a write up).

Hope this helps (Sorry for the rambling)
 
i first saw this visual poi on OZORA psytrance festival 2 years ago. And i was woow i need to have this. Im also learning kungfu for 7 years and can spin the staff quite good.

Thank you for the imput. Do you maby have somwhere those images for download?

I already ordered teensy 3.6. It was 35 eur with shipping from germany. The whole cost of staff will be around ~200 eur. Quite expensive but i want to have good staff.

I will instal 8.5 A of lion batterys. ( 2x https://www.nkon.nl/rechargeable/21700-20700-size/sanyo-ncr20700b-lithium-battery.html)

For powering teensy i will use step up regulator to 5v.

I will also install small lcd voltmeter so that you can alwas see how much juice is in battery.

I want to use this code with remote. https://learn.adafruit.com/supernova-poi/code-1 I hope this also works on 3.6. My programing skils are low. I know what to look to modify the existing code but to write something new is big NO NO :).
 
Hey guys!!

I will make stuff for spining with two stripes of 72 leds on each side. (0,5m) the pictures will be 72 pixels high.

I was unlucky and discovered this forum too late. I was not aware of teensy 3,6 existence :(.. so just today my teensy 3,2 came to me.

How many simple images i can store on teensy 3.2? 256K flash. I would not like to buy teensy 3.6 if it is not necesary. I already bought Protrinket form adafruit and then i saw that Teensy is far better and i bought teensy 3.2, now i see that teensy 3.6 is better :) LOL i have many parts but nothing working.

Thanks InvisiBug for converting tool :) lifesaver to me.
Teensy 3.2
I using Output Height(number of leds on Poi) 72
5x Output width(number of image slices) 150
and have space for one more of 100 slice

5x150 slice and one for 100 slice if i need
good luck
 
Teensy 3.2
I using Output Height(number of leds on Poi) 72
5x Output width(number of image slices) 150
and have space for one more of 100 slice

5x150 slice and one for 100 slice if i need
good luck

Thank you guys for your help. Im designing parts for my stuff. When assambeled and testet i will upload the 3d files so that everyone can use them :).

I have one important question... do i need access to Teensy 3.6 button? as i reed it is neaded to push it after uploading the code. :(((( i hope there is some other way so that i can make teensy non removable.


3.png


2.png
 
@masterslav

if your program is not needed to upload for your user, you don't need to leave the button reachable

otherwise,
you can line the program pin from the board out to ground through some other push button /location, so it's easier to access
 
@masterslave

wow, there are so many new pixel shops today :\
guess thanks to widely available pixel strips, and the maker culture.

not yet,:p:p I'm investing on my low-power radio pairing model with nrf radio, in fact just coding right now.

I consider motion sensor a less needed feature in POV performance.
Your pictures, moves and speed should be pre-defined, and heavy practiced so you don't make mistakes.
so your speed should not include big ranges, no need to worry about stretch.

also POV effects actually work fine in a range of speed :cool::cool:

with a gyro it is probably very easy to achieve image stablizer with little codes.
https://www.youtube.com/watch?v=XcuS0mnEDPw

stretch stablizer needs more computing and probably DMA with SPI/I2C to catch up data in time without disturbing your image.
 
@masterslave

wow, there are so many new pixel shops today :\
guess thanks to widely available pixel strips, and the maker culture.

also POV effects actually work fine in a range of speed :cool::cool:

with a gyro it is probably very easy to achieve image stablizer with little codes.

I found them after half year of searching 😀.. not so easy to find even if you know what you are searching. But they have affordable and cool looking products. Except battery packs are so weak.. best models have around 2.4 ah.. My shaft will have 8.4 ah. I like to go to psytrance events and spin for whole night 🤣. Also i will have 288 leds.. 15A peak consumption at peak brightness.. but i know it is not good to use at full bright becouse i go blind 😂🤣

Thank you for calming me down. I cant wait to assamble it this week.. and try how it looks. I also ordered gyro and accelometer chips. 0.99 gbp/pcs for future modifications. Sadly i still have to learn a lot how to implement gyro as image stabilisation.



https://www.ebay.co.uk/itm/1-2-5-10...r-MPU-6050-Raspberry-Pi-Arduino-/153030528330
 
I found them after half year of searching ��.. not so easy to find even if you know what you are searching. But they have affordable and cool looking products. Except battery packs are so weak.. best models have around 2.4 ah.. My shaft will have 8.4 ah. I like to go to psytrance events and spin for whole night ��. Also i will have 288 leds.. 15A peak consumption at peak brightness.. but i know it is not good to use at full bright becouse i go blind ����

if you had extra buttons or time to work on, you can make the brightness adjustable after programmed. I use such settings to swap between daylight and night.

I plan to solder all the possible parts on my own designed PCB, so I had to avoid tricky IC packages :(
QFN or apa102-1515 is by far the hardest I can handle, with paste and hot air/plate.

Really had some tough time with those chips, when you're not sure is if your code's error or hardware's corrupted.

but ofcourse you can have fun playing and prototyping with modules :eek::eek:
 
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Ridiculously n00b question here: Why is it that I seem to need a level shifter driving my POV poi APA102 LEDs with a Teensy 3.6 whereas I don't need one with a Teensy 3.2? Thanks!
 
Ridiculously n00b question here: Why is it that I seem to need a level shifter driving my POV poi APA102 LEDs with a Teensy 3.6 whereas I don't need one with a Teensy 3.2? Thanks!

it is safer and stabler as they work on different voltage by datasheet.

If you don't shift the level, you have to take your own risk that they don't work as intended
By far I didn't meet any level-related error by direct driving apa102 with T3.6 SPI pin signals. ( and they both powered directly by 4.2V Lith
ium battery)
also by solder error you can possible short higher voltage to SPI pins and burn your T3.6, that happened to me once.

-----
another usage: if there is a CS pin on your level-shifter, it is also better when you also use the SPI port for other use.
since apa102 does not have CS, it may flash randomly if you use the same SPI port to use, for example, a SDcard.
it need some 32 bits of "0" for apa102 to take next line, this random flash will not always happen.
 
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What's the best guide to Follow for my first Pixel Poi Build?

Hello folks, just starting to read through this thread, some really great projects, thanks for sharing!

I'm wondering what would everyone recommend as a build guide for a first time Pixel POI build?
The InvisiBug Orbit build guide? Or??
What is the current recommended type of material to use, for attaching the LED strips to? (If I use the APA102 144/LED's /m Strips) where do you purchase?

Thanks for any input! Looking forward to gathering up the supplies and attempting to build a pair of Pixel Poi sticks.
 
Looks like it's difficult to purchase authentic APA102C 5050 144/m strips these days, unless you pay $50 + tax + shipping to Adafruit.
Anyone have a less expensive online source for the legit APA102C 5050 144/m LED strips? Don't want to end up with a under performing counterfeit roll.
How about the SK8922 based strips? Is anyone using these? Will they work okay for this type of POI project?
 
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