turbo R (openMSX)¶

Background¶

A libretro core of openMSX, the MSX emulator that aims for perfection. It emulates the MSX1, MSX2, MSX2+ and turbo R computers, with C-BIOS machines that need no other BIOS and many real machines with their own ROMs, and extensions such as Konami's SCC, the FM-PAC, MSX-Audio, MoonSound and the GFX9000. It is preliminary.

The core is built for Linux (x86_64, aarch64), Windows (x64), macOS (Apple Silicon, Intel) and Android (arm64-v8a, Software video output only).

The openMSX core has been authored by

openMSX team
WizzardSK

The openMSX core is licensed under

GPLv2

A summary of the licenses behind RetroArch and its cores can be found here.

BIOS¶

None needed to start: the core carries openMSX's machines, extensions and scripts with the C-BIOS ROMs, and writes them to system/openmsx/share at its first start (and again after an update of the core, over its own files only). A real MSX machine (core option Machine) needs its system ROMs in system/openmsx/share/systemroms, otherwise C-BIOS MSX2+ starts instead; openMSX finds them there by their contents, whatever their names.

Extensions¶

Content that can be loaded by the openMSX core have the following file extensions:

.rom, .ri, .mx1, .mx2, .col, .sg, .sc (cartridges)
.dsk, .di1, .di2, .dmk, .xsa (disk images)
.cas, .wav (cassettes)
.m3u (lists of disks)
.zip, .gz

Disk images need a machine with a disk drive; the C-BIOS machines have none. Cassettes need a machine with BASIC.

Features¶

Frontend-level settings or features that the openMSX core respects.

Feature	Supported
Restart	✔
Screenshots	✔
Saves	✕
States	✔
Rewind	✔
Netplay	✕
Core Options	✔
Memory Monitoring (achievements)	✕
RetroArch Cheats	✕
Native Cheats	✕
Controls	✔
Remapping	✔
Multi-Mouse	✕
Rumble	✕
Sensors	✕
Camera	✕
Location	✕
Subsystem	✕
Softpatching	✕
Disk Control	✔
Username	✕
Language	✕
Crop Overscan	✔
LEDs	✕

A savestate loads only into the build of the core that made it. Run-ahead works. A cartridge's SRAM and the machine's settings are kept in RetroArch's save directory, in openmsx/.

Directories¶

The openMSX core's library name is 'openMSX'.

Frontend's System directory

openmsx/share/ (openMSX's machines, extensions, scripts and the C-BIOS ROMs, written by the core)
openmsx/share/systemroms/ (real machines' and extensions' system ROMs)

Frontend's Save directory

openmsx/ (openMSX's user folder: SRAM, settings)

Core options¶

The openMSX core has the following option(s) that can be tweaked from the core options menu. The default setting is bolded.

System¶

The MSX machine and the cartridges in its slots. Changes take effect when the content is loaded again.

Machine (Restart) [openmsx_machine] (C-BIOS MSX1|C-BIOS MSX1 (Europe)|C-BIOS MSX1 (Japan)|C-BIOS MSX2|C-BIOS MSX2 (Europe)|C-BIOS MSX2 (Japan)|C-BIOS MSX2+|C-BIOS MSX2+ (Europe)|C-BIOS MSX2+ (Japan)|Philips VG-8020 (MSX1, Europe)|Sony HB-75P (MSX1, Europe)|Toshiba HX-10 (MSX1, UK)|Yamaha CX5M (MSX1, Europe)|Philips NMS 8245 (MSX2, Europe)|Philips NMS 8250 (MSX2, Europe)|Sony HB-F700P (MSX2, Europe)|Sony HB-F1XD (MSX2, Japan)|Sony HB-F1XV (MSX2+, Japan)|Panasonic FS-A1WSX (MSX2+, Japan)|Panasonic FS-A1ST (turbo R, Japan)|Panasonic FS-A1GT (turbo R, Japan))

The MSX computer to emulate. The C-BIOS machines need nothing else; a real machine needs its system ROMs in <system>/openmsx/share/systemroms, otherwise C-BIOS MSX2+ starts instead. Europe and the UK run at 50 Hz.
Extension 1 to Extension 10 (Restart) [openmsx_ext1] to [openmsx_ext10] (None, or one of openMSX's extensions, by maker and name: Konami SCC and SCC+, Panasoft FMPAC, Sunrise MoonSound, GFX9000 and ATA-IDE, memory mappers, disk drives, MSX-DOS 2 and many more)

A cartridge or device in a free slot, as openMSX's -ext. Some need their ROMs in <system>/openmsx/share/systemroms. The extension options are shown up to the last one in use, and as many as the machine has free slots for.

Video¶

The size of the picture and its border.

Resolution [openmsx_scale] (Auto|1x (320x240)|2x (640x480)|3x (960x720)|4x (1280x960))

The size openMSX draws the picture at, borders included: 320x240 times this. Auto follows the screen mode: 1x for the 256 pixel wide modes, 2x for the 512 wide and interlaced ones.
Video Output (Restart) [openmsx_video_output] (Software|OpenGL)

Software hands RetroArch the picture as pixels, for any video driver. OpenGL draws through RetroArch's OpenGL context (the gl or glcore video driver), with openMSX's own scalers and effects. Android has Software only.
Crop Overscan [openmsx_crop_overscan] (Disabled|Enabled)

Shows only the part of the screen the MSX displays on, without its border; the size follows the screen mode.
Pixel Aspect Ratio [openmsx_pixel_aspect] (TV|Square)

TV: the picture as wide as on a TV, as openMSX shows it. Square: each pixel as wide as it is tall.

Controllers¶

The device for each port is chosen in Controls > Port ½ Controls > Device Type:

MSX Joystick (default): D-pad or left stick, A and B are triggers A and B; ports 1 and 2 are the MSX's two joystick ports.
Cursor Keys: for games played on the keyboard: the D-pad presses the cursor keys, A presses Space and B presses M.
MSX Mouse: RetroArch's mouse.
Arkanoid Vaus Paddle: turned by the mouse's horizontal motion, the left button fires.
Keyboard: nothing in the MSX port; the port's pad buttons can be remapped to keyboard keys.
None

With either RetroPad device, X presses Space, Y Return, Start F1, Select F5, L Esc and R Shift. L3 on port 1 shows the machine's details over the picture (Software output). A keyboard works as the MSX keyboard.