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I am setting up a new development computer with FreeDOS and can boot off the SATA or USB drive. This is my first new computer with sophisticated UEFI (I have CSM enabled).
If I boot from the USB I will see the USB as C: and the SATA as D:. However if I boot off the SATA, DOS does not see the USB drive.
I suspect the FreeDOS USB driver is not doing what it is suppose to but it seems wrong that DOS sees it if it was used for a boot?
Has anyone experienced this problem and found a solution?
The FreeDOS kernel doesn’t support USB drives on its own.
When you boot from a USB drive, the CSM makes it available through the BIOS 13h services, so it appears to DOS as a “standard” drive and everything works fine.
When you boot from your SATA drive, the CSM doesn’t set anything up for your USB drive (although in some cases it can be induced to do so) and DOS doesn’t see it. To access the drive in that case, you need to install and configure a USB driver; FreeDOS provides the usbdos package for this purpose.
