Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Problem with recently Purchased WS2812B Products using the Teensy 3.2 and the Teensy 4.0 MCUs with FastLED #944

Open
chemdoc77 opened this issue Dec 27, 2019 · 1 comment

Comments

@chemdoc77
Copy link

@chemdoc77 chemdoc77 commented Dec 27, 2019

I recently received an order from Ray Wu’s Store. I tested the following products:

  • WS2812B 16*16pixels led digital flexible panel light
  • 4m 60LEDs/m DC5V addressable WS2812B led pixel strip
  • 1m 144LEDs/m DC5V addressable WS2812B led pixel strip

In testing these products with my FastLED test sketch (which was slightly modified for the number of pixels and using the WS2812B chipset):

https://gist.github.com/chemdoc77/52ded62fc801247cc648b1eb84f9d2ca

I have found that they work as expected with the Arduino Nano, Wemos D1 mini Pro and the Lolin D32 MCUs. They do not work correctly with the Teensy 3.2 MCU at CPU speed of 96 MHz but do work correctly when I lower the Teensy 3.2 CPU to CPU speed of 48 MHZ.

For the strips, the cd77_colorwipe_dot function did not work properly (five or more pixel lite up at a time, not only one pixel at a time as it should) but the fill_solid function did work correctly at the 96 MHz CPU speed. For the 16*16 panel, it did not work correctly at all for the fill_solid function or for the cd77_colorwipe_dot function at the 96 Mhz CPU speed.

All of the products do not work correctly at all with the Teensy 4.0 MCU at any CPU speed using my new product test sketch for the Teensy 4.0 MCU:

https://gist.github.com/chemdoc77/8b50f86d3bef8e777ccca62759efbd2f

My prior WS2812B strips and panel that I purchased from Ray Wu’s Store in 2018 work correctly with the Teensy 3.2 at 96 MHz, with the Teensy 4 and with the other aforementioned MCUs.
When I contacted Ray Wu about this, Ray Wu sent me an email stating:

“the WS2812B has been upgraded to the V5 version this year, so it is a little different than before.”

Has anyone else experienced this type of problem with recently purchased WS2812B products?

Does anyone have any suggestions on how to make these products work at the higher CPU speed for the Teensy 3.2 and to work for the Teensy 4.0?

Here are the pictures of the three products:

Use the zoom feature at the bottom in google pictures to get a closer look.

Here are the links to the three products that were just purchased from Ray Wu’s Store:

1M long 144leds/m WS2812B(5050 rgb led with WS2811 IC built-in) led pixel strip,DC5V,waterproof in silicon tube;BLACK PCB:

https://www.aliexpress.com/item/2047880507.html?spm=2114.12010615.8148356.5.98085aa9zhZEy1

4m 60LEDs/m DC5V addressable WS2812B led pixel strip,waterproof in silicon tube,60pcs WS2812B/M with 60pixels;BLACK PCB:

https://www.aliexpress.com/item/948302882.html?spm=2114.12010615.8148356.70.755656e0okcfsl

P10mm WS2812B 1616pixels led digital flexible panel light,size:17cm17cm,DC5V input:

https://www.aliexpress.com/item/2038897589.html?spm=2114.12010615.8148356.3.397d25eetxU2yI

Also. I just tested the 4 meter - 60LEDs/m strip with the Teensy 3.2 at 48MHz and:

It does work with no level shifter and a 3 ft length of 18 gauge cable with JST connectors between the Teensy and the strip.

It does not work at all with no level shifter and a 15 ft length of 18 gauge cable with JST connectors between the Teensy and the strip.

It does work with level shifter and a 15 ft length of 18 gauge cable with JST connectors between the Teensy and the strip.

I am using the following two resistor protection circuit between the Teensy 3.2 and the LEDS as seen in:

https://forums.adafruit.com/download/file.php?id=13633&sid=6aff0fe6d53a963e8920def6d868e0d7

I am assuming that without the level shifter and the longer cable, the “D in” voltage drop to the LED is such that the strip did not work. While with the level shifter and the longer cable there is a “D in” voltage drop but the “D in” voltage at the chip is still high enough due to the level shifter so that the strip did work. I will continue using the level shifter for insurance.

@MartyMacGyver

This comment has been minimized.

Copy link

@MartyMacGyver MartyMacGyver commented Dec 27, 2019

The chip inside looks pretty tiny... the actual WS2812B-V5 should look like this, per WorldSemi's own listings on Alibaba looks different (edit: but perhaps their photo is just of an older model... getting more info before I commit to that determination)

I'd expect that chonkier chip as they integrated the filter cap into there as well... (maybe not?) additionally, new PCBs for this shouldn't even need external filter caps (see the intro for the V5 devices)... eliminating them allows better power rails too, so it's a win-win. Maybe Ray had old stock to use up?

Also, the fact that this works at all for you is telling: you really ought to be having bad timing issues with a V5 based on the new specs. The apparent need for level shifting despite the redesigned input block on the V5 is also odd to me.

Based on all that, I really wonder if what you have are V5 devices at all.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Projects
None yet
2 participants
You can’t perform that action at this time.