Usage Instructions

January 23, 2026 ยท View on GitHub

NOTE: These instructions are made by reference from the original nukedyt/Nuked-SC55 and jcmoyer/Nuked-SC55 documentation.

Supported Models

  • SC-55mk2/SC-155mk2 (v1.01 firmware is confirmed to work)
  • SC-55mk1 (v1.0/v1.21/v2.0 firmwares are confirmed to work)
  • CM-300/SCC-1 (v1.10/v1.20 firmwares are confirmed to work)
  • SCC-1A
  • SC-55st (v1.01)
  • JV-880 (v1.0.0/v1.0.1)
  • SCB-55/RLP-3194
  • RLP-3237
  • SC-155

ROM Handling

You can either put the ROM files in the same directory as the emulator or use -d, --rom-directory argument to load roms from a specific directory.

And based on the ROM's hashes the emulator will load the apropriate mode correctly unless you use --legacy-romset-detection.

Files should be names as such:

SC-55mk2/SC-155mk2 (v1.01):
R15199858 (H8/532 mcu) -> rom1.bin
R00233567 (H8/532 extra code) -> rom2.bin
R15199880 (M37450M2 mcu) -> rom_sm.bin
R15209359 (WAVE 16M) -> waverom1.bin
R15279813 (WAVE 8M) -> waverom2.bin

SC-55st (v1.01):
R15199858 (H8/532 mcu) -> rom1.bin
R00561413 (H8/532 extra code) -> rom2_st.bin
R15199880 (M37450M2 mcu) -> rom_sm.bin
R15209359 (WAVE 16M) -> waverom1.bin
R15279813 (WAVE 8M) -> waverom2.bin

SC-55 (v1.00):
R15199748 (H8/532 mcu) -> sc55_rom1.bin
R1544925800 (H8/532 extra code) -> sc55_rom2.bin
R15209276 (WAVE A) -> sc55_waverom1.bin
R15209277 (WAVE B) -> sc55_waverom2.bin
R15209281 (WAVE C) -> sc55_waverom3.bin

SC-55 (v1.21):
R15199778 (H8/532 mcu) -> sc55_rom1.bin
R15209363 (H8/532 extra code) -> sc55_rom2.bin
R15209276 (WAVE A) -> sc55_waverom1.bin
R15209277 (WAVE B) -> sc55_waverom2.bin
R15209281 (WAVE C) -> sc55_waverom3.bin

SC-55 (v2.0):
R15199799 (H8/532 mcu) -> sc55_rom1.bin
R15209387 (H8/532 extra code) -> sc55_rom2.bin
R15209276 (WAVE A) -> sc55_waverom1.bin
R15209277 (WAVE B) -> sc55_waverom2.bin
R15209281 (WAVE C) -> sc55_waverom3.bin

CM-300/SCC-1 (v1.10):
R15199774 (H8/532 mcu) -> cm300_rom1.bin
R15279809 (H8/532 extra code) -> cm300_rom2.bin
R15279806 (WAVE A) -> cm300_waverom1.bin
R15279807 (WAVE B) -> cm300_waverom2.bin
R15279808 (WAVE C) -> cm300_waverom3.bin

CM-300/SCC-1 (v1.20):
R15199774 (H8/532 mcu) -> cm300_rom1.bin
R15279812 (H8/532 extra code) -> cm300_rom2.bin
R15279806 (WAVE A) -> cm300_waverom1.bin
R15279807 (WAVE B) -> cm300_waverom2.bin
R15279808 (WAVE C) -> cm300_waverom3.bin

SCC-1A:
R00128523 (H8/532 mcu) -> cm300_rom1.bin
R00128567 (H8/532 extra code) -> cm300_rom2.bin
R15279806 (WAVE A) -> cm300_waverom1.bin
R15279807 (WAVE B) -> cm300_waverom2.bin
R15279808 (WAVE C) -> cm300_waverom3.bin

JV-880 (v1.0.0):
R15199810 (H8/532 mcu) -> jv880_rom1.bin
R15209386 (H8/532 extra code) -> jv880_rom2.bin
R15209312 (WAVE A) -> jv880_waverom1.bin
R15209313 (WAVE B) -> jv880_waverom2.bin
PCM Cards -> jv880_waverom_pcmcard.bin (optional)
Expansion PCBs -> jv880_waverom_expansion.bin (optional)

SCB-55/RLP-3194:
R15199827 (H8/532 mcu) -> scb55_rom1.bin
R15279828 (H8/532 extra code) -> scb55_rom2.bin
R15209359 (WAVE 16M) -> scb55_waverom1.bin
R15279813 (WAVE 8M) -> scb55_waverom2.bin

RLP-3237:
R15199827 (H8/532 mcu) -> rlp3237_rom1.bin
R15209486 (H8/532 extra code) -> rlp3237_rom2.bin
R15279824 (WAVE 16M) -> rlp3237_waverom1.bin

SC-155 (rev 1):
R15199799 (H8/532 mcu) -> sc155_rom1.bin
R15209361 (H8/532 extra code) -> sc155_rom2.bin
R15209276 (WAVE A) -> sc155_waverom1.bin
R15209277 (WAVE B) -> sc155_waverom2.bin
R15209281 (WAVE C) -> sc155_waverom3.bin

SC-155 (rev 2):
R15199799 (H8/532 mcu) -> sc155_rom1.bin
R15209400 (H8/532 extra code) -> sc155_rom2.bin
R15209276 (WAVE A) -> sc155_waverom1.bin
R15209277 (WAVE B) -> sc155_waverom2.bin
R15209281 (WAVE C) -> sc155_waverom3.bin

Emulator Running

  • SC-55mk2/SC-55mk1 buttons are mapped as such (currently hardcoded):
Q -> POWER
W -> INST ALL
E -> INST MUTE
R -> PART L
T -> PART R
Y -> INST L
U -> INST R
I -> KEY SHIFT L
O -> KEY SHIFT R
P -> LEVEL L
LEFT BRACKET -> LEVEL R
A -> MIDI CH L
S -> MIDI CH R
D -> PAN L
F -> PAN R
G -> REVERB L
H -> REVERB R
J -> CHORUS L
K -> CHORUS R
LEFT -> PART L
RIGHT -> PART R
SCROLL WHEEL UP (On Volume Knob) -> INCREASE VOLUME
SCROLL WHEEL DOWN (On Volume Knob) -> DECREASE VOLUME
LMB + MOUSE MOVEMENT (O Volume Knob) -> ADJUST VOLUME
  • JV-880 buttons are mapped as such (currently hardcoded):
P -> PREVIEW
LEFT -> CURSOR L
RIGHT -> CURSOR R
TAB -> DATA
Q -> TONE_SELECT
A -> PATCH_PERFORM
W -> EDIT
E -> SYSTEM
R -> RHYTHM
T -> UTILITY
S -> MUTE
D -> MONITOR
F -> COMPARE
G -> ENTER
COMMA -> ENCODER L
PERIOD -> ENCODER R
RMB (On Volume Knob) -> PATCH_PERFORM
SCROLL WHEEL UP (On Volume Knob) -> INCREASE VOLUME
SCROLL WHEEL DOWN (On Volume Knob) -> DECREASE VOLUME
LMB + MOUSE MOVEMENT (O Volume Knob) -> ADJUST VOLUME
SCROLL WHEEL UP (On Encoder Knob) -> ENCODER R
SCROLL WHEEL DOWN (On Encoder Knob) -> ENCODER L
LMB + MOUSE MOVEMENT (O Encoder Knob) -> ROTATE ENCODER

These are the options to use the emulator frontend:

General options:
  -?, -h, --help                                 Display emulator argument information.
  -v, --version                                  Display version information.

Audio options:
  -a, --audio-device <device_name_or_number>     Set output audio device.
  -b, --buffer-size  <size>[:count]              Set buffer size, number of buffers.
  -f, --format       s16|s32|f32                 Set output format.
  --gain <amount>                                Apply gain to the output.
  --disable-oversampling                         Halves output frequency.

MIDI port options (default, unless set to serial):
   -pi, --portin      <device_name_or_number>    Set MIDI input port.
   -po, --portout     <device_name_or_number>    Set MIDI output port.
 
Serial Port options:
   -st, --serial_type RS422|RS232C_1|RS232C_2    Set serial connection type
   -sp, --serialport  <serial_io_port>           Set the serial port/named pipe/unix socket for serial I/O.

Remote Control options:
   -rc, --remote-control <named_pipe>            Set the name of the named pipe to be opened by emulator.

Emulator options:
  -r, --reset     none|gs|gm                     Reset system in GS or GM mode. (No GM in MK1 1.00 & 1.10)
  -n, --instances <count>                        Set number of emulator instances.
  --no-lcd                                       Run without LCDs.
  --nvram <filename>                             Saves and loads NVRAM to/from disk. JV-880 only.

ROM management options:
  -d, --rom-directory <dir>                      Sets the directory to load roms from.
  --romset <name>                                Sets the romset to load.
  --legacy-romset-detection                      Load roms using specific filenames like upstream.

Accepted romset names:
  mk2 st mk1 cm300 jv880 scb55 rlp3237 sc155 sc155mk2 

ASIO options:
  --asio-sample-rate <freq>                      Request frequency from the ASIO driver.
  --asio-left-channel <channel_name_or_number>   Set left channel for ASIO output.
  --asio-right-channel <channel_name_or_number>  Set right channel for ASIO output.

These are the options to use the emulator renderer:

General options:
  -? -h, --help                Display emulator argument information.
  -v, --version                Display version information.
  -o <filename>                Render WAVE file to filename.
  --stdout                     Render raw sample data to stdout. No header

Audio options:
  -f, --format s16|s32|f32     Set output format.
  --disable-oversampling       Halves output frequency.
  --gain <amount>              Apply gain to the output.
  --end cut|release            Choose how the end of the track is handled:
        cut (default)              Stop rendering at the last MIDI event
        release                    Continue to render audio after the last MIDI event until silence

Emulator options:
  -r, --reset     none|gs|gm   Send GS or GM reset before rendering.
  -n, --instances <count>      Number of emulators to use (increases effective polyphony, but
                               takes longer to render)
  --nvram <filename>           Saves and loads NVRAM to/from disk. JV-880 only.

ROM management options:
  -d, --rom-directory <dir>    Sets the directory to load roms from. Romset will be autodetected when
                               not also passing --romset.
  --romset <name>              Sets the romset to load.
  --legacy-romset-detection    Load roms using specific filenames like upstream.

MIDI options:
  --dump-emidi-loop-points     Prints any encountered EMIDI loop points to stderr when finished.

Accepted romset names:
  mk2 st mk1 cm300 jv880 scb55 rlp3237 sc155 sc155mk2

Regarding Serial IO

With version 0.5.3, the emulator supports Serial IO for SC-55mkII and SC-55st. And with version 0.5.6 the emulator has support for Multi-Instance serial mode.

Regarding Setting up Virtual serial IO. Please read these instructions for Linux and Windows.

Regarding Remote Control

With version 0.6.3, the emulator supports Virtual Remote Control. Currently the Remote Control Client runs on Python and the emulator needs to be launched first to create the Named Pipe through which the Remote Control Client Connects.

So to use Remote Control first you need to launch the emulator with the argument: -rc <named_pipe> or --remote-control <named_pipe>

If you're using the python version of the remote client, you need to install the following modules: pygame (All platforms) and pywin32 (For Windows only)

Then launch the remote with the command: python remote_control.py <named_pipe>

Or run the converted executable in
Windows command prompt by using: remote_control <named_pipe>
or on Linux and MacOS: ./remote_control <named_pipe>

Regarding SRAM and NVRAM

With version 0.5.4, the emulator supports SRAM saving for SC-55mk1, SC-55mk2, JV880, SC-155, SC-155mk2 and NVRAM read and write support for JV880.

JV880 needs NVRAM file passed via --nvram.

Also the file where SRAM and NVRAM will be saved will have a suffix incidicating the corresponding emulator instance. Do note that the implementation of JV880 NVRAM has a bug

Regarding Buffer Size

Buffer size ontrols the amount of audio to produce or output at a time. Lower values reduce latency; higher values reduce playback glitches. Optimal settings are hardware dependent, so experiment with this option. If no value is provided, it will default to 512:16 roughly mirroring upstream's intent.

size is the number of audio frames that the emulator will produce and the output will consume in a single chunk. It must be a power of 2.

count is the number of size pages that can be queued up. It can be any value greater than zero, but the best value is likely in the range 2..32.

Having queued chunks is helpful if the emulator produces audio fast enough most of the time but sometimes falls behind. This can happen for music containing particularly busy sections. The queued chunks give the emulator some headroom so that even if it slows down temporarily, the output has enough audio to work with until the emulator catches back up.

Example

Consider -b 512:16: The SC-55mk2 outputs at 66207hz. The emulator would produce chunks of 512/66207 = 7.7ms of audio at a time. It would be allowed to queue up to 16 of those chunks, meaning that you could have up to 512*16/66207 = 123ms of latency.

Divergence from upstream

The behavior of this option was changed because the way upstream uses it is buggy and unintuitive.

Upstream defaults to -b 512:32. For this setting, it creates a ringbuffer of 512*32 samples, but the buffer only holds 512*16 frames (each frame consists of two samples, one for each stereo channel). The emulator will place one frame at a time into this buffer. Audio will be drained from the buffer for playback 512/4 = 128 frames at a time. The /4 is arbitrary and cannot be set by the user.

In theory, the buffer should be able to contain ~123ms of audio, but because upstream reads from the buffer unconditionally, the read position can overtake the write position causing dropped frames. This also causes a variable amount of latency, because at the start of the program the read position will start advancing - it then takes 123ms to get back to the start of the buffer where audio has started being written.

This fork since it depends on jcmoyer's fork also corrects the ringbuffer behavior - instead of advancing the read position unconditionally, it only advances when there is audio to play and produces silence otherwise. The buffer size you provide to this option is in frames instead of samples, and the numbers you provide are used without modification by both the emulator and output.

Regarding ASIO Sample Rate

When using --asio-sample-rate, if a sampling frequency is expected. If n value is provided, the emulator will request the native frequency from the the selected romset.

The emulator natively produces audio at 64000hz or 66207hz depending on the romset. Some ASIO drivers cannot support these frequencies so resampling to <rate> is necessary.

Advanced parameters

--override-* <path>

Overrides the path for a specific rom. This bypasses the default methods of locating roms.

Each romset consists of multiple roms that are individually loaded into different locations within the emulator. These rom locations are named:

  • rom1
  • rom2
  • smrom
  • waverom1
  • waverom2
  • waverom3
  • waverom-card
  • waverom-exp

A romset does not necessarily use all of these rom locations. For example, the mk2 will only use rom1, rom2, smrom, waverom1, and waverom2.

To override a specific rom path you can replace the * in --override-* <path> with the name of the rom location you would like to load instead, e.g. --override-rom2 ctf-patched-rom2.bin. This is useful in case you have a patched rom that the emulator does not recognize.