Ambient Lighting - Upgraded from UNO R3 to Teensy 4 and there are lots of issues.

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OGShua

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Background:

- This is for work.
- I am using a custom three display Processing (v2.2.1) sketch on a Win 10 machine that connected to my UNO R3 via USB running 'LEDstream_FastLED' on the UNO.
-When I inherited this program we were using [Adalight 36mm square digital RGB LEDs](https://www.adafruit.com/product/683)
-I switched us to 5v 30 LED/m WS2812b (GRB), everything works wonderfully.
-We are looking to move production of this solution in-house and as I need to teach others how to build the controller, it seemed smarter to move to the Teensy 4 as it is not only more powerful, it would only require soldering three wires as opposed to all of the pins on the ProtoShield and the three connector wires.

Where I stand presently:

- I have three Teensy 4s each with the data wire hooked up to a different pin. 11, 14, 15 due trying to get the pin to line up with the UNO (UNO Pin11 SPI Master our - T4 Pin 14)
- When I run lighting tests, the color reproduction is spot on.
- When I launch processing color is WAY off. A Red square will show Greenish-blue, if I switch the color from GRB to RGB Red shows as Pink.
- With the UNO when the program launches all of the LEDs turn off until they are reproducing color. The Teensy goes pure white. With Red showing as Pink I am wondering of there is a command that is reversed, Red shows Green, Black is White....


UNO R3

Teensy 4


I can post code if needed, however, I was hoping that there might be some other suggestions I could try first as I really want to do the leg work on this to improve my knowledge and troubleshooting skills.

Thank you all in advance!
 
Note, the Teensy 4 only has pin 11 being SPI MOSI, pin 12 being SPI MISO, and pin 13 being SPI SCLK. In particular, pin 14 is not the SPI MOSI pin. On the Teensy 3.x, pin 14 was an alternate for SPI SCLK (normally pin 13), but the Teensy 4 does not support this.

Given you are going from a UNO to a Teensy, you may have voltage issues. The Teensy only runs at 3.3v while the UNO runs at 5v. Some devices that are 5v will not always recognize 3.3v signals. Depending on who made the WS2812B strands, there are so-called grumpy LED strips that just will not work if you don't shift the voltage. However, since WS2812B has fixed timing cycles, you would need to use a voltage level shifter that is fast enough. The 74AHCT125 tends to be the go-to device for doing the level shifting.
 
Saying that I am still testing with Pin 11, that shouldn't that cause the error in color reproduction, correct?

If so, I may very well need to smack myself for my mistake.

I use two 5v 10a PSUs to power the lights, so I am not sure if voltage would be an issue. Also, I am tied into the 5v pin on the Teensy.
 
Also, if the LEDs are lighting without issue when running the Example "Teensy 4" -> Adafruit NeoPixel -> strandtest would I still need to be worried about voltage?
 
Good morning. I received my 74HCT125 and wired it up based on what others who are using a T4 and NeoPixels . I can no longer get anything to display, even the standard StrandTest.

I am running

T4 Pin11 to 1A
1Y to NeoPixel Din

Power Ground to Ground and 1OE
Power 5v to VCC


Help please.

T4 and Level.jpg

Level.jpg
 
1) It does not work to just plug the pins into the teensy.
They give no - or very bad - contact.

You need to solder them.

I see no solder on 3 (or is it 5?) Volt +

If hope not both, USB AND external 5V are connected?

2) Output-enable is not connected.
Edit: Oh no, sorry, did not see the black wire.
 
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I soldered the pins I was using, GND and pin 11. The 5v was not soldered as I had read that I did not need it because I am using an external 5v source. I forgot to pull the lead before the photo. I'll solder the 5v just in case I need it.
 
That's right. You should disconnect it. If the voltage comes from external.
Are the wires OK? I had more than once problems with faulty, cheap china wires..

If you have a DVM you can test if the pins on the 74 have the correct voltages.

You can also write a short "Blink" program that should "Blink" on PIN11 - then you can measure the output on the 74x if it works.

If the hardware is OK, and verifired that it works then, it might be a softwareproblem.
 
What do you think would cause it? (Before I added the Level Shifter, the T4 would run without being plugged into USB, now it HAS to be plugged in)

Also, not that I think it would matter, however, it is a Dell.
 
Ok, Dell ;)

It is more likely a loose contact somewhere else.
Remove the cable to Teensy 5v if you're using a PSU.
 
Can you measure the voltage there? (Without your wire connected)
Take a look at the Teensy schematic. Vin (on the board it's called "5V") is directly connected to USB. So you connect the PSU with your Dell, if you use that wire..


I don't know what the problem is.. it should work :)
 
Can you measure the voltage there? (Without your wire connected)
Take a look at the Teensy schematic. Vin (on the board it's called "5V") is directly connected to USB. So you connect the PSU with your Dell, if you use that wire..


I don't know what the problem is.. it should work :)

My digital meter is at home, however, with the analog one at the office, both the DC jack, and the 5v VIN so ~5v (wire from DC to Teensy disconnected)

DC Jack.jpg

5v VIN.jpg

EDIT: The ground plugged into the Hot row was moved back to the Ground. The Hot row on that side was never energized so there was no chance of damaging the board.
 
I have another Teensy. I'll wire it up this week and test...maybe I messed up this board somehow....

Thank you for all of your input, honestly.
 
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