Hi, I am trying to control 5 RGB LEDs using two 74hc595 shift registers. I tried this on Wokwi and on a breadboard before finally soldering the layout. No with the soldered version I just don't get it working properly anymore. This is the general layout (here in Wokwi, but with more unrelated comp…

You need to fix up the connections. Strive for this quality. [U] [T] [E] Review these: [image] Share tips you have come across General Electronics Circuit Prototyping Construction A new user eventually asks: “Now that I have made my circuit work on …

Although I'm a little puzzeled as to why you have 3 white leds, as you can only drive 2 and 2bits from 1 register. You are correct! The 5th LED is of course not white, but violet, the green LED is off. Could you explain what that death pin is doing in the code? I don't quite understand it I am a…

Ah I get it. You were able to simulate the isse. Okay, that means I have a high on the data pin for some reason, right?

[image] loetamateur: Could you explain what that death pin is doing in the code? I don't quite understand it I am afraid. Should I add this wire? My little joke :grin: It's to introduce the "kiss of death" to the setup, by shorting the second register data input to HIGH. Reproducing what is …

Ah, okay. So I guess using these solder brides to connect neighboring pins is not really the way to go :sweat_smile: I think I have all the parts to try the whole thing again. To place these small (30 AWG?) bare wires, I probably need to buy proper tweezers. Thanks for all the good information. That…

I've been following this but not been able to help as I've not spotted anything that would cause a problem. However, one thing to note is I never solder ICs directly into prototype board, I solder a socket into the board then plug the IC into the socket. Doing so makes them a lot easier to replace i…

Yes, that is definetely a lesson I learned here.

[image] loetamateur: So I guess using these solder brides to connect neighboring pins is not really the way to go It can be done, but your ideal tools would be a fine point soldering iron with fine gauge solder wire. And good eyesight :slightly_smiling_face:

[image] loetamateur: You are correct! The 5th LED is of course not white, but violet, Binary output (lower left) 5 x 001 for all Red, but with Death Pin high... [DeathPinActivated]

[image] loetamateur: So I guess using these solder brides to connect neighboring pins is not really the way to go [image] loetamateur: To place these small (30 AWG?) bare wires, I probably need to buy proper tweezers. For neighboring pins, strip a good amount of insulation off the wire…

For these direct connections between neighboring pins it would need to be a lot thinner than what I currently use (25 AWG) though right?

Chaining of shift registers not working

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LarryD March 23, 2025, 9:06pm 32

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Chaining of shift registers not working

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