μ3D: RatRig V-Core 3 EVA wiring over RJ45

I put the modules up for sale on Tindie!

This weekend I soldered the RJ45 and JST-XH connectors. I did some electrical tests and so far everything seems to work perfectly.

I also printed the "cable holder" and "universal cable mount" from the EVA 2 GitHub repo (printed really quickly with super low quality on my poor CR-10). Everything fits perfectly.

The module can also be mounted "upside-down" for those who prefer.

The PCBs arrived quicker than expected: less than 2 weeks.

I ordered a whole bunch and I'm happy to send them to whoever wants to help with initial testing and validation.

I will solder two boards with RJ45 and JST-XH connectors this weekend, and run a few tests on my own.

If all is good then I'll create a special product listing on Tindie for those who want to try out some boards free of charge (you pay shipping).

In v.2 I added M3 mounting holes to screw the ADXL directly to the PCB.

In v.3 I replaced those mounting holes with 8-pin 2.54mm header holes at the top of the PCB.

This would make it possible to either:

1. solder the ADXL with 8-pin headers directly to the PCB, or
2. solder an 8-pin socket and then simply slide the ADXL (with pin headers) into the socket

The pin assignments on the 8-pin headers is identical to the ADXL board, and would use the twisted pairs 1-2 for GND/SCL, 3-6 for SDA/VCC, 4-5 for SDO/CS. The INT1 and INT2 would remain unconnected in this case.

Personally I don't really like v.3 because it's not flexible and forces you to use specific twisted pairs for the pins. In v.1 and v.2, you can choose which pairs to use and easily add your own decoupling capacitors if needed.

I guess I can leave it to the community for suggestions on which board is better.

I really wish I thought of this before ordering the first batch of PCBs. Well this is going to be part of the v.2 boards: Mounting holes for an ADXL.

Probably not everyone wants to mount a PCB on another PCB, but at least this would avoid the need to 3D print an ADXL adapter, since you can just use some M3 screws to attach the ADXL at the top of the PCB (the holes flanking the logo). It can be mounted on either side of the PCB and cleanly wire to the JST-XH connector.

This design is by far not final, as I'm also considering just adding 8 pins to solder the ADXL directly to the PCB.. we'll see.

I'm not sure if this will be the final design, but I ordered a set of PCBs for prototyping and testing.

I'll update the project in ~2 weeks once I receive them.

Note: I plan on selling the first few batches of these boards on Tindie (populated/unpopulated) as well, before publishing the design files on GitHub.