Arduino Due and TLC5940 LED Driver, Daisy Chain Issue

Hardware Arduino Due
1

Hi,

I am currently trying to daisy chain two TLC5940 LED drivers with an Arduino DUE. I have been using the library found here: Google Code Archive - Long-term storage for Google Code Project Hosting.. I have tried a single TLC5940 and it is functioning properly, however, I can not get a second TLC5940 to work.

I have made the same connections outlined in the source code:
TLC5940 pins -> ______ :
pin 17 SOUT -> pin 26 of TLC5940 2
pin 18 GSCLK-> Arduino DUE pin 3
pin 19 DCPRG -> 5V
pin 20 IREF -> pulled to ground with 10k
pin 21 VCC -> 5V
pin 22 GND -> GND
pin 23 BLANK-> Arduino DUE pin 4 with 2K pull up to 5V
pin 24 XLAT-> Arduino DUE pin 4
pin 25 SCLK -> Arduino DUE pin A.17 (SDA1)
pin 26 SIN -> Arduino DUE pin 18 (TX1)
pin 27 VPRG -> GND

And with the second TLC5940, have made the same connections except connecting SOUT of the first TLC5940 to the SIN of the second TLC5940. I have also changed the config file to indicate that there are 2 TLC5490s being used.

Has anyone been able to daisy chain 2 TLC5940s to an Arduino DUE with the library identified above? Is there something that is required that I am missing?

Thanks!!!

2

Hello!

I'm trying to get the DUE and the TLC5940 to work on a project.

Can you please confirm to me the following?

pin 23 BLANK-> Arduino DUE pin 4 with 2K pull up to 5V
pin 24 XLAT-> Arduino DUE pin 4

According to this, both pins BLANK and XLAT go to pin 4 of the DUE. Is that right or should XLAT go to pin 5?

pin 25 SCLK -> Arduino DUE pin A.17 (SDA1)

You say pin A.17 is SDA1. SDA1 is next to AREF on the board. I don't quite get what A.17 is. Could you please explain?

Thank you!
Franco.