My favourite MSX is the Philips NMS8250. -- It’s got the perfect form factor, it fits under my monitor and I always have it on my desk in front of me. I’ve got a Moonsound, Music Module, FM-PAC and a MegaFlashRom (MFR) for the SCC. I love the different sound chips for the MSX.

But the 8250, no matter how wonderful, has one big fat problem: The audio mixer is broken by design. As soon as another sound cartridge is used, the PSG sound fades to inaudible. Even original Konami SCC cartridges sound wrong. So when I want to play a game or enjoy a music demo, I need to pull out another MSX which is obviously pretty inconvenient.

Recently I heard about the GR8NET. Initially I was curious about its network capabilities, but soon I found out it also comes with MSX-AUDIO, MSX-MUSIC, SCC and PSG on board. Plus all of these are connected directly to a LINE-OUT plug. With this cartridge the 8250 mixer is completely bypassed and I can finally enjoy the MSX that’s on my desk and connected to my speakers.

It only arrived some days ago and I’m still learning how to use it. It’s not the easiest device to use out of the box, so hopefully this guide will help new users (or existing users that keep their GR8NET in a drawer) make the most of it.


The GR8NET can be used in different “mapper modes” -- Kinda like memory configurations. I’m not sure about the details, but I found there’s 2 modes that are useful for regular use.

Mapper 0 is the default mapper when you start the MSX with the GR8NET in. This mapper can be used for updating the device, browsing remote Internet locations like BBS systems, programming network related software in BASIC, etc.

For games and demos using additional sound cartridges, it’s Mapper 8 you want. This mode also uses Nextor so you can access the data on the SD card. Type _netsetmap(24) and the msx will reset and start in mapper mode 8. You don’t want to be doing this all the time, so let’s make mapper 8 permanent.


Set mapper 8 as default

To make the GR8NET boot automatically to mapper 8, do this:




From here on, when starting the MSX, the GR8NET boots to Mapper 0, switches to Mapper 8 and reboots.

If you need to go back to Mapper 0, start the MSX while holding the down cursor key pressed.

You have to repeat this process after updating the GR8NET.

Installing SofaRun

Now prepare an SD card (formatting FAT16) and create a folder SOFARUN, copy the SofaRun files in there.

Also create a file (with Notepad, for example) and name it:


Inside this document write


(Where SOFARUN is the name of the folder where you kept the SofaRun files)

Don't worry if this file doesn't show in Windows, it's still there. I'm guessing it's being ignored for security reasons.

Now populate the SD with all the files you want to use. I made separate folders for GAMES, DEMOS, etc. The nicest way to work with SofaRun is to store your game roms in a zip file and access that zip from within SofaRun. This way you will see all your long filenames.


Booting Floppies

I’m using a Gotek in my 8250, so I want to be able to boot from the “floppy drive” too. In Mapper mode 0 this happens automatically. But when using Mapper 8, preference is given to Nextor and it’s gr8cloud and SD card.

When starting the MSX in Mapper 8, press and hold the N key. This disables Nextor and assigns the letter A: to the floppy drive (or Gotek, in my case) allowing it to boot.

For more boot-keys have a look here.


Line In

Rather than connecting the GR8NET to the amplifier, I opted for connecting it to my PC through the Line-In jack. Open the Sound Settings and set Input to "Line In" -- Now it's easy to change the volume and mix it in with the rest of the system sound, record nice quality and use my headphones. 


Too Loud

When I first connected the GR8NET the sound was way too loud. To make it more reasonable, I used:


Pick your own value to taste.


Windows Bluetooth Headset

I ran into a little nuisance when using my headset to listen to the GR8NET, for some reason the sound from Line-In isn’t available for Bluetooth. The silly solution is to go to Open Sound Settings, under Input go to Device Settings and there put a checkbox in front of Disable. Then remove the checkbox again. Now the Line-In audio should go to the Bluetooth headset too.

Hopefully by now you’ll have a pretty nice setup for the GR8NET cartridge and can easily access your favourite games and demos without constantly having to type stuff.

I’ll keep adding to this doc when I find stuff to improve the flow. Please drop me a note on twitter @bitsofbas if you need a hand.