Evie Salomon is developing new plug & play cartridge for C64 called BackBit.
It can read natively PRG, T64, P00, D64, D71, D81, 8K & 16K CRT, Disk2Easyflash CRT files.
Reading is almost as fast as reading from cartridge.
There's no need to come in directory to start game.
Filenames are not limited to 16 characters.
Easyflash CRT games will need to be converted to Backbit format, same as games with multiple D64 images.
Evie's words before 16 days:
"I am in process of ironing out final details. Here is the progress:
BACKBIT LEVEL I (work began Feb 2019)
The cartridge will load any single-file program, such as PRG, P00, T64, 8K & 16K CRT. It will even load 50K+ Action Replay PRG files that usually require a loader. It is recommended to use an unpacker tool (such as unp64) to reduce loading time since loading is instant. THIS LEVEL IS COMPLETE!
BACKBIT LEVEL II
The cartridge will emulate disk & sequential tape loading using KERNAL vector override. While this method is not foolproof, it does work on a lot of games, and for those that are not 100% compatible with this method, it does greatly reduce work necessary to get games working, often a patch of just a few bytes. Remaining tasks include full save support, random file access and possibly support for larger disks such as D71/D81. THIS LEVEL IS ESTIMATED COMPLETE IN A FEW WEEKS.
BACKBIT LEVEL III
The cartridge will support a banking system with a publicly released API indicating how to use the system. It can support 16K of data access at a time with access of up to 32GB total (the full capacity of the SD Card formatted to FAT32). There is a delay to switch banks, in which time the cartridge will be unavailable, but the CPU will not be held up (instead, polling can be done to detect when the operation is complete). THIS LEVEL WILL BEGIN ALPHA TESTING WITHIN A MONTH.
If there is enough demand I can make a batch of 10 cartridges for a beta test for a reasonable price. The cartridge firmware can be reprogrammed with a USB cable (no USB usage is planned for normal use, it is meant to be a standalone cartridge, and this may eventually be eliminated in favor of a SD card-based firmware update).
Meanwhile, support for D71 & D81 format is done.