Hey Guys! I need some urgent help to hit a deadline on coming monday.

I’ve looked at the slight difference between the 74HC245 and the 74HCT245 (HC vs HCT), and I don’t fully understand it, but I believe it would still work in this use case.
From the data sheet:
For HC the condition is VI = GND to VCC
For HCT the condition is VI = GND to VCC − 1.5V

Would need someone with more electronics experience to explain that.

The ones I bought some time back were these 74HCT245N (with an N on the end. I think the N has to do with what temperature range they’re rated to operate in. But I’m not taking mine to the arctic or burning man. :wink:
http://www.mouser.com/search/ProductDetail.aspx?R=0virtualkey0virtualkeySN74HCT245N

Okay. So how would I set this up altogether?

The level shifter goes between the MCU outputs and your strips inputs, and you run your data/clock signals through it. Lucky you, there are exactly 8 inputs and outputs and you have 4 strips for a total of 8 lines to run through it. :slight_smile:
Another image to show wiring example:

thats indeed lucky :slight_smile: thanks for the help. i will set this up tonight. i will set it up with an arduino, test it and then wire everything to the teensy on the weekend

Hey Guys! Got it running. Well almost. Have a weird flickering issue. Also in other examples… Made a video to show you whats going wrong. https://youtu.be/7ZyS8NtEDN8

Cool. Double check that you have all your grounds connected together.

okay. will do. how does the level shifter work? how do i connect it? just connect with the opposing pins?

Whatever is input on A1 would output on B1. Input on A2 would output to B2, etc.
** Note that paired input and output pins are NOT exactly opposite each other on the chip.

Pin layout for the level shifter 74HCT245

okay. where do i find those layout? have the 74HC245 now. the guy in the store have me a 1uF capacitor. will that work too? or should i get a bigger one?

I found those layouts in my Google drive folder! I tend to make those sort of documents and save them for later so I can remember how the heck I built something.
1uF is too small for use with the LED strip. You’ll want something bigger, like the 1000uF as listed on the layout. :wink:

okay i hope i can keep testing with the 1uF though? well i did and its working with the 4 arms. next step is to pull it over to the teensy and add audio… i will keep you updated :slight_smile:

Hmmmm… when I try to compile it for the teensy it throws the following error:

In file included from FourHerzMain.ino:1:0:
/Applications/Arduino.app/Contents/Java/libraries/FastLED-3.1/FastLED.h:12:2: warning: #warning FastLED version 3.001.000 (Not really a warning, just telling you here.) [-Wcpp]
#warning FastLED version 3.001.000 (Not really a warning, just telling you here.)
^

i also tried to add those lines
void ChangePalettePeriodically();
void FillLEDsFromPaletteColors( uint8_t colorIndex);
void SetupPurpleAndGreenPalette();
void SetupBlackAndWhiteStripedPalette();
void SetupTotallyRandomPalette();

but it does not fix it. shite… :confused:

ah and another thing. the teensy has only 11 free pins after adding a audio shield. can i simply just use one clock as asked before? Thanks @Daniel_Garcia for all your support. Is there a possibility for FastLED Donations?

Are you sure you have the most recent version of the FastLED library? Delete the one you have and grab the latest again.

There’s 10+ more pins on the bottom of the Teensy 3.x. A little more tricky to solder to but you’re not out of pins yet!

It might not hurt anything to use that 1uF cap, but it’s so small it’s not really helping anything. Also, since you have 4 arms, ideally you would use 4 caps, one on each arm.

@Hen_Core I like to use these female headers so I can plug/unplug the Teensy (which has pins soldered on). This will give you plenty of room to have wires soldered to the bottom pads on the Teensy if you decide to go that route.

@marmil Yap. Thats what I did now :slight_smile: Hmm can’t test because Bounce2 seems not to work either:

^
/Applications/Arduino.app/Contents/Java/libraries/Bounce2/Bounce2.cpp: In member function ‘void Bounce::attach(int)’:
/Applications/Arduino.app/Contents/Java/libraries/Bounce2/Bounce2.cpp:24:10: warning: unused variable ‘read’ [-Wunused-variable]
bool read = digitalRead(pin);
^

hmm okay. now i compiled again and Bounce2 did not throw any errors… weird :slight_smile: will test now. I installed the latest FastLED Version but still prompts me

@Hen_Core My mistake, that “warning: #warning FastLED version 3.001.000” is normal and can be disregarded. @Daniel_Garcia added some stuff about version info to help with trouble shooting users code. If you’ve grabbed the current version and inside the library folder in the file “library.properties” it says verison=3.1.1 you should be good. (Apparently I was not awake as much as I thought I was this morning.)

okay :slight_smile: since this is going to be an art installation would be cool to have an idle animation. anyone keen to help me with that?