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 included below.
- -h, --help
- print help and exit
- -a, --autoframeskip
- 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_idle
- 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.
- --color_filter
- turn on the color filter.
- -r, --rumble
- turn on the rumble simulation. This will cause the emulated screen to
shake when a rumble effect is caused by the running program.
- --filter=X
- 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
- -R, --res=WxH
- set the screen resolution to WxH (for YUV and GL mode only).
- -Y, --yuv
- 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 excellent performance.
- --yuv_type
- set the type of the YUV overlay: 0 = YV12 1 = YUY2
- -o, --opengl
- 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 support.
- -f, --fullscreen
- run gngb in fullscreen. Fullscreen can be toggled during use with F9.
- --fps
- Show frames per second counter in the upper left corner of screen. May be
toggled through the emulator's menu.
- -s, --sound
- Enable sound.
- --sample_rate=RATE
- Set the sound output sample rate to RATE. (typically a multiple of 11025
Hz)
- --auto_gb
- 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.
- -j, --joy_dev=N
- The default joystick is /dev/js0. By setting N here, /dev/jsN will be used
in its place.
- -g, --gdma_cycle
- This experimental option will halt the CPU during certain DMA operations.
Leave it off unless you are working around problems in a certain
program.
- -v, --version
- Show version of program.
Most options can be disabled whith --no-OPTION (Ex: --no-sound
turn sound off)
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 <nemesis@dbz.icequake.net>, for the
Debian GNU/Linux system (but may be used by others).