Options
Open games, save or load progress, manage disks, and change system settings.
iMSX2
User Guide
MSX · MSX2 · MSX2+
Your complete guide to iMSX2
Load games, customise the controller, use video filters, manage multi-disk titles, save your progress, and configure a real MSX BIOS.
01 · Controls
Everything is one tap away
The toolbar handles emulator features while the virtual pad can act as a joystick, cursor keys, or MSX keyboard keys.
Video filter
Choose None, CRT, Scanlines, or CRT + Scanlines.
Fast forward
Toggle higher emulation speed. The icon turns blue while it is active.
Edit controls
Move the virtual pad and buttons, then save a separate layout for each orientation.
Keyboard
Show or hide the software keyboard for games and MSX applications.
Full screen
Hide the toolbar and controller. Tap the screen to restore the interface.
What does Type mean?
A ROM mapper is the memory layout used by larger cartridge games to make different parts of the ROM available to the MSX. iMSX2 normally detects it automatically. If a game does not start or behaves incorrectly, use Type to try Normal, ASC8, ASC8 SRAM, ASC16, ASC16 SRAM, Konami SCC, Konami, or ASCII16-X.
Virtual controller
Joystick or cursor keys
Open Options › Directional Control to switch the D-pad between the MSX joystick port and keyboard cursor keys.
Per-button keyboard mapping
Make controls fit the game
Use Options › Button Mapping to assign Space, Enter, Tab, Esc, Backspace, cursor keys, or F1–F5 while a control is held.
Tip
Moving the on-screen buttons
- Tap the controller icon in the toolbar.
- Drag the D-pad and buttons to comfortable positions.
- Tap the controller icon again.
- Choose Save, or restore the default layout.
Portrait and landscape positions are stored separately.
02 · Open a game
From file to first game
iMSX2 accepts ROM cartridges, disk images, and ZIP archives directly from the Files picker.
- 1
Open Options
Choose Options (☰) from the toolbar.
- 2
Select Open Game
Choose Open Game from the Game Management section.
- 3
Choose a supported file
Select a
.ROM,.MX1,.MX2,.DSK, or.ZIPfile. iMSX2 loads it and starts automatically.
ROMMX1MX2DSKZIP
03 · Display & speed
Choose the way your MSX looks
You can choose the way your MSX looks while a game is running.
None
A clean, unfiltered image.
CRT
Softens the image to resemble a display tube.
Scanlines
Adds distinct horizontal raster lines.
CRT + Scanlines
Combines the CRT treatment and scanlines.
Fast forward
Tap the forward icon once to enable it and again to return to normal speed. A blue icon and an on-screen message confirm the current state.
Full screen
Hides the toolbar, background, and virtual pad. Tap anywhere on the emulation screen to bring the interface back.
04 · Saving progress
Continue exactly where you left off
Save states capture the complete emulator state so you can resume from exactly the same moment.
1
Open Options
The game pauses while the menu is open.
2
Choose Save Data
iMSX2 stores one quick-save state for the current title.
3
Choose Load Data
The local state is loaded first; iCloud is checked when no local state exists.
05 · Disk games
Single disks, multi-disk sets, and writable media
iMSX2 has a simple compatibility path and a native floppy path for titles that need real drive behaviour.
Without a Disk BIOS
Compatibility mode
- Works with one DSK image
- Quickest way to try a disk
- No live disk swapping
- Limited hardware compatibility
With a recognised Disk BIOS
Native floppy mode
- Best hardware compatibility
- Multi-disk games
- Drives A and B
- Insert, replace, eject, and swap disks
A
Import disks together. Select multiple DSK files and confirm their order. The first image is inserted into drive A.
B
Change disks while playing. Open Options › Manage Disks and choose drive A or B.
C
Create a user disk. iMSX2 keeps this writable disk between sessions for games that save to floppy.
Optional · Custom BIOS
Configure a custom MSX BIOS
C-BIOS is included and remains the default for ROM cartridges. A custom machine BIOS is optional, while a recognised Disk BIOS unlocks native floppy support.
A valid BIOS set consists of three files: the Main BIOS, Sub BIOS, and Disk BIOS. The Main BIOS file is always 32 KB; the Sub and Disk BIOS files are 16 KB each.
Choose one machine
Decide which MSX model you want to emulate. Do not mix files from related models or regional variants.
Select the three files
Open Options › Select BIOS and choose Main, Sub, and Disk BIOS. File names do not matter; contents and sizes do.
Check detection
A recognised set shows the detected machine and floppy controller. If a warning appears, verify that all files belong together.
Load your game
ROM cartridges can continue using C-BIOS. DSK games will use native floppy mode when the Disk BIOS is valid.
Examples recognised by iMSX2
These model names are examples only. iMSX2 does not provide proprietary BIOS files or download links.
| Machine | Generation | Floppy controller |
|---|---|---|
| Philips NMS 8250 / VG 8235 | MSX2 | WD2793 |
| Sony HB-F700 | MSX2 | WD2793 |
| Panasonic FS-A1F | MSX2 | TC8566AF |
| Panasonic FS-A1WX | MSX2+ | TC8566AF |
| Sanyo PHC-70FD | MSX2+ | TC8566AF |
Available without a connection
A quick guide is built into iMSX2
Open Options › Help for a compact version of the essential instructions. It covers controls, save states, disks, and BIOS setup even when the device is offline.
Troubleshooting
Common questions
Do I need a custom BIOS to play ROM cartridges?
No. iMSX2 uses C-BIOS by default. A custom BIOS is optional for ROM cartridges.
Why can I not swap disk images?
Disk swapping is available only in native floppy mode, which requires a recognised 16 KB Disk BIOS.
Why is my BIOS combination not recognised?
Check the required file sizes and make sure Main, Sub, and Disk BIOS files come from the same exact machine and region.
Why does a ROM fail to start?
Automatic mapper detection covers many known titles, but some files may require a manual selection from the Type menu.