Usb64 fails to load a ROM less than 1MB in size when padded with `0xff` from makemask

[networkfusion]

Expected Behavior

Usb64 should load a ROM less than 1MB in size (padded with 0xff from makemask)

Current Behavior

Padding a ROM using makemask when under 1MB causes USB timeouts and other issues. This occurs because the padding is 0xff.

Possible Solution

Removing the 0xff padding from the file, allows it to be loaded as expected.

Steps to Reproduce

test roms.zip

Context (Environment)

Windows 10 Usb64 from #17 a bat file with the following commands: <path-to-exe>\usb64.exe -rom=%1 -start X7 running OS 3.05

Detailed Description

Possible Implementation

Fix in firmware, or at worst, remove the padding from the ROM before it is loaded over USB (although that might not fix when loaded from SD).