Create a virtual disk – MSX-DOS

How to create a MSX-DOS virtual diskette. Virtual diskette that can be copied to a real diskette if necessary to work with your MSX.

Why would you do that? Simply because your MSX starts on MSX-Basic and it is often necessary to go through MSX-DOS for multiple operations. Especially the launch of some games and applications.

For the story:

The integrated BIOS of a MSX does not support disk drive. This is why the connection interface of an external disk drive for MSX is provided with its own BIOS extension in the form of a 16KB ROM associated with the disk controller and containing, the Disk-Basic programmed by Microsoft, the kernel (or Kernel) MSX-DOS programmed by Microsoft, and the driver programmed by the interface manufacturer.

With the first MSXs equipped with an internal disk drive on the market, the ROM extension was integrated into the internal disk controller. This resulted in the loading of an additional cartridge containing the interface and thus the release of a port. The launch of the MSX-DOS is then automatically dice when a diskette containing the MSXDOS.SYS and COMMAND.COM files is inserted into the drive when it is initialized.

Procedure:

The procedure we will detail here is done under BlueMSX, the non-excellent emulator for MSX, MSX2, 2+ and turbo R.

Launch your emulator and then create a new diskette of the capacity of your choice:

Do File>Disk drive A>Insert new disk

I chose a record of 720 Ko. The .dsk file is immediately created in the directory of your choice.

Then download the two files needed to create a MSX-DOS diskette.

MSXDOS.SYS

COMMAND.COM

Place them in a folder and then in BlueMSX, do:

Files>Disk Drive B>Insert Directory

Formatting a virtual diskette:

In the MSX-Basic command guest start by formatting your A diskette.

CALL FORMAT

Validate with the key Enter.

Here is what you should get on screen.

Drive name? (A,B)

Type

A

The following line appears:

1 – Single Side
2 – Double Side
?

Type

2

Strike a key when ready

Then press any key on the keyboard.

If the operation went well, here is what is written:

Full format
OK

Copy the necessary files for MSX-DOS:

To copy the two files needed to create a MSX-DOS diskette, type the following. You must always be in the configuration or you have loaded in the second disk drive B the folder comprising the two files COMMAND.SYS and MSXDOS.COM.

COPY « B:*.* » TO « A: »

All files are copied from drive B: to drive A: (So on your virtual diskette in .dsk)

Check that all files have been created by typing:

files

You should see if you went well:

MSXDOS.SYS COMMAND.COM

Here's your MSX-DOS disk is created. Make a reset by booting on your diskette A, you will see that the MSX-DOS loads directly.

Loading MSX-DOS with a boot from your new virtual floppy.