Tuesday, October 17, 2017

The Analogue Super Nt - The Day After Preview


If 2016 was the Year of the HDMI NES, with the release or pre-order availability of high quality NES HDMI devices such as the NES Classic Mini, Analogue Nt Mini and the RetroUSB AVS, then 2017 is the Year of the HDMI SNES, with the release of the SNES Classic Mini and now pre-order availability of the Analogue Super Nt.  The Super Nt was announced yesterday and I would like to gather all the available information about it here after 24 hours have passed to allow for information from multiple sources to be made available online.




The Super Nt is the next generation in Analogue's FPGA consoles.  The Nt Mini was released last year to great acclaim but a very high price tag ($449.00).  Officially it recreates the NES at a low logic level with FPGA technology and can output in 1080p HDMI and works with original cartridges.  The Super Nt recreates the SNES with a more powerful FPGA and can output in 1080p HDMI and works with original cartridges.

The designer of the Super Nt, like the Nt Mini, is Kevin Horton (kevtris).  Kevtris, developed his first FPGA core, for the NES, over a decade ago and has recreated cores for other video game systems like the ColecoVision, Arari 2600 & 7800, the Sega Master System and Game Gear and the Game Boy.  Prior to designing the hardware for the Nt Mini, kevtris developed and released the Hi-Def NES mod, a sophisticated FPGA-based upgrade to allow a stock NES or AV Famicom the ability to display in 1080p HDMI.  He also developed the HDMI upgrade for the original Analogue Nt, which saved Analogue's reputation because it had promised an HDMI upgrade in its kickstarter but had serious difficulties delivering on the HDMI upgrade until kevtris released his Hi-Def NES mod.

Kevtris' SNES core will be a highly accurate one.  I'm talking about bsnes/Higan level of accuracy, not SNES9x level of accuracy (which is the SNES Classic Mini's analogous level of compatibility).  He spent fourteen months recreating the SNES in an FPGA, running countless tests.  The CPU, the PPU1 & PPU2 and the APU all had to be recreated.  He built development boards that allowed him to run RGB from the original SNES and HDMI video from his FPGA side by side to identify flaws and bugs in his implementation.  Ironically, while he was secretly designing his board, there were two other individuals who were publicly designing FPGA SNES's independently of him.  He had previously made an SPC player to play music ripped from SNES games, but for this product his tools required him to fix bugs in his earlier work for the Super Nt.  He even managed to get "holy grail" behavior used by games like Speedy Gonzales: Los Gatos Bandidos working :  https://mgba.io/2017/07/31/holy-grail-bugs-2/


Certain vintage consoles can be modded to output in 1080p, and somewhat ironically they tend to be the ones with the fewest options for high quality analog video.  The Atari 2600 (theoretically), the NES (Hi-Def NES Mod), the Turbo Grafx 16 (UperGrafx), the N64 (UltraHDMI) and the GameCube (in development) all have or could have HDMI mods because their video chips send enough information digitally outside the chips to reconstruct the picture signal.  Other consoles like Sega Master System, Sega Genesis and Super Nintendo can output analog RGB without a mod but do not really have enough digital information available externally to reconstruct the video signal easily.  In order to get HDMI out of those consoles, you need an analog to HDMI converter, preferably the Open Source Scan Converter or the Framemeister.  Otherwise you would have to virtually recreate the video processing units of these systems and find a way to hack them into the console, not an easy mod.

Analogue's solution, the Super Nt, fulfills the demand for a true HDMI solution for the SNES.  Unlike the SNES Classic Mini, which is limited to 720p, the Super Nt can output in 1080p.  This reduces latency from any upconverting on a 1080p display.  The Super Nt can also output in 480p and 720p.  There are HD CRTs that will support 480p and 720p, so if they have an HDMI connector or you use an HDMI to component converter, the Super Nt may look very good on a CRT.  Finally, the Super Nt supports 60Hz and 50Hz modes, so any PAL exclusive games that have difficulty at 60Hz should work correctly.  However, the Super Nt has no ability to output analog video, no RF, no composite, no S-Video, no component video and no RGB.



Compared to the Nt Mini, the lack of analog video is a drawback.  The Super Nt is using a fully plastic enclosure instead of an mostly-aluminum enclosure.  The Super Nt only has two controller ports compared to the four ports of the Nt Mini.  The Super Nt only has one cartridge slot compared to the two of the Nt Mini and no expansion port for more esoteric controllers.  The Super Nt does not come with a bundled controller.  The result is a console that is simpler to design and much, much more affordable at $189.00.

The lack of analog video presents two issues.  First is that this console is incompatible with the light guns for the Super Nintendo, the Super Scope and the Konami Justifier.

There are six (6) Super Scope-only games

Battle Clash
Bazooka Blitzkrieg
Metal Combat: Falcon's Revenge
Super NES Super Scope 6
X-Zone
Yoshi's Safari

There are five (5) Super Scope optional games :

The Hunt for Red October
Lamborghini: American Challenge
Operation Thunderbolt
Terminator 2: Judgment Day
Tin Star

And one (1) Konami Justifier game :

Lethal Enforcers

The Super Nt does not have an expansion port on anywhere on the console, unless the original large SNES and Super Famicom.  The only known devices to use the SNES expansion port were the Japanese-only Broadcast Satellaview and the US-only Extertainment Life Fitness Exercise Bike.  The Satellaview service stopped broadcasting in June of 2000 (software downloaded onto a Memory Pak is still usable) and the Extertainment Bike is an insanely rare peripheral.

The other issue with a lack of analog video is that this console runs at a true 60fps rather than the 60.0988fps of an analog capable SNES.  Kevtris and Analogue specified this speed to ensure that the Super Nt is compatible with every HDMI TV.  The Open Source Scan Converter will send 60.0988fps to the TV, but some TVs simply will not accept a frame rate that is so out-of-spec.  The result is that speed runs will be affected because the Super Nt runs slightly slower than the original console.  After playing for ten minutes, the Super Nt will be one second behind the original system.  Ordinary play will not see a difference.  However, if you send the pure 60.0988fps signal to your TV or your capture device, the input device may drop a frame to keep video synchronization or may not be ideally synchronized with the audio.

Kevtris did come up with two solutions to the issue that he tested during development.  These solutions will make their way into the official firmware.  In the display options menu he included a "single buffer" option and a "full buffer" option.  The "single buffer" sends officially clocked 60.0988Hz video into his scaler which outputs 60Hz.  Because the input and output framerates differ, there will be a visible screen tearing line traveling down the screen.  The "full buffer" option eliminates the visible screen tearing at the cost of up to a frame of latency because a whole frame must be buffered.  An occasional frame will be dropped, but it will be difficult to notice.  The default slowed down 60Hz method will not have any added latency or screen tearing.



The key benefit to recreating the console in an FPGA is the elimination of two source of latency.  The first source of latency comes from the controller port.  You can eliminate this by using a wireless controller.  The second source of latency comes from emulators, which must figure out what a program is trying to make hardware do and fit it into whatever hardware resources an operating system can provide, which can add additional time.  The third source of latency comes from rescaling the video, whether to add filters or to increase the resolution.  You need only worry about the fourth source of latency, your TV or display.

Speaking of scaling, the SNES typically outputs at a 256x224 resolution, but a few games use 256x239, 512x224 or 256x480 (interlaced).  There will be options to stretch the horizontal and vertical dimensions and position.  The maximum scale will be 1080p/5x vertical, giving a resolution of 1280x1120.  40 resized/8 real pixels will be lost due to the resolution, but you should be able to shift the image up or down in case any information is lost.  Like the Nt Mini, the Super Nt will have a popup menu to adjust these settings at any time.

There will be a filter to add scanlines and to blend the high resolution images in a few games like Jurassic Park and Kirby's Dream Land 3 as shown for the latter game here : http://nerdlypleasures.blogspot.com/2015/03/the-case-for-composite.html  The real SNES supports 32 sprites per line, but the Super Nt has a 64 sprite per line option to reduce flicker.  The Nt Mini had a 16 sprites per line option for NES games that flickered because the real NES only supported 8 sprites per line.

While not many games use interlaced modes, most that do use interlaced resolutions in menu screens composed of static images.  For a game like R.P.M. Racing, which uses interlaced video in game, deinterleaving will be done via weave.  This will show the "mice teeth" artifacts on moving images, which is how bsnes/higan handles the game as shown here : http://nerdlypleasures.blogspot.com/2017/10/the-rise-of-interlacing-in-video-game.html  More advanced deinterlacing could remove the mice teeth artifacts, but it would require a frame buffer and introduce latency.  Some games like Ranma 1/2: Chounai Gekitou Hen enable interlacing in error, so there is an option to ignore the interlace setting for those games to avoid interlacing artifacts.

The SNES can be modded to output digital audio at 16-bit, ~32,040Hz.  Some receivers have trouble receiving an S/PDIF style signal at the slightly non-standard rate.  The HDMI standard supports 16-bit audio at 32,000Hz but some displays refuse to acknowledge that signal.  No displays have an issue with 16-bit at 48,000Hz, and that is what the Super Nt supports. Resampling 32KHz to 48KHz is much easier than resampling 44.1Khz to 48KHz. (Is anyone nostalgic for the days of the Sound Blaster Live! and Audigy's resampling?)

Peripheral support outside light guns should be as good as the original SNES.  You can use a multi-tap for the good three and four player games like Secret of Mana and the Super Bomberman series.  Kevtris tested it with a Sufami Turbo, a very odd Bandai product that lets you use up to two mini-cartridges.  Even more importantly, the device works with the Super EverDrive, the sd2snes and the Super Game Boy and Super Game Boy 2.  It also works with every expansion cartridge chip cartridge game including the Super FX, S-DD1 and SA-1.  Kevtris got it to work with the Nakitek Game Saver Plus and an old disk-based copier, the Bung Game Doctor SF6.  It works with the SNES Mouse as well.


The cartridge supports audio input and feeds it through a ADC before combining it with the SNES"s internal audio.  The Super Game Boy 1 & 2 and the MSU-1 of the sd2snes use this feature.  The Satellaview also used this feature through the expansion port for games that supported SoundLink, but the sd2snes can handle this through its MSU-1 support for games that have been hacked to support it like the BS Zelda games.  You can turn the audio input off and adjust its volume via the popup menu.  If you have a Super Game Boy, you will essentially be getting an additional system with HDMI for free.  The Super Game Boy feeds its video output through the SNES's PPUs whereas unofficial products like the Super 8/Tristar and the Super Retro Advance merely use the SNES for controller input and power.  Kevtris confirmed the Super 8 works on the Super Nt.

As with the Nt Mini, Analogue has partnered with 8bitdo to provide wireless controllers to match the enclosures of the Super Nt.  Wireless controllers are available for $39.99 at Analogue's site and come with a SNES-plug Retro Receiver.  One issue that people have been having with the wireless NES-plug Retro Receivers is that the signals from the receiver plugged into controller ports 1 and 2 interfere with each other.  On a NES, AV Famicom, NT and an Nt Mini the NES controller ports are packed in tightly next to each other.  On a SNES or Super Nt, they are separated by at least an inch, which may alleviate the issue.  8bitdo controllers and receivers rely on Bluetooth technology, so they come with the benefits and drawbacks inherent in the Bluetooth standard.

The use of plastic instead of aluminum gives us a console that looks like a video game console, not an Apple TV.  The plastic has been promised to be durable and hopefully should not yellow.  It also allowed Analogue to release the Super Nt in four different color variations without having to charge more for the non-standard colors.  The Nt and Nt Mini have or had non-standard color choices, but Analogue had to dye the aluminum, increasing the cost over the basic silver model.  The four choices are Classic (off-white & purple like the US SNES), SF (off-white and gray like the Super Famicom), Black and Transparent.  Unlike the Nt Mini's modern design, which has a single button for power and reset on the back of the console, the Super Nt has separate power and reset buttons on the top of the console.  I have include a photo of each color/design of the console with its corresponding 8bitdo controller from Analogue's press kit.  Analogue has adapted a new logo for the Super Nt and redesigned their site as well (it was down all of last weekend, now we know why).

Finally, the Super Nt is powered by a USB cable and adapter and includes an SD card slot for firmware updates like the Nt Mini.  Of course, the first thing that everybody who knows anything about the Nt Mini was pondering on the possibility of jailbroken firmware from kevtris containing cores to run other consoles and flash cart functionality for them and the SNES.  The official word from Analogue, via Polygon, is "“We don’t really discourage anyone to do anything with our products. You can do whatever you want with it. It’s not up to us, that’s not what we’re in the business of doing.” kevtris repeatedly replied "no comment" when asked about the possibility yesterday.  The Super Nt uses a Cyclone V FPGA like the Nt Mini, but is using the A4 instead of the A2.  The A4 has almost twice the on-chip resources as the A2, so systems like the Sega Genesis and Turbo Grafx 16 seem quite possible on the Super Nt.  Porting over the cores from the Analogue Nt would also appear possible.

Analogue never discouraged anyone from jailbreaking their Nt Mini and indicated they would not deem the one year warranty on the Nt Mini as being violated by using jailbroken firmware.  The Super Nt also comes with a one year warranty.  By comparison, the original Analogue Nt with the reclaimed NES CPU and PPU chips only came with a three month warranty and cost $579 with the HDMI upgrade.  Analogue is expecting pre-orders to ship in February of 2018, although given that the Chinese New Year will occur on February 16, 2018, March or even early April is a more realistic estimate.  Christopher Taber, Analogue Inc.'s chief corporate officer, will be spending this holiday season in Hong Kong to supervise production.  Kevtris has repeatedly stated that having "boots on the ground" is the only way to ensure that your Chinese factory will ship it right the first time.  The Nt Mini shipped in both its production batches with only a short delay from the initial estimated date.

Analogue made a later announcement that the Super Nt would ship with two games preinstalled.  The first is Super Turrican - Director's Cut.  This was the game originally designed to be released as "Super Turrican", but economics forced the developer, Factor 5 to accept a reduction in cartridge size from 3MB to 2MB.  The Super Nt will include the 3MB version Factor 5 wanted the world to play.  The second game is the sequel, Super Turrican 2.  A nice little bonus is that every Super Nt will come with a box for Super Turrican - Director's Cut.  The game will be built-into the system. 

No comments: