One of the final things missing from the Yellow MSX series of kits for the RC2014, is the ability to access typical MSX storage devices (floppy and cassette).

Without storage such as this, its hard to claim that we have achieved full MSX compatibility.

There are plenty of schematics online for how to give the MSX access to cassette storage.  Its not a very complicate design -- that is the easy part - although I have yet to get a working old-timey cassette player that works - so that makes it hard to test and validate cassette storage!

For the floppy interface, I considered designing something based on the work of Dr. Scott M. Baker (https://www.smbaker.com/z80-retrocomputing-part-14-rc2014-floppy-controller-boards).  I have actually built one of his designs for the RC2014 CPM configuration - and its worked well - it would only need the appropriate software driver written to support MSX-DOS/Nextor.

But I decided to go for a different and slightly more modern approach and create a USB interface for the system.  Based on the very cheap and easy to source CH376 modules.  There has been a fair bit of effort by some members of the MSX community to support this module.  The work done to date was invaluable to get the software and hardware working: 

https://github.com/S0urceror/MSX-USB 

https://www.msx.org/news/en/use-your-msx-as-an-usb-keyboard

http://rookiedrive.com/en/

https://github.com/Konamiman/MSX

By going with USB it gives me:

* A more reliable access to floppy - purchasing cheap new USB drives, will be more reliable than attempting to use old used floppy hardware.

* Aside from floppy, we can access many other storage systems: flash storage, USB HDD, etc - making it easy to transfer files from a PC to the system

* Other device types can be considered - if the software can be written - such as network interface, serial interface, keyboards - so many possibilities - although the software work is quite demanding.

I have uploaded 3 videos that shows the work in progress for access floppy, flash storage.  The driver written to-date, currently supports many USB thumb drivers - and I have tested the floppy access for 2 floppy drives (an older IBM/Teac drive and a brand new no-brand drive from ebay)

It took an enormous effort for me to learn how to access drives over usb, how to use the various USB protocol/standards for floppies, flash and hub access.  The software still has more work -- it currently is about 8k in length.   

The video shows an early version of the PCB and schematic.  It changes a bit.  With better physical support for the CH376 module and the layout for the cassette design (cassette is yet to be tested and validated)