! A-Star 32U4 is not being recognized

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1

Hi,

I’m trying to connect to my romi robot by connecting it to my computer via USB. Previously, by following the instructions here, I was able to get it to work. However, after a week or so, now the romi robot is not connecting. In the device manager, under the Universal Serial Bus controllers, there is a “Unknown USB Device (Device Descriptor Request Failed)” whenever I connect my robot. I checked the hidden devices, and under Ports (COM & LPT), I found something similar to “Pololu A-star (COM 5)”, which was greyed out. I tried uninstalling the greyed-out devices with Pololu A-star (COM #) and the A-star bootloader too in order to try and factory reset it, but that didn’t do much.

I tried to reinstall the a-star 1.3.0.0 drivers (which is provided by the manual), but it still didn’t work, so then I installed the a-star 5.1.0 drivers, which again didn’t work. I tried restarting my computer, but that didn’t work either. What should I do?

Operating system: windows 10 64-bit.
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EDIT: When I went to reinstall, I realized that the “would you like to install this device software” popup doesn’t show up. Did I fully uninstall the drivers correctly by uninstalling devices? If not, how should I do so? Because the devices on the device manager are gone.

^ Update: actually it’s probably because I have Always trust software from “Pololu Corporation” on.

EDIT #2: I’ve tried to do the same process on a fresh computer running Windows 11. I’ve installed the a-star drivers 1.3.0 (the device software popup install did show), I connected the new computer to the romi robot, and once again, the only thing I see is “Unknown USB Device (Device Descriptor Request Failed)”.

FYI: I know the robot is connecting since I hear the USB connecting sound from windows. Also the green light on the robot turns on, and 3 other usbs blink at startup. I’ve also tried different ports.

Here’s some more info:
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Information:

Device USB\VID_0000&PID_0002\5&a0fcac8&0&4 was configured.

Driver Name: usb.inf
Class Guid: {36fc9e60-c465-11cf-8056-444553540000}
Driver Date: 06/21/2006
Driver Version: 10.0.19041.4474
Driver Provider: Microsoft
Driver Section: BADDEVICE.Dev.NT
Driver Rank: 0xFF0000
Matching Device Id: USB\DEVICE_DESCRIPTOR_FAILURE
Outranked Drivers: usb.inf:USB\DEVICE_DESCRIPTOR_FAILURE:00FF2000
Device Updated: false
Parent Device: USB\ROOT_HUB30\4&1a6e0085&0&0

image

2

Hello.

It sounds like your computer is having problems communicating with the Romi; can you verify that your USB cable works as expected to communicate with (not just power) other devices? If your USB cable is able to transfer data with another device successfully, I recommend following the instructions in the “Reviving an unresponsive Romi 32U4” section of the Romi 32U4 Control Board user’s guide. There are a few different methods described there, so if you’re having problems getting one to work, you can try the others (I generally recommend trying them in order).

Brandon

3

A week or 2 ago, it was working perfectly fine, with the programs being downloaded correctly. I’m using the USB A to micro-B cable provided directly from the Romi Robot Kit for FIRST, so there shouldn’t be any issue. The cable may have potentially been broken though. How should I test the data transfer? I don’t have any special devices to connect the USB A to micro-B cable to. Do you have any suggestions?

EDIT: I found a spare USB A to micro-B cable that isn’t the one provided from the kit. This one doesn’t work either. I got the same exact result.

I’ve also found 2 other cables. When I try connecting these two cables to the robot, my computer doesn’t even recognize that something has been connected (there’s no USB connection sound, no new device showing up in the device manager).

Also, if possible, could you tell me how to fully uninstall the drivers so I can try reinstalling them?

4

Okay, thank you so much! I think I got it to work. For reference: I followed the Reset Button solution, clicking the reset button on the romi twice to make it enter bootloader mode. This was done while the robot was still connected to the computer by the USB A to micro-B cable. For some reason, the computer actually recognizes the pololu robot when it is in bootloader mode, as shown here:
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Now, while it is in bootloader mode, upload code via Arduino (using the blink LED code is fine). Also note that you have to change the port to where the romi is connected to. Now, windows will recognize the port and everything should work fine.

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