I would like to connect two Blinkt in a series, I am powering the pi via GPIO, and would like to power both Blinkt with my existing power supply which I believe has enough amperage and connect both in series to the same GPIO ports, so that they do the exact same thing at the same time or close anyway. Is that to much current for the GPIO pins, if so guess I can run two if I use two different GPIO’s pins for the second one and modify the library?
Also, regarding quantities. Do you have 300 Blinkt, on hand ready to ship most of the time?
The Blink! needs 4 connections: Power, Ground, Data and Clock: http://pinout.xyz/pinout/blinkt
Power/Ground are the power supply for the pixels, this is where current will be drawn. The usual estimate for APA102 pixels (the ones on Blinkt!) is 60mA peak per pixel, for “FFFFFF” or bright white. For 8 pixels this is 480mA peak per Blinkt! In practise you’ll probably not hit this, but having a 2.5A power supply is a good idea anyway.
The Data/Clock lines are what control the Blinkt!, you can assume that no meaningful amount of current will be drawn from these pins. Because the Blinkt! never talks back to the Pi (it’s a one way signal from Pi -> Blintk!) you can safely connect two Blintk! or possibly even more to these same GPIO pins. They will display exactly the same thing at exactly the same time.
As for quantities, I’ll find out.