Protoshield wiring schematic


Hi all (and @gordonb),

I’ve uploaded a wiring schematic for the protoshield to my GitHub repository. This schematic should help clarify how to wire the Grove connectors. Please let me know if you have any comments or questions.


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Great :slight_smile: Thanks @adrianlu.
This will be an enormous help for a person who has not played around with any raspberries of Arduinos or whatnots :slight_smile:


This is awesome, thanks!


That is so cool!Thanks!


@adrianlu great work.


created this document that shows the sensors, the API id, Arduino port, etc. I find it helpful when debugging.
port definition.pdf (21.2 KB)


@adrianlu, in your blog, you say that there are several ways to connect the 12V supply and 12V-GND to the corresponding Grove connector pins … do you have any particular suggestion? in your pictures, I can see some of these cables are together and go somewhere but I can’t see the connections … thank you in advance


Hey @pauanta, I found it difficult to connect multiple wires to the Grove connector pins. So, I connected the supply and ground pins on the 12VDC Grove connector to a male-male jumper wire via a wire-wrap wire. The other male end of the jumper wire then allowed for enough space to connect all of the modules supplied by the 12VDC module.

Hope this helps. Let me know if you need me to clarify.


@adrianlu many thanks, this was very helpful! another question we have is the following: for sockets 7 and 8, where can I connect the pins for ALPN2 12V and ALMI 12V in the Arduino?


@pauanta, socket 7 and 8 are not actually connected to the Arduino, socket 9 is. Socket 9 is connected to the relay switches for ALPN2 and ALMI.


Got it! I forgot to take into account that those sockets were for the relay switches. Then, we are ready to test the different elements of the micro-controller. Thank you !


Hi Adrian,
Thank you for sharing this. I am afraid I’m a bit of a novice at this… I don’t really understand how the protoshield is connected to the Arduino Mega and the Base shield.
Furthermore there appears to be Grove receptacles on the protoshield (S1…S9) according to the image on the ElectronicsSchematicLarge.pdf but I don’t see how they get there. Am I supposed to solder them onto the shield? I did’t see these receptacles in the BOM…
It would be helpful if you could upload some images of how everything is connected… can you do that pleae ?

Thanks in advance.


Hi @Peperoni

Welcome to the club of Never seen a Arduino Mega Pie before :slight_smile:

The Grove connectors that you see soldered on the Arduino Shield are indeed missing from the BOM.
You will need to order them. I got mine from here a online store in Germany.
Here is a link so you know what to get :slight_smile:
Grove universal 4-pin connectors


That’s great, thanks !
Did you manage to assemble the arduino with the grove protoshield ? I don’t see how this fits…:frowning:


Not yet. Just got my connectors and plan to work on them tonight.
I’ll keep you posted on how it connects :slight_smile:

It might require a special tool to make it fit.


Hey @Peperoni,

Sure! I can send you some images of my protoshield. Let me get back to you before the end of the weekend.

It was a bit confusing for me too until I had all of the parts in front of me. Have you seen my post on the assembly of the protoshield here?

Once you have the protoshield assembled, you’ll notice that the protoshield “stacks” on top of the Arduino Mega via the headers. Then the Grove Base Shield stacks on top of the protoshield also via the headers.

Hope this helps! Let me know if you have any more questions.



Thanks Adrian. Your blog was quite helpful. However… I get the impression that my protoshield differs from yours. I got one from Arduino and in the image below you can see the contents of the package…
I gues I need to order additional components to get it fixed to the Mega properly and be able to mount the Grove Base shield on top of it.


Hi @adrianlu,

I’m looking at your schematic and I just wanted to confirm something about the 12V connection.
Wondering if my assumption is correct.
12V DC is taken from the 12V power supply.
It provides +12V and -12V.
Referring to the schematic,
+12V is connected to the following; 12V, AACR-12V, AAVE-12V, ALPN2-12V, ALMI-12V.

  • 12V is connected to GND-12V.

I’m just asking cos if this is correct we have S1 and S7 with all pins in +12V.
Hope I’m correct :slight_smile:


Hey @silversson,

Yes, that sounds correct. Current will flow from the +12V terminal to the -12V terminal. S1 and S7 are indeed connected to +12V.


Hello everybody,
I’ve just started to build this wiring and i use this schematic. There is something i can’t understand. What does mean 12v in et 12v out ? And why the 12v out wiring is separated in 4 parts ?
Thanks for your help,