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I'm trying to build a pump from Instructables, with no experience at all. I appear to be pretty close but the 5V line from the Arduino does not power the driver or LCD screen via my perfboard, it works fine on a breadboard. See the complete schematic here:

enter image description here

The arduino is powered without USB, so the 12 current flows as intended, but the driver and LCD is not powered (via the 5v). The schematic is a bit confusing to me, I made a connection in the red highligted area in the next pic, but it isn't drawn as connected in the schematic?

enter image description here

And on the arduino, the two gnd pins by the 5v are greened out, what does this mean?

enter image description here

I also haven't tested the encoder yet, but it looks like it is not powered? Can it be powered by the data pins directly?

Appreciate any advice.

EDIT: I checked some ground connections with the multimeter, the following are connected:

enter image description here enter image description here

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    \$\begingroup\$ Beware that much of the material on sites like instructables is of dubious quality. You should not be powering a motor driver through an Arduino. Whoever wrote this seems to have proposed some goofy power supply scheme involving unwise and unnecessary modifications to the Arduino board. \$\endgroup\$
    – Chris Stratton
    Commented Jul 23, 2019 at 14:38
  • \$\begingroup\$ It looks like your two 5 V circuits are isolated from each other (red lines?). \$\endgroup\$
    – evildemonic
    Commented Jul 23, 2019 at 14:53
  • \$\begingroup\$ It looks like that in the schematic, but I soldered a connection where I highlighted in red marker in pic #2. Or did you mean they are still isolated? @ChrisStratton I can imagine. This was an official university student competition (IGEM) project, I assumed they had proper supervision, maybe not. I still want it to work though.. I have seen a ton of builds where the driver is powered from arduino though. If you google a4988 nema17 arduino. \$\endgroup\$
    – user2406501
    Commented Jul 23, 2019 at 14:56
  • \$\begingroup\$ Sorry, I missed that you made that connection. \$\endgroup\$
    – evildemonic
    Commented Jul 23, 2019 at 15:05
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    \$\begingroup\$ References to a "schematic" are in error because you don't have one - you have an unlabeled pictogram. That right there is a huge red flag as it makes the sanity of the design hard to review. \$\endgroup\$
    – Chris Stratton
    Commented Jul 23, 2019 at 15:14

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