2021 Jun 25, 07:57 PM
Please first resolve the power connection issue. The hc595 should get 5v and GND from the Pi e.q. the top power rail.
The second power supply should only go to JD_VCC and adjacent GND.
If that is done, read on.
The capacitor voltage isn't that important. 16V is sufficient but if the environment is likely to be very hot in the summer than a higher voltage cap could be a little bit easier for the cap in those stressful times. It's a little bit bigger cap though.
What else to order? Well, it depends what you want to do. Solving this issue and never touch electronics again or wanting to learn more about it and optimize the setup in the years to come? Having an assortment of resistors and caps is always good.
The first thing I would do is once the prototype works is removing the breadboard with the long noisy wires and move the hc595' to a more permanent place on a perfboard. I always have several perfboards in stock and use them a lot. The cost nearly nothing and you can make nice stable circuits on it. And you can practice you soldering skills if needed. :-) By the time you want to move that way it is better to start another topic.
For the shutdown button I honestly see no use. If I repeatedly wanted to shutdown a system I would make a desktop shortcut to putty with a commandline to execute. Effectively a "one-click-shutdown".
The second power supply should only go to JD_VCC and adjacent GND.
If that is done, read on.
The capacitor voltage isn't that important. 16V is sufficient but if the environment is likely to be very hot in the summer than a higher voltage cap could be a little bit easier for the cap in those stressful times. It's a little bit bigger cap though.
What else to order? Well, it depends what you want to do. Solving this issue and never touch electronics again or wanting to learn more about it and optimize the setup in the years to come? Having an assortment of resistors and caps is always good.
The first thing I would do is once the prototype works is removing the breadboard with the long noisy wires and move the hc595' to a more permanent place on a perfboard. I always have several perfboards in stock and use them a lot. The cost nearly nothing and you can make nice stable circuits on it. And you can practice you soldering skills if needed. :-) By the time you want to move that way it is better to start another topic.
For the shutdown button I honestly see no use. If I repeatedly wanted to shutdown a system I would make a desktop shortcut to putty with a commandline to execute. Effectively a "one-click-shutdown".