It is possible to access the Pi from your computer with just a USB cable using an “Ethernet over USB” services known as RNDIS on windows. This allows you to SSH into the Pi. The process is described in detail here: https://desertbot.io/blog/headless-pi-zero-ssh-access-over-usb-windows
Also on the Adafruit website: https://learn.adafruit.com/turning-your-raspberry-pi-zero-into-a-usb-gadget/ethernet-gadget
Half way down the page are instructions for using Windows has a host machine. As mentioned, some of the time the Pi will appear as a COM port and not as a network adapter. Thus RNDIS will not work. The RaspberryPi forums provide some helpful guidance, if you read between the posts. The most useful posts are from May 13,2021 onwards.
I experienced this problem and corrected it. Below are my step-by-step instructions. NOTE: This assumes the Pi’s image is correctly configured for remote access as detailed in the links above.
- Plug the USB cable into Pi’s socket marked USB (NOT the one marked power).
- Plug the USB cable into your computer. After a few seconds, your computer should chime as it recognizes the device.
- Open the Device Manager control panel. (You can find it via the Windows search bar)
- Expand Network Adapters. If you see an entry “USB Ethernet/RNDIS Gadget”, you are good to go.
- If not, expand Ports. If you see an entry “USB Serial Port” (COMn). that may be the Pi. Unplug the USB cable from the computer. If the entry goes away, then that was the Pi and you need to continue with the following fix.
- Download the driver “Acer USB Ethernet/RNDIS Gadget” as suggested in the Jan 12, 2021 entry. The entry links to: https://www.catalog.update.microsoft.com/Search.aspx?q=32589075-1506-4042-9bc4-a3009153023b
- Click on the Download button on the Microsoft page. It will open another window. Clicking on the link within that window actually downloads the driver. (Using Chrome, I had to right click and “open in a new window” to get the .CAB file to download.)
- Open your Downloads folder to confirm it was downloaded. Extract the files to the Downloads folder
- Return to the Device Manager. Under Action, select add legacy hardware. The Add Hardware Wizard should appear. Click the Next button.
- Select “Install the hardware that I manually ….” and click Next
- Select Network Adapters and click the Have Disk button.
- Browse to the expanded CAB folder in Downloads and click on g_rndis.inf. Click on the Open button.
- Click on the OK button to install the driver.
- (I rebooted the system as standard practice, but I’m not sure if it’s necessary.)
- Not totally understanding why, I followed the suggestion from the May 13, 2021 post and used Windows Update as described below:
- Open Windows Update and check for updates.
- When the results are returned, click on “View optional updates”
- Expand Driver Updates. Select the Acer USB Ethernet driver. Click the Download and install button.
- After the driver is installed, reboot the computer.
- Wait until Windows completely finished rebooting and starting all the background tasks.
- Open the Device Manager.
- Plug in the Pi’s USB cable
- Hopefully, when you hear the chime, the Pi will appear as a Network Adapter.
I hope this procedure works for you as it did for me. If not, (or if I missed a step), please leave a comment below.
Fredric Raab 