General updates

Updated date in the custom firmware FAQ. Corrected some image paths. Identified the usage of `mhg4s.ihg`, `zaqrc.olc` and `help.lis` resources files (thanks to `nummacway` for the hint!).

README.md

@@ -77,13 +77,13 @@ Some downsides to the device: There's a decent amount of screen-tearing, due to
 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 (which often sells for just $15 to $20). 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.
 
 ### Is there any custom firmware?
-As of April 1st 2024, **no**, not yet; however, some already-useful advancements have been made which may be of interest. Two main development efforts have been made:
+As of April 29st 2024, **no**, not yet; however, some already-useful advancements have been made which may be of interest. Two main development efforts have been made:
 
 #### hcRTOS (true CFW)
 Earlier this year, an SDK for the CPU in the SF2000 was been identified. Theoretically, this would allow a full custom firmware to be built and compiled for the device. The developers working on custom firmware spent some considerable time and effort working on porting Retroarch (as it seemed like it would be the quickest route to a custom firmware with support for many systems), however they ran into several problems. It appears that the SDK was unfinished and of low quality - core features like video and audio drivers were missing (and thus had to be developed from scratch), and overall system stability of the produced builds very low. When crashed happened with running cores (which was frequently) no useful debugging information was produced, and so tracking down the source of issues became a major time-sink. Additionally, most of the experimental builds when they did work had audio and/or video performance issues, and most also caused the SF2000 to run "hot", which would likely have impacted the lifespan of the device and thus are not recommended for usage beyond a few minutes at a time. [A GitLab repo](https://git.maschath.de/ignatz/hcrtos) was set up by `ignatzdraconis` for the work based on this SDK, however work on developing a full custom firmware using this SDK has been parked for now.
 
 #### Multicore (modified stock)
-More recently, a new tack is being tried by the development team - they're trying to modify the stock SF2000 firmware to add additional functionality. Theoretically, this would come with the benefit of having audio and video drivers already built (the contractors producing the stock firmware for the SF2000 have access to these), providing no worse performance than stock firmware, while also providing features like support for additional emulated systems. An experimental developer build called the "multicore" build has been produced which hijacks the stock Game Boy Advance emulator to run additional systems like Atari 2600, PC-Engine, MAME2000, Sega 32X, etc., and some stand-alone engines for games like Doom and Cave Story, as well as alternatives for some of the stock emulators already included with the SF2000 (e.g., a more recent build of gpSP, Snes9x 2005 and 2002, etc.). Some of the new systems appear to run at full speed; some run without sound or with less than full speed, and others don't work at all yet. [A GitLab repo](https://gitlab.com/kobily/sf2000_multicore) has been set up by `kobil` for the work on modifying the stock firmware; additionally, [a GitHub repo](https://github.com/madcock/sf2000_multicore_cores) has been set up by `adcockm` for the code changes for the individual cores, and you can download the **experimental** alpha build [from the "Releases" page there](https://github.com/madcock/sf2000_multicore_cores/releases/latest). If you want to follow along with the developer chat on this work, see the `SF2000 Dev` thread in the `🐸data_frog_sf2000` channel of the [`Retro Handhelds` Discord server](https://discord.gg/retrohandhelds). Please do read the pinned messages both in the main channel and the thread before asking any questions of the devs, their time is precious 🙂
+More recently, a new tack is being tried by the development team - they're trying to modify the stock SF2000 firmware to add additional functionality. Theoretically, this would come with the benefit of having audio and video drivers already built (the contractors producing the stock firmware for the SF2000 have access to these), providing no worse performance than stock firmware, while also providing features like support for additional emulated systems. An experimental developer build called the "multicore" build has been produced which hijacks the stock Game Boy Advance emulator to run additional systems like Atari 2600, PC-Engine, MAME2000, Sega 32X, etc., and some stand-alone engines for games like Doom and Cave Story, as well as alternatives for some of the stock emulators already included with the SF2000 (e.g., a build of gpSP with working dynarec, Snes9x 2005 and 2002, etc.). Some of the new systems appear to run at full speed; some run without sound or with less than full speed, and others don't work at all yet. [A GitLab repo](https://gitlab.com/kobily/sf2000_multicore) has been set up by `kobil` for the work on modifying the stock firmware; additionally, [a GitHub repo](https://github.com/madcock/sf2000_multicore_cores) has been set up by `adcockm` for the code changes for the individual cores, and you can download the **experimental** alpha build [from the "Releases" page there](https://github.com/madcock/sf2000_multicore_cores/releases/latest). If you want to follow along with the developer chat on this work, see the `SF2000 Dev` thread in the `🐸data_frog_sf2000` channel of the [`Retro Handhelds` Discord server](https://discord.gg/retrohandhelds). Please do read the pinned messages both in the main channel and the thread before asking any questions of the devs, their time is precious 🙂
 
 ### I just got my SF2000; what modding can I do with it?
 If you're planning to customise your SF2000 in _any_ way, then I **strongly** recommend the _very_ first thing you do is [fix an annoying bug in the device's bootloader](#bootloader-bug) - otherwise you're likely to end up with a non-booting device. Seriously - **do this before you do anything else!**
@@ -433,6 +433,7 @@ As far as I am aware, all of the below images are actively used by the latest fi
 | `lfsvc.dll` | 640x480 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | Search game-list background | [view](/images/lfsvc.png) |
 | `lk7tc.bvs` | 52x192 | BGRA |  |  | ✨ | ✅ | ✅ | ✅ | ✅ | Transparent labels for the button assignments in the new button mapping feature; these are the ones overlaid on the big SF2000 image showing the current assignments | [view](/images/lk7tc.bvs.png) |
 | `lkvax.aef` | 640x480 | RGB565 Little Endian |  |  | ✨ | ✅ | ✅ | ✅ | ✅ | History game-list background | [view](/images/lkvax.aef.png) |
+| `mhg4s.ihg` | 400x192 | RGB565 Little Endian |  |  | ✨ | ✅ | ✅ | ✅ | ✅ | Background and buttons for a "warning" prompt with "OK", "Yes" and "No" buttons, used when asking the user if they want to remove an item from favourites, when the favourites list is full, etc.. Also has rounded edges stored in a separate image file, `zaqrc.olc` | [view](/images/mhg4s.ihg.png) |
 | `mkhbc.rcv` | 640x1440 | RGB565 Little Endian |  |  | ✨ | ✅ | ✅ | ✅ | ✅ | Six vertically-stacked images of the SF2000 with different buttons highlighted, used as part of the new button mapping feature's UI | [view](/images/mkhbc.rcv.png) |
 | `mksh.rcv` | 640x480 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | Search keyboard (normal) | [view](/images/mksh.png) |
 | `msgsm.dll` | 40x24 | BGRA | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | Arcade game-list indicator | [view](/images/msgsm.png) |
@@ -457,6 +458,7 @@ As far as I am aware, all of the below images are actively used by the latest fi
 | `vssvc.nec` | 1008x164 | BRGA |  | ✨ | 🚩 | ✅ | ✅ | ✅ | ✅ | User settings screen icons and labels in Malay | [view](/images/vssvc.nec.png) |
 | `wshrm.nec` | 217x37 | BGRA | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | "Yes" and "No" text, with "Yes" selected; used when being asked if you want to overwrite a save-game slot | [view](/images/wshrm.png) |
 | `xajkg.hsp` | 640x480 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | Game Boy main menu background | [view](/images/xajkg.png) |
+| `zaqrc.olc` | 8x224 | BGRA |  |  | ✨ | ✅ | ✅ | ✅ | ✅ | Rounded ends that pair with the warning dialogue stored in `mhg4s.ihg` | [view](/images/zaqrc.olc.png) |
 | `ztrba.nec` | 64x320 | RGB565 Little Endian |  |  | ✨ | ✅ | ✅ | ✅ | ✅ | Non-transparent labels for the button assignments in the new button mapping feature; these are the ones that pop up when you go to change a button assignment | [view](/images/ztrba.nec.png) |
 
 ### Images (Unused)
@@ -474,17 +476,16 @@ To the best of my knowledge, the following image files are currently __unused__
 | `fcont.ctp` | 640x480 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | Alternate UI: User main menu background | [view](/images/unused/fcont.ctp.png) |
 | `fdbil.ph` | 1100x120 | BGRA | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | Large icons for each system, including systems not supported by the SF2000 (selected) | [view](/images/unused/fdbil.ph.png) |
 | `gpapi.bvs` | 640x480 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | In-game menu (position 5; looks like it was for some kind of button layout changing UI) | [view](/images/unused/gpapi.bvs.png) |
-| `gpsvc.bvs` | 392x80 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | In-game menu save-state slot (position 3) | [view](/images/gpsvc.png) |
-| `hgcpl.cke` | 392x80 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | In-game menu save-state slot (position 2) | [view](/images/hgcpl.png) |
+| `gpsvc.bvs` | 392x80 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | In-game menu save-state slot (position 3) | [view](/images/unused/gpsvc.png) |
+| `hgcpl.cke` | 392x80 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | In-game menu save-state slot (position 2) | [view](/images/unused/hgcpl.png) |
 | `ihds.bke` | 640x480 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | Genesis/Mega Drive game-list background, with baked-in thumbnail placeholder | [view](/images/unused/ihds.bke.png) |
 | `kdill.hsp` | 640x480 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | Alternate UI: Game Boy Advance main menu background | [view](/images/unused/kdill.hsp.png) |
-| `ksxbar.ax` | 392x80 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | In-game menu save-state slot (position 4) | [view](/images/ksxbar.png) |
+| `ksxbar.ax` | 392x80 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | In-game menu save-state slot (position 4) | [view](/images/unused/ksxbar.png) |
 | `logilda.be` | 40x24 | BGRA | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | CPS1 game-list indicator | [view](/images/unused/logilda.be.png) |
 | `mfc64.emc` | 40x24 | BGRA | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | CPS2 game-list indicator | [view](/images/unused/mfc64.emc.png) |
 | `mfpmp.ers` | 640x480 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | Alternate UI: Arcade main menu background | [view](/images/unused/mfpmp.ers.png) |
-| `mhg4s.ihg` | 400x192 | RGB565 Little Endian |  |  | ✨ | ✅ | ✅ | ✅ | ✅ | Background and buttons for a "warning" prompt with "OK", "Yes" and "No" buttons. Also has rounded edges stored in a separate image file, `zaqrc.olc` | [view](/images/unused/mhg4s.ihg.png) |
 | `mrtac.klo` | 40x24 | BGRA | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | Neo Geo game-list indicator | [view](/images/unused/mrtac.klo.png) |
-| `msdmo.gdb` | 392x80 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | In-game menu save-state slot (position 1) | [view](/images/msdmo.png) |
+| `msdmo.gdb` | 392x80 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | In-game menu save-state slot (position 1) | [view](/images/unused/msdmo.png) |
 | `msdtc.bke` | 640x480 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | Alternate UI: Game Boy Advance main menu background | [view](/images/unused/msdtc.bke.png) |
 | `mswbv.cpl` | 640x480 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | Alternate UI: Game Boy Advance main menu background | [view](/images/unused/mswbv.cpl.png) |
 | `nettrace.dll` | 40x24 | BGRA | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | Unknown game-list indicator (grey joystick with yellow buttons) | [view](/images/unused/nettrace.dll.png) |
@@ -501,7 +502,6 @@ To the best of my knowledge, the following image files are currently __unused__
 | `werui.ioc` | 320x240 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | "NODATA" save-state thumbnail placeholder image, with a "horror" style typeface | [view](/images/unused/werui.ioc.png) |
 | `wshom.ocx` | 1100x120 | BGRA | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | Large icons for each system, including systems not supported by the SF2000 (normal) | [view](/images/unused/wshom.ocx.png) |
 | `x86e.hgp` | 640x480 | RGB565 Little Endian | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | Neo Geo game-list background | [view](/images/unused/x86e.hgp.png) |
-| `zaqrc.olc` | 8x224 | BGRA |  |  | ✨ | ✅ | ✅ | ✅ | ✅ | Rounded ends that pair with the warning dialogue stored in `mhg4s.ihg` | [view](/images/zaqrc.olc.png) |
 
 ### 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.
@@ -633,7 +633,7 @@ If you want to do it using [Audacity](https://www.audacityteam.org/), the steps
 | `c2fkec.pgt` | ✨ | ✅ | 🚩 | ✅ | ✅ | ✅ | ✅ | "Popping" sound that is played when moving around the search keyboard | [listen](/sounds/c2fkec.pgt.mp3) |
 | `dpnet.dll` | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | "Downwards Zap" sound, unknown usage | [listen](/sounds/dpnet.dll.mp3) |
 | `dsreg.bvs` | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | "Upwards Bleeping" sound, unknown usage | [listen](/sounds/dsreg.bvs.mp3) |
-| `help.lis` | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | "Double Buzzer" sound, unknown usage | [listen](/sounds/help.lis.mp3) |
+| `help.lis` | ✨ | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | "Double Buzzer" sound, used when displaying the "Remove from favorites?" pop-up dialogue | [listen](/sounds/help.lis.mp3) |
 | `mfsvr.nkf` | ✨ | ✅ | 🚩 | ✅ | ✅ | ✅ | ✅ | "Beep" sound that is played when entering a letter on the search keyboard | [listen](/sounds/mfsvr.nkf.mp3) |
 | `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](/sounds/nyquest.gdb.mp3) |
 | `oldversion.kbe` | ✨ | ✅ | 🚩 | ✅ | ✅ | ✅ | ✅ | "Three Note Upward Chime" sound that is played when deleting a letter on the search keyboard | [listen](/sounds/oldversion.kbe.mp3) |
@@ -695,6 +695,8 @@ All of these are linked above already in their relevant sections, but just in ca
 ---
 
 ## Document Version History
+- `20240429 - 1.49`: Updated date in [the custom firmware FAQ](#is-there-any-custom-firmware). Corrected some image paths. Identified the usage of `mhg4s.ihg`, `zaqrc.olc` and `help.lis` resources files (thanks to `nummacway` for the hint!).
+
 - `20240401 - 1.48`: Updated date in [the custom firmware FAQ](#is-there-any-custom-firmware). Added links to `nummacway`'s GB300 info page. Added links to `GrGadam`'s SF2000 info page. Added links to `Dteyn`'s ROM-free SF2000 firmware downloads.
 
 - `20240223 - 1.47`: Updated [the CFW FAQ](#is-there-any-custom-firmware) with a more recent date. Added a basic FAQ answer about the [GB300](#whats-the-gb300). Added links to `.ericgoldstein`'s SF2000 setup guide. Now hosting the bootloader bugfix file directly, as Discord no longer allow hotlinking to files stored on their platform. Added a link to `Dteyn`'s SF2000 projects page. Added a link to `Dteyn`'s GB300 boot logo changer tool. Added a link to `johnnyonno`'s SF2000Renamers tool. Added a note to [the Save State Tool](https://vonmillhausen.github.io/sf2000/tools/saveStateTool.htm) to indicate that save states created on the SF2000 will likely only ever work with MIPS devices.