gngb - emulate various Nintendo Game Boy handheld systems
gngb [-h] | [options] <romname>
gngb is an emulator program that attempts to be various forms of
Nintendo Game Boy hardware. It can run the various homebrew games and
demos for the system as well as images of commercially-released games.
This manual page was written for the Debian GNU/Linux distribution
because the original program does not have a manual page.
The program follows the usual GNU command line syntax, with long
options starting with two dashes (‘-’). A summary of options are
print help and exit
turn on autoframeskip. This is useful if the emulator is
running too slow. It will cause the emulator to drop frames
every now and then to maintain a realtime emulation.
sleep when idle. This will cause the program to sleep when it
has idle cycles instead of busy looping. However, this can
degrade emulation performance under some circumstances.
turn on the color filter.
turn on the rumble simulation. This will cause the emulated
screen to shake when a rumble effect is caused by the running
Set the filter to apply. These only work when using standard
(not YUV or GL) video output. 0 = none 1 = scanline 2 =
scanline 50% 3 = smooth 4 = pseudo cell shading
set the screen resolution to WxH (for YUV and GL mode only).
turn YUV mode on. This utilizes the hardware YUV colorspace
conversion and scaling features if your video card supports it.
Most video cards with Xv support can use this feature for
set the type of the YUV overlay: 0 = YV12 1 = YUY2
turn OpenGL mode on. This will render the gameboy screen as an
OpenGL 3D texture, which on some cards may perform much better
than the YUV or X11 output. This requires a 3D card with GLX
run gngb in fullscreen. Fullscreen can be toggled during use
--fps Show frames per second counter in the upper left corner of
screen. May be toggled through the emulator’s menu.
Set the sound output sample rate to RATE. (typically a multiple
of 11025 Hz)
Automatically detect the system to emulate based on the
cartridge image that is selected. This should work in most
cases. If it fails, you can use one of the [ -C, --color_gb |
-G, --normal_gb | -S, --super_gb ] options to force emulation of
a Color, Normal, or Super Game Boy.
The default joystick is /dev/js0. By setting N here, /dev/jsN
will be used in its place.
This experimental option will halt the CPU during certain DMA
operations. Leave it off unless you are working around problems
in a certain program.
Show version of program.
Most options can be disabled whith --no-OPTION (Ex: --no-sound turn
These are the default keys in the emulator. These, along with the
joystick buttons, may be changed through a custom gngbrc(5) file.
Enter : Start
Right Shift : Select
W : B
X : A
TAB : Open menu
F9 : fullscreen on/off
F10 : show fps
F11 : reset
F12 : show keysym code
KeyPad 1-5: Change palette
Palette must be define in your gngbrc file (see sample_gngbrc)
KeyPad 6 : Toggle color filter
There is some good info in the README included in the doc directory.
The gngbrc file is documented in manual section 5.
This manual page was written by RCU <firstname.lastname@example.org>, for the
Debian GNU/Linux system (but may be used by others).