Daisy chain LED bars

Products & Technology Grove
#1

Is it possible to daisy chain two LED bars, using only one digital port? I have two Grove LED bars (<LINK_TEXT text=“https://www.seeedstudio.com/Grove-LED-B … -2474.html”>https://www.seeedstudio.com/Grove-LED-Bar-v2-0-p-2474.html</LINK_TEXT>)… I can hook them up to separate digital ports (eg D7 and D8), but instead I’d like to do this:

  • Use only one digital port
  • Go from D8 on the Grove shield into one LED bar
  • Connect GND, VCC, DCKO, and DO, into GND, VCC, DCKI, and DI of the second LED bar
  • In my code, make only one call to bar.setBits(value)



    Is this possible? When I tried this, the LEDs on both LED bars were synced up and matched each other. In other words, when I called

    bar.setBits(0b0000011111);

    …the first 5 LEDs on both LED bars were lit (and the remaining LEDs were off). I was expecting the first 5 LEDs to be lit only on the first LED bar. So is it possible to daisy chain multiple LED bars, and control their LEDs independently?
#2

Hi there,



You can chain Grove - LED Bars by connecting DO, DCKO, VCC, GND to another LED bar’s DI, DCKI, VCC, GND. But seems library in Seeed Wiki only can used with one LED bar, I wrote a new library to you. Please download the following files:



<LINK_TEXT text=“https://raw.githubusercontent.com/Seeed … r/LEDBar.h”>https://raw.githubusercontent.com/SeeedDocument/Projects/master/led_bar/LEDBar.h</LINK_TEXT>

<LINK_TEXT text=“https://raw.githubusercontent.com/Seeed … LEDBar.cpp”>https://raw.githubusercontent.com/SeeedDocument/Projects/master/led_bar/LEDBar.cpp</LINK_TEXT>



and put them to your project folder, let it looks like this:




[code]
#include “LEDBar.h”

LEDBar bar(9, 8, 2);

void setup() {
bar.begin();
}

void loop() {
bar.setBits(0x01f);
}
[/code]

The code above can make two LED bars looks like this:







Best Regards,

Blu