I am working on a project where I used a shift register 74HC595N which has hidden GND and VCC pins in Eagle. So I used the invoke property as shown in the pics, and connected the VCC and GND to the +5V and GND of the Arduino board. This connects the two hidden pins of the shift register directly to the Arduino. but in the PCB design phase, both pins are connected to random pins. Is there a way I can connect them explicitly from the schematic?

  • \$\begingroup\$ Look up "invoke" \$\endgroup\$ Commented Oct 7, 2014 at 13:35
  • \$\begingroup\$ i have just mentioned i used invoke and i illustrated this in the picture and it didnt work \$\endgroup\$ Commented Oct 7, 2014 at 13:36
  • \$\begingroup\$ Sorry about that. Not sure how what you're seeing is possible, other than maybe the "random pins" are actually tied to VCC and GND. Where do you actually have VCC and GND routed to in the schematic? \$\endgroup\$ Commented Oct 7, 2014 at 13:40
  • \$\begingroup\$ no they are not connected to VCC and GND , mu VCC and GND are routed to my arduino ass shown in the figure \$\endgroup\$ Commented Oct 7, 2014 at 13:45
  • \$\begingroup\$ I just see them leaving the page, but I can't see what they're connected to. \$\endgroup\$ Commented Oct 7, 2014 at 13:49

1 Answer 1


I added the same object in eagle now too and it works fine here.

Maybe the 'random' pins are also connected ground for example. If the shift register is closer to a component that is also connected to ground you will see a yellow line (from the unrouted layer) to that component.

To check if this is the case you can use the show function on the board layout screen. (you can use this function by typing show in the text bar) Then click on the yellow unrouted line. everything that is sharing the same net name (GND in our example, will light up. You can now easily check if the arduino ground pins are lighting up. Also the name of the net is showed in the bottom left corner of the screen once you used the show function.

  • \$\begingroup\$ thanks man they are really connected to VCC and GND but it was my fault i didn't see them well until i use the show button \$\endgroup\$ Commented Oct 7, 2014 at 13:53

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