USB pads on Teensy 3.2 not working?

My prototype of a small MIDI-controller was working fine as long as it was on breadboard. Now I'm trying to use these https://www.benl.ebay.be/itm/274958617109?var=575239312093 to connect to the Teensy that sits inside an enclosure, by wiring USB V+, D-, D+ and GND to the pads on the bottom of the Teensy, but the board isn't showing up in the Tools->Port menu of Teensyduino, neither does my DAW find the MIDI device.
Double checked wiring, all is fine. Connecting through the standard Micro USB socket of the board works fine, both from Teensyduino as from within MIDI software. Replacing the above USB-C connector with an USB-A bus didn't help. What am I doing wrong? Micro USB has 5 wires, but I don't see why connecting only V+, D-, D+ and GND wouldn't work. I don't use any external power, just the USB +5V, and the above USB-C bus has only the mentioned connections.

TIA!
 
OK. Perhaps you can share a close-up photo of your wiring? I agree it should work as you described.

Paul
 
This really should work. I'd check the power first. If you're getting proper 5 volts on VIN-GND, then check the D+ and D-. Maybe they're swapped?
 
Assuming you are using a USB-A to USB-C data cable, is there a way for you to measure continuity of the 4 signals from the USB-A connector to the corresponding pads on the Teensy 3.2? Also please check for shorts between those 4 signals.

Paul
 
Maybe we could help more if we could see close-up photos of the actual wiring?

IMG_7603.jpeg
hmmm... not the perfect shot and D- looks very close to V+ on the USB-C bus breakout, but in reality it looks better than that. No shorts between any of the lines and all of them have perfect conductivity.
I tried the same with an USB-A bus, with the same result. I tried swapping D+ and D-, same problem.

The USB cable between my MacBook and my Teensy is the same I successfully use for my Launchpad, so it's a data capable one.

Thanks for looking into this!
 
Did you cut the trace between VUSB and Vin? With the trace cut the 5v from the USB port won't make it to the teensy.
 
Have you tried measuring the USB power while it's plugged in? Use a mutimeter in DC voltage mode, measuring between VIN and GND on Teensy. Is there really 5 volts power?

Looks like other people have experienced problems with this JRC-B008 product (which looks like JRC-BCC8 in some photos, JRC-B038 in others), where PCs don't send 5V power because it's missing the proper resistors on the CC pins.

https://electronics.stackexchange.c...c-b008-for-usb-c-microcontroller-power-supply

Before soldering a resistor, try using a USB A to USB C cable between this thing and your PC. The main idea is to plug into a USB A port on your PC, which always transmits 5V power. USB C ports might not send 5V power unless they see the proper hardware. USB A ports always output 5V power.
 
Looks like Adafruit sells this JRC-B008 part (or did previously) but without the nice panel mount holder.

https://www.adafruit.com/product/5180

Their site has "It may not work with power supplies or ports that require CC resistors for PD negotiation."

Here's the PCB layout from Adafruit's images, in case anyone's curious how it's really wired.

jrc-008.jpg
 
...try using a USB A to USB C cable between this thing and your PC. The main idea is to plug into a USB A port on your PC, which always transmits 5V power. USB C ports might not send 5V power unless they see the proper hardware. USB A ports always output 5V power.

This is being very helpful, Paul! From an USB-A port on my desktop computer, connecting via an USB A to USB C cable, my controller works 100%.
Now I have to figure out what resistors I need and where to solder them to make a USB-C port send 5V. MacBook Air just having 2 of those. The information I need should be in here http://ww1.microchip.com/downloads/en/appnotes/00001953a.pdf but my very basic knowledge and the small size of the pins are making me sweat a little ;).
 
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