RP2040 won't go to built-in USB loader

[ataradov]

Connectors look correct to me.

But the lack of enumeration from the host is on the host, not the device. May be capture a bit longer trace to see if host takes a couple seconds to start doing something.

The absolute minimal "USB device" is 1.5 kOhm resistor between 3.3 V and D+. This is enough for the host to reset the bus (both D+/D- low for ~100 ms) and send the device descriptor request. At this point host has no way of knowing if the device is real or just a resistor.

[SiliconWizard]

Not sure exactly what crossover you're talking about, but the pin right next to VBUS on the connector should definitely be D-, but looking at your layout, this pin seems connected to R2 (unless you've swapped the silkscreen), which is connected to D+ of the RP2040.

RP2040 pin 46 is DM and pin 47 is DP.  pin 2 of the USB connector connects to R2 which connects to pin 46.  pin 3 of the USB connector connects to R3 which connects to pin 47.  Is that backwards?

According to your schematic, R2 connects to pin 47, which is USB_P (D+). What did I miss?

By no crossover, I meant that you don't need to switch the USB lines from the connector to the microprocessor (ie they go straight to the uP).

Yes, of course. D+ of the connector to D+ of the MCU, and ditto for D-.

[phil from seattle]

Not super easy to read but here's what I sent to the fab.  The resistor numbers might be confusing. R2 is for the left resistor, R3 for the right. RP2040 on top, USB connector on the bottom.

[phil from seattle]

Thanks for all your help, I really do appreciate it. Tried without  a hub and on a different computer. no change.  I also buzzed out the USB connector and have continuity for all the pins on the connector.  Not sure what my next steps will be.

[ataradov]

Are you sure about that? It looks like labels are swapped either here or on the schematic. R3 is Pin46 and DM according to the schematic. This is the left resistor.

But the actual routing is correct. So, it must be some mixup with the labels.

Your next step is to figure out why PicoProbe does not work. There seems to be something really wrong with your computer.

You can even do the experiment with the resistor and you should see USB traffic, at least the SOFs and a request for the device descriptor.

[phil from seattle]

The labels are that way because there no room.

[ataradov]

Ok, but then your description "R2 is for the left resistor, R3 for the right" is not correct.  Resistor R3 is on the left.

[phil from seattle]

oof, you are right.  Not sure how I missed that.