@Yves_BAZIN first test after hooking it up: 7/8 data lines running flawlessly, no problem running off of 1 usb battery.
now to troubleshoot why my 8th data line isn’t working… not sure if hardware or code… as soon as I get it fixed I’ll post pics!
@Sam_Guyer great job with the libraries - defining strips and sending data is totally seamless (once I got the newer esp32 core!)
Which pins are you using ?
@Yves_BAZIN ran up one side of a dev board - 12,14,27,26,25,33,32,35
its my 8th strip that doesn’t work. pin 35. switched it over to the other side of the board to pin 18 and still no dice. also rigged it to another strip, and same thing. Also swapped just that line to a new shift register and still the same thing…
and switched my ordering around in software as well (which messes up my mapping but at least I can see whats up) and the same line is dead/flickering like it has a floating signal
EDIT:
got it working 
when I switched up my pins I had an off by one error and was on pin 19, not 18. now it works!
culprit was pin 35. maybe its protected and can’t be used for RMT? Or maybe I have a bum dev board
@chad_steinglass , ESP8266 only has 8 way parallel output, so you picked correctly with ESP32.
As for power, given that I do the same thing as you do, you are likely to run low with 2.1A. My shirt with 1730 pixels tends to go up to 5A or so on some patterns.
http://marc.merlins.org/perso/arduino/post_2018-05-29_EDM-Party-Shirt-powered-with-FastLED_NeoMatrix-and-Adafruit_GFX_-plus-160Wh-10Ah-4S-worth-of-lipos.html shows the power system I use, which basically is a 16V lipo with its voltage taken down to 5V via a step down converter that can provide 10A.
I also have those mega USB battery packs, but at the time I felt they would not deliver enough amps. If you find a USB-C one that give you 4 or 5A, that may be better, but 2A seems like barely enough.
@Marc_MERLIN I hear ya on power… I guess I’ll have to see how bright I want it to get… for parties around NYC I like to keep it pretty low so so as not to blind everyone (and also so I don’t overheat!)
…but on playa that might be another matter all together… I might want to be able to be my own portable art car 
@chad_steinglass gpio 35 can only be set up as input not ouput
@Yves_BAZIN that would do it! I guess I’m glad it only set me back an hour
Also found, when I hooked up my controls, that not everything can be used as an analog input either, but after figuring out the pin 35 issue, that part was easy
both you and @Marc_MERLIN - I think I’m going to need more power after all… with a single USB battery, its bright enough for an indoors party, but nowhere near where I want it to be on playa
Marc - I like your big lips idea, but I love the ease of the USB power banks… my power bank should theoretically be able to output 4.2A without a problem on two different ports, so I might try splitting my power bus and just driving it off of two ports…
I know I’m not supposed to tie power and ground together on two sources (is that right?) or else they’ll fight… but as long as I tie grounds together, I hope my signal should be fine, right?
thanks!
Oh - also: missing/deleted image from Google+
@chad_steinglass https://www.espressif.com/sites/default/files/documentation/esp32_datasheet_en.pdf
You will find all the possible usage of the pins
@chad_steinglass that’s impressive !!!
@chad_steinglass you can use 2 USB battery packs and tie their ground. You don’t need to tie their Vcc, just plug them into different panels and they won’t fight
@Marc_MERLIN thanks Marc! I just split it into 3 for good measure, one each for the left side, right side, and back (and the ESP32 draws power off to the right side panel, so it doesn’t need its own plug). Maybe overkill and I might go back down to 2, but with 3 I can crank the brightness without a problem
Your issue with big USB packs is that they take way too long to recharge and now you have to monitor 3 packs. A lipo can be charged in 1h. You should still consider something like this https://www.amazon.com/gp/aw/d/B00J3MHTYG?psc=1&ref=yo_pop_mb_pd_title
https://www.amazon.com/gp/aw/d/B00J3MHTYG?psc=1&ref=yo_pop_mb_pd_title
Thanks Marc - I’ll look into that 
Here’s my little set up for now. I need to take a break and enjoy the sun before it’s gone. Little black case holds the shift register, clear case holds the esp32 and input/output connectors, and the guy that looks like a face is my manual control box, with a pot for brightness and 2 buttons - one to cycle pattern, one to cycle color palette
Next step is web/Bluetooth - I haven’t ever tried that before!
Thanks for everyone’s help this morning! Went from simply soldered and cut strips on a vest to a working project, my first esp32 use, and my first step above 4 parallel outputs, all in a morning
missing/deleted image from Google+
@Marc_MERLIN hmmm I have some old 14.4V 7800maH laptop batteries from my very first attempt at LED costumes for my first burn in 2014 when I was using 12V RGB LEDs… they’ve been sitting for years but maybe I’ll break them out and see if I can’t get them to work still… I figure if some laptops will go through one of those batteries in 3-4 hours, and they’re 112 WH, then that means they must be capable of putting out at least like 30watts, which should be plenty.
now to grab one of the voltage regulators you mentioned
@chad_steinglass yeah, expect laptop batteries to be capable of putting out 30 watts easily. I think mine can do 100W+ and generally LiIon batteries have low internal resistance, and can put out 10 to 50A without sweating.
Glad to see I won’t be the only one with a FastLED shirt at Burning Man
@chad_steinglass I forgot to say that your vest looks really cool. Now get prepared to spending way too long writing code for it, although hopefully you can take my existing code to get a head start
@Marc_MERLIN I have some standard stuff that i run on everything, but it’s pretty basic… I’m definitely planning to dive into the work that you did porting over the ledmatrix library to get text and stuff going too
I’m sure I’ll be bugging you and yves again soon!
@chad_steinglass feel free to ping me when you get there. you can choose between Adafruit::GFX text (simple, but not as fancy, although it does what I need) and LEDMatrix Text which is a lot more fancy but also harder to use (scrolling in multiple directions and letters with more than one color within each letter, should you want what).
So I went back to one power bus and hooked up the voltage converter you recommended to the 14v laptop battery - works like a charm and is as bright as the sun!
But I’m actually still getting limited… voltage on my bus drops into the 4s when I turn it up, and I think drops below 3.5 or so when I really crank it, which then makes the controller die.
I THINK I’m getting 5V off the converter - the voltage drop must be occurring over my power wires between the battery and where it gets distributed out. Going to do some tests. But my power cables are definitely getting toasty. Using 22AWG right now, might have to go to 18!missing/deleted image from Google+