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Unintended or Intended Connections on P2 (USB-C) ICED-Right Rev.1.2b? #11

Open Nobody2303 opened 6 years ago

Nobody2303 commented 6 years ago

I detected some things on this connector which were a bit questionable.

VSS had a small contact on the right side of P2 with VSS line. I don't expect that this was inteded, as it would mix GND line (which is the Wire Shielding, grounded by the PC) with the internal grounding potential VSS. Am I right on this?

Re-routed GND Line

image

Next is the routing at the RX1 and TX1 pads. Initially RX1 and TX1 were wired like displayed on the picture below. Which means RX1 is constant +5V and TX1 is constant VSS.

image

I re-routed that like displayed below. Would this change be correct or did I miss some detail that would explain the deciscion with RX1 == +5V and TX1 == VSS?

image

Nobody2303 commented 6 years ago

It's even worse as I've just seen.

Per Defininition pinning is like named here (derived from JAE Datasheet) image

Application of Pin Names is displayed in this picture (also derived from datasheet) image

Thus Nomenclature of Pins is wrong as plus and minus for RX and TX are missing and RX2&TX2 are not appearing in pinnings and thus RX1 and RX2 are connected. Has there be some rework done and wasn't updated here on git? Or did I miss the general Idea behind it why it makes sense to do it that way?

haata commented 6 years ago

Looks fine in the gerbers? This was done a while ago (we always tend to use the nightly builds at the time to do pcb things) and sometimes KiCad messes things up unexpectedly.

The RX2+, TX2+, TX2-, TX1-, TX1+, RX1- and RX1+ are done in a way that it's compatible with earlier USB 3.0 (non-C) connectors so it works with the interconnect. And also works when rotating the cable.

The labels you see in KiCad are from the MCU, not the connector itself (RX1 and TX1 are for UART1).

Nobody2303 commented 6 years ago

I also switched with the files to KiCAD 5.0 that might also be an issue as there have been bigger changes made to Library handling Nethandling etc. Didn't expect it to possibly cause stuff like this... So it could be SW Version dependent... :/ (newer is not always better)

So could it be problematic if one would use a USB 3.0 Port to connect the first Ergodox Board as it's connecting T/RX2 an T/RX1?! Sorry but i'm so deep regarding USB 3.0 and USB Type C connectors.

Generally thanks for your fast reply! Was afraid the repository would be half dead :D