Released a new “unofficial” version of the firmware for the Ultimate-64 / U2+ by Gideon.

Changelog:

Changes since official release (3.9 / 1.37)

• Fixed RGB mode (U64 only)
• Fixed block read command
• Fixed access of files with special chars in CBM disk images, accessed from IEC
• Fixed UCI issues with SidPlay and others
• Fixed colon issue in Ultimate Kernal ROM
• Fixed crash on invalid file chain CBM filesystems
• Fixed check order DIR / VOLUME; fixes some issues with exFAT directories
• Added M and V commands in modem emulation layer, V now supporting numeric responses. Thanks Scott Hutter
• Fixed the root cause of the VOLUME bit set in exFAT directories
• Fixed missing ‘probe’ for filesystems on multi-partition disks
• Fixed loading from wrong device ID when issuing the ‘run disk’ command
• Fixed many little bugs in the generation of CVT files (copying GEOS files from a disk image)
• Implemented writing CVT files back to a disk image (enables copying CVT files across disks.)
• Adopted changes to U64 Kernal to set default loading ID, as submitted by Leif Bloomquist
• Adopted USB modifier key handling, as submitted by Peter de Schrijver
• Corrected bug in extended partition table reading

Download:

• U2+ Unofficial Firmware (07/03/2021) (709)
• U64 Unofficial Firmware (07/03/2021) (685)

source: ultimate64.com github.com