SF2000

The SF2000 is a cheap hand-held emulation gaming console which was released in early 2023. Although the device itself is sold by a variety of vendors, it was the vendor "Data Frog" who caught public attention, and so the device is often simply referred to as "the Data Frog".

For a cheap device, it's actually fairly capable - most Game Boy, Game Boy Color, NES and Genesis/Mega Drive games play at full speed, and many arcade, Game Boy Advance and SNES titles do as well. The device has an IPS panel (not OCA laminated), and a user-replacable "18650" battery, which can be charged via a USB-C port on the device. It also has analog A/V out (note: not HDMI), meaning it can be connected to a CRT TV - the type of display most arcade, Genesis/Mega Drive and SNES games were originally intended to be displayed on. It has a built-in 2.4GHz antenna, and can receive input from a compatible wireless controller (usually sold separately).

Some downsides to the device: it's mono-only, there's no head-phone jack (although there is a volume wheel), screen brightness cannot be altered (it's fairly bright), SNES and Game Boy Advance are hit-or-miss in terms of performance (some games are fine, many games run slowly), the stock firmware is closed-source so the device's performance may never get any better than as-shipped, and some folks have had issues with the buttons (they're quite cheap, and sit flush when pressed).

So is the "Data Frog" any good? Only you can answer that question for yourself. There are certainly more powerful devices out there, more fully featured devices, devices with better hardware, etc. - but almost all of those devices cost a lot more than the SF2000. At the end of the day, you have to look at the features offered at the given price-point, and only then can you decide if you're interested in the device or not.

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Hardware

Although the main CPU of the SF2000 has literally had it's markings milled off by a routing tool, the community has determined that it's a HCSEMI B210, a single-core MIPS processor running at 810 MHz. It appears to be a clone of an ALi Tech chip.

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biserv.asd

The firmware for the SF2000 is actually located on the microSD card, in a file called biserv.asd located in the BIOS folder. This file is a monolithic binary blob, which contains the device's OS, the emulators, their settings... basically everything. The file is currently being investigated. Here are some findings from it:

Key Bindings

osaka#9664 discovered that the OS supports loading game-specific key bindings from .kmp files, stored in the save folder for each system and named after a game's ROM file (e.g., /FC/save/Game Name.kmp). They also discovered where in the biserv.asd file the default mappings for each emulator are stored. Working with this information, notv37#4200 worked out what bits related to what buttons for each emulator. Using notv37#4200's findings, osaka#9664 has put together a web-based tool which can be used to alter the default key bindings for each emulator, as well as to create game-specific bindings - you can find that tool here.

Boot Logo

When the device is powered on, a "Welcome" image is displayed for a short time before the main menu appears. This image comes from inside biserv.asd, at offset 0x9B91D8. It's a 512x200 RGB565 Little Endian raw image file, and looks like this:

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Resources

The Resources folder on the microSD card contains all of the resources used by the device's firmware to construct the user interface at runtime. The following tables list the files from the 20230420 firmware and what they are used for, grouped by broad categories:

Fonts

Filename	Description
Arial_cn.ttf	The "Arial" typeface, containing Latin, Greek, Cyrillic, Chinese, and Japanese characters. Duplicate of yahei_Arial.ttf, the single font file from the original firmware version
Arial_en.ttf	The "Arial" typeface, containing Latin, Greek, Cyrillic, Armenian, Hebrew and Arabic characters
Arial_jp.ttf	The "Arial" typeface, containing Latin, Greek, Cyrillic, Chinese and Japanese characters
Arial_kr.ttf	The "Arial" typeface, containing Latin, Greek, Cyrillic, Chinese, Japanese and Korean characters
Tahoma.ttf	The "Tahoma" typeface, containing Latin, Greek, Cyrillic, Armenian, Hebrew, Arabic and Thai characters
yahei_Arial.ttf	The "Arial" typeface, containing Latin, Greek, Cyrillic, Chinese, Japanese and Korean characters

Images (Used)

As far as I am aware, all of the below images are actively used by the 20230420 version of the firmware; happy to take any corrections if it turns out any of them are unused! Note that while the stock theme is based around a 640x480 resolution, the actual //display// on the SF2000 is a 320x240 one. The OS on the device uses nearest-neighbour scaling for its images, giving the stock UI a somewhat aliased appearance. If you're planning to make your own theme for the SF2000, design it for 320x240, and then double the resolution when exporting the final images to the device for a crisper look.

Filename	Resolution	Format	Description	View
aepic.nec	576x256	BGRA	Main menu labels in Korean	view
apisa.dlk	640x480	RGB565 Little Endian	Arcade game list background	view
appvc.ikb	150x214	BRGA	Game art placeholder	view
awusa.tax	576x256	BRGA	Main menu labels in Thai	view
bisrv.nec	640x480	RGB565 Little Endian	In-game menu (position 3)	view
bttlve.kbp	60x144	BGRA	Battery level indicator icons	view
c1eac.pal	640x480	RGB565 Little Endian	SNES game-list background	view
cero.phl	640x480	RGB565 Little Endian	Game Boy Color game-list background	view
certlm.msa	40x24	BGRA	NES game-list indicator	view
d2d1.hgp	640x480	RGB565 Little Endian	In-game menu (position 2)	view
dism.csf	640x480	RGB565 Little Endian	In-game menu (position 1)	view
djctq.rsd	40x24	BGRA	SNES game-list indicator	view
djoin.nec	576x256	BRGA	Main menu labels in Spanish	view
dpskc.ctp	640x320	RGB565 Little Endian	In-game menu save-state slots (positions 1, 2, 3 and 4)	view
drivr.ers	640x480	RGB565 Little Endian	SNES main menu background	view
dsuei.cpl	640x480	RGB565 Little Endian	User ROMs main menu background	view
dxdiag.bin	40x24	BGRA	Genesis/Mega Drive game-list indicator	view
dxkgi.ctp	576x256	BRGA	Main menu labels in English	view
dxva2.nec	640x480	RGB565 Little Endian	Search keyboard (pressed)	view
ectte.bke	161x126	BRGA	Main menu icon selection box	view
efsui.stc	640x480	RGB565 Little Endian	Game Boy Advance game-list background	view
esent.bvs	576x256	BRGA	Main menu labels in Turkish	view
exaxz.hsp	152x1224	BRGA	Main menu "Games Exist" and "Start: Open" labels for all languages	view
fixas.ctp	640x480	RGB565 Little Endian	NES main menu background	view
fltmc.sta	640x480	RGB565 Little Endian	Game Boy game-list background	view
fvecpl.ai	40x24	BGRA	Game Boy game-list indicator	view
gpsvc.bvs	392x80	RGB565 Little Endian	In-game menu save-state slot (position 3)	view
hctml.ers	640x480	RGB565 Little Endian	Arcade main menu background	view
hgcpl.cke	392x80	RGB565 Little Endian	In-game menu save-state slot (position 2)	view
hlink.bvs	640x480	RGB565 Little Endian	Search keyboard (hover)	view
htui.kcc	40x24	BGRA	Game Boy Color game-list indicator	view
icm32.dll	40x24	BGRA	Game Boy Advance game-list indicator	view
icuin.cpl	640x480	RGB565 Little Endian	Genesis/Mega Drive main menu background	view
ihdsf.bke	640x480	RGB565 Little Endian	Genesis/Mega Drive game-list background	view
irftp.ctp	640x480	RGB565 Little Endian	Game Boy Advance main menu background	view
irmon.tax	576x256	BRGA	Main menu labels in Dutch	view
itiss.ers	576x256	BRGA	Main menu labels in Chinese	view
jccatm.kbp	640x480	RGB565 Little Endian	"Battery Empty" screen	view
ke89a.bvs	576x256	BRGA	Main menu labels in Portuguese	view
ksxbar.ax	392x80	RGB565 Little Endian	In-game menu save-state slot (position 4)	view
lfsvc.dll	640x480	RGB565 Little Endian	Search game-list background	view
mksh.rcv	640x480	RGB565 Little Endian	Search keyboard (normal)	view
msdmo.gdb	392x80	RGB565 Little Endian	In-game menu save-state slot (position 1)	view
msgsm.dll	40x24	BGRA	Arcade game-list indicator	view
mssvp.nec	576x256	BRGA	Main menu labels in Japanese	view
normidna.bin	40x24	BGRA	Search game-list indicator	view
ntdll.bvs	576x256	BRGA	Main menu labels in Polish	view
pcadm.nec	576x256	BRGA	Main menu labels in Italian	view
pwsso.occ	640x480	RGB565 Little Endian	In-game menu (position 4)	view
qasf.bel	640x480	RGB565 Little Endian	User game-list background	view
qwave.bke	640x480	RGB565 Little Endian	Game Boy Color main menu background	view
rmapi.tax	576x256	BRGA	Main menu labels in German	view
sdclt.occ	120x2280	RGB565 Little Endian	TV system and UI language selection icons	view
sebsc.bvs	576x256	BRGA	Main menu labels in French	view
sfcdr.cpl	576x1344	BRGA	Main menu system logos	view
subst.tax	576x256	BRGA	Main menu labels in Russian	view
ucby4.aax	576x256	BRGA	Main menu labels in Arabic	view
urlkp.bvs	640x480	RGB565 Little Endian	NES game-list background	view
vidca.bvs	576x256	BRGA	Main menu labels in Hebrew	view
vssvc.nec	576x256	BRGA	Main menu labels in Malay	view
xajkg.hsp	640x480	RGB565 Little Endian	Game Boy main menu background	view

Images (Unused)

To the best of my knowledge, the following image files are currently unused by the 20230420 firmware, and were probably left over from previous devices (the SF2000 shares a bit of lineage with some USB-stick devices) or development. The images marked "Alternate UI" below appear to have been for a UI where the systems were scrolled through horizontally, and the "shortcut" games for each system were scrolled vertically.

Filename	Resolution	Format	Description	View
aeinv.bke	640x480	RGB565 Little Endian	Alternate UI: Genesis/Mega Drive main menu background	view
aepic.ers	640x480	RGB565 Little Endian	Alternate UI: User main menu background	view
c1e.pal	640x480	RGB565 Little Endian	CPS2 game-list background	view
cca.bvs	640x480	RGB565 Little Endian	In-game menu (position 1; Chinese language hardcoded)	view
dectMap.key	640x480	RGB565 Little Endian	Button test screen (active)	view
desk.cpl	640x480	RGB565 Little Endian	Eight-game selection screen	view
djoin.hsp	640x480	RGB565 Little Endian	Alternate UI: Arcade main menu background	view
fcont.ctp	640x480	RGB565 Little Endian	Alternate UI: User main menu background	view
fdbil.ph	1100x120	BGRA	Large icons for each system, including systems not supported by the SF2000 (selected)	view
gpapi.bvs	640x480	RGB565 Little Endian	In-game menu (position 5; looks like it was for some kind of button layout changing UI)	view
igc64.dll	217x37	BGRA	"Yes" and "No" text, with "No" selected	view
ihds.bke	640x480	RGB565 Little Endian	Genesis/Mega Drive game-list background, with baked-in thumbnail placeholder	view
kdill.hsp	640x480	RGB565 Little Endian	Alternate UI: Game Boy Advance main menu background	view
logilda.be	40x24	BGRA	CPS1 game-list indicator	view
mfc64.emc	40x24	BGRA	CPS2 game-list indicator	view
mfpmp.ers	640x480	RGB565 Little Endian	Alternate UI: Arcade main menu background	view
mrtac.klo	40x24	BGRA	Neogeo game-list indicator	view
msdtc.bke	640x480	RGB565 Little Endian	Alternate UI: Game Boy Advance main menu background	view
mswbv.cpl	640x480	RGB565 Little Endian	Alternate UI: Game Boy Advance main menu background	view
nettrace.dll	40x24	BGRA	Unknown game-list indicator (grey joystick with yellow buttons)	view
nsibm.ctp	640x480	RGB565 Little Endian	Alternate UI: Arcade main menu background	view
nvinf.hsp	16x240	BGRA	Latin numbers 0 to 9 listed vertically	view
nvinfohsp	640x480	RGB565 Little Endian	Alternate UI: Genesis/Mega Drive main menu background (note: there's no extension separator for this file, I suspect the file name is typo'd in the filesystem!)	view
pcadm.hsp	640x480	RGB565 Little Endian	Alternate UI: User main menu background (NTSC TV system selected)	view
plasy.ers	640x480	RGB565 Little Endian	Alternate UI: Game Boy Advance main menu background	view
rmapi.cpl	640x480	RGB565 Little Endian	Alternate UI: User main menu background (English UI language selected)	view
seltMap.key	640x480	RGB565 Little Endian	Button test screen	view
spmpm.gdp	640x480	RGB565 Little Endian	Alternate UI: NES game-list background, with baked-in thumbnail placeholder	view
subst.bke	640x480	RGB565 Little Endian	Alternate UI: Arcade main menu background	view
tsmcf.cpl	640x480	RGB565 Little Endian	Alternate UI: Arcade main menu background	view
url.bvs	640x480	RGB565 Little Endian	CPS1 game-list background	view
werui.ioc	320x240	RGB565 Little Endian	"NODATA" save-state thumbnail placeholder image, with a "horror" style typeface	view
wshom.ocx	1100x120	BGRA	Large icons for each system, including systems not supported by the SF2000 (normal)	view
wshrm.nec	217x37	BGRA	"Yes" and "No" text, with "Yes" selected	view
x86e.hgp	640x480	RGB565 Little Endian	Neogeo game-list background	view

Other Files

These are other files that have been identified, which don't fit into the other categories. Non-Latin characters in the files are encoded in UTF-8.

Filename	Description
bfrjd.odb	UI strings in Korean
bxvtb.sby	UI strings in Thai
dufdr.cwr	UI strings in Turkish
eknjo.ofd	UI strings in Spanish
fhshl.skb	UI strings in English
Foldername.ini	Used to control menu rotation for the main menu (this information came from the 4PDA forum)
jsnno.uby	UI strings in Dutch
kcbn7.avc	Duplicate copy of bisrv.asd, the main firmware for the device which is found in the BIOS folder
lf9lb.cut	UI strings in Portuguese
ntrcq.oba	UI strings in Japanese
ouenj.dut	UI strings in Polish
qdbec.ofd	UI strings in Italian
sgotd.cwt	UI strings in French
snbqj.uby	UI strings in German
t2act.sgf	UI strings in Chinese
Test.zsf	A SNES ROM, which displays a controller test program
tvctu.uby	UI strings in Russian
vdaz5.bjk	UI strings in Arabic
wtrxj.lbd	UI strings in Malay
xjebd.clq	UI strings in Hebrew

ROM Lists

Credit for this section goes to taizou#9644, author of Frog Tool. These files relate to the built-in game lists under each main system; the list of games is pulled from these files instead of being built at runtime - annoying, but presumably for performance reasons. It means if you want to change the list of built-in games (instead of using the User ROMs section), you have to edit these files - hence Frog Tool, you should really check it out.

Files	Description
mfpmp.bvs (Arcade), mgdel.bvs (Game Boy Color), nethn.bvs (NES), qdvd6.bvs (Game Boy), sppnp.bvs (Game Boy Advance), wmiui.bvs (Genesis/Mega Drive), xvb6c.bvs (SNES)	Pinyin translations of the English ROM names, used for Chinese language searching. Not all game names are translated
adsnt.nec (SNES), fhcfg.nec (NES), htuiw.nec (Game Boy Advance), msdtc.nec (Arcade), setxa.nec (Genesis/Mega Drive), umboa.nec (Game Boy), wjere.nec (Game Boy Color)	Chinese translations of the English ROM names, used to display the game lists when the UI language is set to Chinese. Not all game names are translated
mswb7.tax (Arcade), pnpui.tax (Game Boy Color), rdbui.tax (NES), scksp.tax (Genesis/Mega Drive), urefs.tax (SNES), vdsdc.tax (Game Boy), vfnet.tax (Game Boy Advance)	English ROM Names, used to display the game lists when the UI language is set to English
xfgle.hgp, xfgle.hgp.bak	The xfgle.hgp file contains the ROM "shortcuts" on the main menu for each game system. The xfgle.hgp.bak file appears to be a test version of this file that was not removed from the firmware before being sent to production
TSMFK.TAX	This is a ROM list file similar to the other .tax files, except it is built at run-time from the ROM files in the user roms folder. The file is regenerated each time the device boots

Sounds

There are several sound files in the 20230420 firmware, stored in raw signed 16-bit PCM format (mono, little-endian at 22050 Hz). The SF2000 seems to play the files back at an incorrect sample rate vs. the raw data; if you want to customise the background music, resample your audio to 21543 Hz, and then speed the audio up to 22050 Hz, using the resulting audio as the raw data (credit to notv37#4200 in Discord for doing the math on that).

Filename	Description	Listen
c2fkec.pgt	"Popping" sound that is played when moving around the search keyboard	listen
dpnet.dll	"Downwards Zap" sound, unknown usage	listen
dsreg.bvs	"Upwards Bleeping" sound, unknown usage	listen
help.lis	"Double Buzzer" sound, unknown usage	listen
mfsvr.nkf	"Beep" sound that is played when entering a letter on the search keyboard	listen
nyquest.gdb	"Whooshing" sound that is played when switching between emulated systems on the main menu, between the "Resume", "Quit", "Load" and "Save" options on the in-game menu, and scrolling by pages within a system's game-list	listen
oldversion.kbe	"Three Note Upward Chime" sound that is played when deleting a letter on the search keyboard	listen
pagefile.sys	Main menu background music	listen
swapfile.sys	"Squishy" sound played when navigating horizontally through "shortcut" games on the main menu, or vertically within a system's game-list	listen

Unknown Files

These are files that I have not yet determined what they do; if anyone has any information on these, do post about it in the Data Frog channel in the Retro Handhelds Discord server please!

Filename	Description
Archive.sys	UNKNOWN; 8 bytes, first are 0x02, the rest are all 0x00
kcnuv.lit	UNKNOWN; a bunch of 4-byte binary chunks (e.g., 0xC4 0x00 0x00 0x00), followed by a list of .NES ROM file names. Very similar to the .bvs/.nec/.tax files detailed above, but doesn't have the same type of "header" they have

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Version History

20230507 - 1.1: Some "unknown" files from the Resources folder identified with taizou#9644's help (thanks!); moved them to the Sounds and Rom Lists sections with details. Only two files left!

20230507 - 1.0: Original creation of this page.