0

Device Descriptor failed for ATmega32u4 based board
Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.

Device Descriptor failed for ATmega32u4 based board

by Kepler25 on Tue May 15, 2018 1:15 pm

I've designed an Arduino compatible board based on the Feather 32u4 Bluefruit LE. I'm using the exact same microcontroller configuration (3.3V, 8 MHz) as the Feather. I'm using a Caterina-Feather32u4 bootloader.
I've implemented a breadboard version of a barebones Feather (reset switch, USB & VBUS capcacitors, 8 MHz resonator, USB circuitry). Interestingly, the breadboard version works like a charm everytime. The controller shows up as a Feather32u4 and I can upload programs through the Arduino IDE easily.
When I solder the same controller on my PCB and connect it to my computer, I get a device descriptor failed error.
-I've tried multiple USB cables. No effect.
-I've checked solder connections. All are fine.
-I can see the bootloader working, since the led on pin 13 dims and brightens slowly.
-I have the latest relevant adafruit drivers. (v 2.2.0.0).

Any suggestions on how to resolve this?

Kepler25
 
Posts: 4
Joined: Tue May 15, 2018 12:25 pm

Re: Device Descriptor failed for ATmega32u4 based board

by adafruit_support_mike on Tue May 15, 2018 11:23 pm

You'll probably need to check the D+/D- signals on an oscilloscope.

If a high-speed circuit that works in the breadboard stops working on a PCB, it often means the signals have become noisy without the breadoard's parasitic resistance and capacitance damping out the rising and falling edges. You need to see what the signals are doing before you can plan a fix though.

adafruit_support_mike
 
Posts: 54052
Joined: Thu Feb 11, 2010 2:51 pm

Re: Device Descriptor failed for ATmega32u4 based board

by Kepler25 on Wed May 16, 2018 1:28 am

Resolved it. Apparently, the resonator I used was 16 MHz, while the bootloader was configured to 8 MHz. Worked like a charm when I soldered the correct resonator!

Kepler25
 
Posts: 4
Joined: Tue May 15, 2018 12:25 pm

Re: Device Descriptor failed for ATmega32u4 based board

by adafruit_support_mike on Wed May 16, 2018 11:02 pm

Glad to hear you got things working. Happy hacking!

adafruit_support_mike
 
Posts: 54052
Joined: Thu Feb 11, 2010 2:51 pm

Re: Device Descriptor failed for ATmega32u4 based board

by luthier42 on Fri May 18, 2018 4:29 pm

Kepler25 wrote:I've designed an Arduino compatible board based on the Feather 32u4 Bluefruit LE. I'm using the exact same microcontroller configuration (3.3V, 8 MHz) as the Feather. I'm using a Caterina-Feather32u4 bootloader.


I have a similar project board that I'm working on and I can't get Arduino IDE to recognize it, no port is shown. I was able to burn the standard bootloader thru the IDE using my Uno as an ISP. How is the Caterina bootloader different? How can I burn that one instead? I have a USBTiny ISP and AVRDudess recognizes the chip and reads the fuse bits. Thanks!

luthier42
 
Posts: 14
Joined: Mon Sep 04, 2017 10:22 am

Re: Device Descriptor failed for ATmega32u4 based board

by adafruit2 on Wed May 23, 2018 12:10 pm

please note - if you are designing your own PCBs, with your own modules, we provide zero support or assistance with hardware/firmware/software. you are completely on you own!

adafruit2
Site Admin
 
Posts: 17671
Joined: Fri Mar 11, 2005 7:36 pm

Please be positive and constructive with your questions and comments.