Please somebody help me out. I have 120 ws2811 rgb pixel per strip. I am programming on arduino uno. How many strips can i able to connect to my arduino uno. I want to run 20 strips parallel connecting to single board i.e., 120 * 20=2400 pixels . All the 20 strips should have to run in same pattern at a time. I have individual power supplies. Power supply is no issue at all.
Kindly let me know which development gives me this option to run 20 strips. How much distance i can able to connect because i need to cover 50 metres of distance.
You can’t off of an uno. It takes 3 bytes of ram per pixel which means you need a minimum of 7200 bytes of ram - the uno only has 2k. There’s games you can play to get around this, but it involves some pretty advanced use of the library and is mostly unsupported. I’d recommend looking at something like the teensy 3.2 to make sure you have enough ram.
As for wiring and distance, I would recommend using twisted pair for the wiring, this makes longer distances work a bit better.
Finally, I’d strongly encourage you to look into parallel output if you want any kind of decent frame rate. 2400 leds in a row will take you 72ms to write out a single frame - which means that, realistically, you won’t be able to animate more than 10 frames per second.
You might be able to run them all off one data pin, but 20 is a lot of strips and you might need some kind of boosters or level shifters to ensure that there’s enough power coming from the one pin
If you really want your 20 strips to ALWAYS be identical then as Jeremy suggests you may be able to run all 20 from the same data pin however, that long distance to the strips may cause some problems to the data signals.
If you use all the UNOs 14 digital output pins and set the 6 Analog input pins as digital outputs that would give you exactly the 20 pins you are asking for this project.
I was wondering if there is an easy way to get FastLED to simultaneously output the exact same data stream on multiple data pins !?
thanks daniel sir. But if i use teensy 3.2 can i run on single data pin or else should i need 1 data pin for 1 strip. Hence, then i need to change the program code for more data pins.
actually, i am writing a program for 120 pixels. i have 20 strips of 120 pixels each. I want to connect data pin parallel to 20 strips for identical. Same pattern should follow in each strip with out delay between in strips.
@Vijay_Kumar1 If you have all the strips and the Arduino UNO on hand, I suggest you just try to connect all 20 strips to that single data pin.
The problem you may see would be due to the capacitive loading of all 20 data wires between the single data pin and the strips. That MAY cause the data signal to be too distorted to be valid. SO make sure that all 20 wires would be exactly the length that you would have in your final setup. Good luck !
yeah, i understood what you are telling. if i go with teensy 3.2 as suggested by daniel sir. then how should i wire. should i use 1 data pin for 1 strip or can i use 1 data pin for 20 strips. Please let me know as i new to this.
@Vijay_Kumar1 Because you want to drive data to only 120 pixels, unless you want to do very complex animations or you have other functions that need extra ram and/or processor power the UNO may very well be sufficient for your usage.
Note that Teensy has a lot more ram and processor speed BUT it has 3.3V outputs that you will need to go through some level translator to get a 5V data signal that your strips need. The UNO already gives you 5V data output.
Also, same as with the UNO, I do not think that you can have the same data sent via 20 different pins on the Teensy either. Daniel may be able to confirm that.
It seems to me the best approach is to somehow use a single pin and distribute that data signal to the input of your 20 strips but you may have to introduce some data driver chips like the SN74HCT245 which can handle 8 data lines so you may need 3 of them.
I may help with more details if you described precisely your strips physical layout. How far is the processor (Uno or Teensy or …) from each of the 20 strips ?
can i join 1 arduino uno to another one, upto 20 boards from the output of 1st board to the input of 2nd board, output of 2nd board to the input of 3rd board like wise upto 20 boards. for synchronizing all the boards.