NINTENDO(1) NINTENDO(1)
NAME
gb, gba, nes, snes - emulators
SYNOPSIS
games/gb [ -acd ] [ -C ... ] [ -x scale ] [ -li addr ]
romfile
games/gba [ -a ] [ -b biosfile ] [ -s savetype ] [ -g
gpiotype ] [ -x scale ] romfile
games/nes [ -aos ] [ -x scale ] romfile
games/snes [ -ahms ] [ -x scale ] romfile
DESCRIPTION
Gb, gba, nes and snes are emulators for the Nintendo Game
Boy and Game Boy Color (GB and GBC), Nintendo Game Boy
Advance (GBA), Nintendo Entertainment System (NES), and
Super Nintendo Entertainment System (SNES). They execute
the romfile given as an argument. The z, x, a, s, q, w,
return and shift keys correspond to B, A, Y, X, L1, L2,
Start and Select, respectively. Other keys:
F1 Pause the emulator. If already paused it will step one
video frame.
F5 Save the current state in gb.save / gba.save / nes.save
/ snes.save.
F6 Load the current state from gb.save / gba.save /
nes.save / snes.save.
F12 Toggle the emulator's speedometer. It shows in the
upper left, off-viewport corner, the ratio between the
expected and observed time it took to draw 60 frames.
t Toggle tracing of the emulator.
` It uncaps the 60fps frame rate and lets emulation go as
fast as possible.
Esc Pause the emulator.
Del Exit the emulator.
Command line options:
-a Enable audio output.
-x Scale the screen to a given factor regardless of the
window's size.
gb options:
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NINTENDO(1) NINTENDO(1)
-c Run GBC roms in GBC mode and DMG (GB) roms in GBC's DMG
compatibility mode.
-d Run GB roms in DMG mode. GBC-only roms will not run in
this mode; others will run only in black & white.
-Cnnnnnn,nnnnnn,nnnnnn,nnnnnn
Select a color palette. Has no effect on roms in color
mode. The syntax is of the form -C
ffffff,aaaaaa,555555,000000 (using HTML style rrggbb
notation).
-liaddr
These enable serial port connectivity emulation using
the network. The -l flag configures the listening part-
ner, whereas -i configures the dialing partner. The
connection is established before the rom starts. Com-
munication is synchronous, emulation will stall while
waiting for the other partner.
gba options:
-b Location of the GBA BIOS file (required to operate the
emulator). Default is /sys/games/lib/gbabios.bin.
-s Save format used by the original game. Valid formats
are: eeprom4, eeprom64, sram256, flash512, flash1024.
The number corresponds to the size, in kilobits, of the
save file. By default, the emulator attempts to auto-
matically detect the save format, but does not always
succeed. Some roms require a specific flash device id
which may need to be set manually for them to work.
Valid formats and corresponding ids are: flash512
(SST), flash512mx (Macronix 64K), flash512pan (Pana-
sonic), flash512atm (Atmel), flash1024 (Macronix 128K),
flash1024san (Sanyo).
-g GPIO hardware used by the original game. The only valid
type currently is rtc (real time clock). By default,
the emulator attempts to automatically detect the GPIO
hardware using the game code found in the rom header.
nes options:
-o Hide the top and bottom eight pixels (overscan area),
like a real television would.
-s Save contents of battery backed SRAM (used by some
games for savegames) as a file (gb and snes automati-
cally detect if this is needed).
snes options:
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NINTENDO(1) NINTENDO(1)
-h Override HiROM/LoROM detection: -h sets LoROM, -hh sets
HiROM.
-m Enable mouse emulation using system mouse. Mouse button
1 (left button) engages the SNES left mouse button.
Mouse button 3 (right button) engages the SNES right
mouse button. Holding down mouse button 2 (middle but-
ton) disengages the SNES mouse entirely so that the
Plan 9 cursor offset can be adjusted to align with the
SNES cursor.
Each of these emulators support the use of joysticks via
joy(1). Nes also supports selecting the joystick for either
player 1 or 2.
SOURCE
/sys/src/games/gb
/sys/src/games/gba
/sys/src/games/nes
/sys/src/games/snes
BUGS
You bet!
SRAM saving on the NES only functions when the -s option is
used.
The SNES horizontal hires mode is supported only with -2
scaling.
All emulators assume a North American (i.e. NTSC) system.
PAL games (and in some cases Japanese games) are not sup-
ported.
The serial link emulation has issues with desynchronization
in timing dependent scenarios.
HISTORY
Gb first appeared in 9front (April, 2012).
Gba first appeared in 9front (September, 2014).
Nes first appeared in 9front (February, 2014).
Snes first appeared in 9front (March, 2014).
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