v3l0c1r4pt0r / ucm4 Goto Github PK

Possible to add a superspeed USB C DRD, like dwc3?

So we can power the cm4 from a USB C host, and with gedged devices act as a offline / caching ipxe server, to install the host

It has to be shorted for a moment while connecting to power. The idea of how it looks like right now was to short it with tweezers, screwdriver or similar tool. Reality however is that it is really hard to make short good enough, so it is treated by bootloader as low state and rpiboot is entered.

On manufactured board, there is no via that connects mentioned test points to USB signal lines.

6mm through hole tact switches are way too bulky for such a small board. Smallest SMD ones would be sufficient to save space.

In version 0.1.0 soldermask clearance around vias is at JLCPCB's minimum. As a result some vias are soldermasked, some are not. Everything works, but such random pattern looks badly.

It seems that it is not properly centered and rotated. This has to be investigated further, before making any action. Especially rotation, as I based mine on original drawing.

For now this is reproducible only on autobom branch, but problem is deeper, as scripts on this branch simply extracts data from PCB and schematics.

kicad-randoms @ e5ce080

BTW, thanks for your amazing work, I love it.

This can make mounting harder and cause problems in factory.

While rpiboot works and PC successfully communicates via USB, there is a problem at later step. Reason could be wrong booting order. Activity LED not flashing error code could suggest that. Maybe some other software/firmware issue. Or simple soldering mistake on first handsoldered board.

There is a mistake in +5V power line. Near connection to CM4 with Hirose connector first two connections are fine, but to the other 4 pins it is by mistake 0.13 mm, instead of 1.2 mm.

Hi

Would you possibly be willing to help add GPIO16 and GPIO17 on your design to allow hardware flow control serial console ?

I have below a prototype build of a serial console to e-paper project which could be even better with a ucm4 board

Terminal using
https://github.com/vroland/epdiy

LCSC ran out of stock. Should be fairly easy to find alternative, as this is standard part.

LCSC ran out of stock. One alternative would be to use RT9742GGJ5, as AFAIR this was the original part. But I replaced it due to shortage. What is worse, almost no parts from Richtek's RT9742 series are available at the moment and using any one that is still available is very risky, as it can disappear at any time. If it is possible to use it is different story, haven't checked that.

Also it might happen that rotation is wrong, but it is hard to judge from just JLCPCB rendering.

Reproducible easily on autobom branch, but exists also on master.