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Topic: 2 TLC5940 problem, possible overload? (Read 3670 times) previous topic - next topic

Brad Burleson

Just for fun, here is a set of 3 multiple TLC5940 examples.

The first is an ATmega168 w/ 2x TLC5940's running off 3 "AA" batteries (missing 6 LEDs due to no space).
The second is an ATmega168 driving a custom board with a pair of TLC5940's.
The last example has a board with an ATmega168 w/ 1x TLC5940 (w/ 1x LED) connected to another board w/ 2x TLC5940's.

I even did a lousy video (no audio, fan noise?) also http://youtu.be/DT54VHR94eo

Make sure you change NUM_TLCS in tlc_config.h... I spent several hours re-checking my wiring because I'd forgotten that I'd changed tlc_config.h on my laptop install, not my desktop.  So when I ran BasicUse the LEDs on the 2nd TLC5940 would light at random.

You can tell if you've made a mistake with NUM_TLCS when not all the LEDs are lighting with BasicUse but the fade is still smooth with no "gaps" (times with no LEDs fading).

Double-check your wiring and you should be good to go.  Then follow Demonic69's advice and try a tlc.setAll(4000) (followed by a tlc.update) to make sure you can light everything at once.

FWIW,

Brad (KF7FER)



funkyguy4000

Oh wow! Yea, I'm still working on it.  I'm trying to figure out whats wrong with the code by using just 1 tlc5940.  Once i get that, i'll update it to support another tlc5940.
Thx
Accelerate to 88 miles per hour.

Demonic69

I've got a working 8x4 setup with 2 TLCs. If you want to post your latest code I can test it out for you if you like mate.

funkyguy4000

will do, I will send that over when i get home from classes.  My laptop doesn't have the code, but my desktop does.
Accelerate to 88 miles per hour.

funkyguy4000

Hello.

I know its been a while although I've gotten the Atemega328p standalone and am using a 3.7 v lipo battery to run that along with 32 leds that are driven by 2 TLC5940's.

I'm using the Fades example with 5v into analog 0 and I have an issue where the first 16 leds fade properly but the second set of 16 leds blink all funky. 

Any suggestions?                                                                                                                                                                                                                                                                                                                                               
Accelerate to 88 miles per hour.

Brad Burleson


I'm using the Fades example with 5v into analog 0 and I have an issue where the first 16 leds fade properly but the second set of 16 leds blink all funky. 

Any suggestions?                                                                                                                                                                                 


I've seen that happen when I have more TLC5940's than defined by NUM_TLCS.  I'd double-check that value just in case.

FWIW,

Brad.

funkyguy4000

my NUM_TLCS value is at 2, and i'm using 2
Accelerate to 88 miles per hour.

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