I am a very big fan of the 'MATR' SDX tool. It mounts *.ATR files that it can see in the filesystem as if they were real floppy disks. I have recently had some issues with my SIO2PC-USB, so 'MATR' has become more useful than ever. Sadly, it does seem to have some of its own problems and I do not believe there are plans in the future to continue its programming. However, when combined with the PBIBIOS of the U1MB I understand it is now possible to use that device's 'SIDELoader' in the same way.
Which is good!
However for some reason I just cannot seem to work out how to mount an *.ATR image as a floppy drive using it! I can shell-out from SDX to the U1MB and then SIDELoader, attach the *.ATR but cannot for the life of me return to the same SDX session! It always reboots and loses the disk mount.
I wonder if someone could give me step-by-step instructions on how to do this?