The video games Nintendo did not need you to play: Tengen
Not too long ago, I took a have a look at Nintendo’s MMC line of mappers, and another boards. All boards for the NES’ western releases needed to be manufactured by Nintendo, and they also typically met sure requirements set by Nintendo. However these guidelines had been enforced by expertise, not by regulation. And the corporate that had beforehand killed the American sport business determined to interrupt these guidelines. Insanity? No. This… is Tengen.
Tengenerations
We noticed Tengen within the NES weblog publish, the place they launched the video games Gauntlet and R.B.I. Baseball utilizing the DxROM household of circuitboards, which used a Namco-made mapper chip. Tengen’s licensed interval, nevertheless, solely appears to have lasted lower than a 12 months. Their first title, R.B.I. Baseball, got here out in April 1988, and in December 1988, Tengen introduced that they’d break with Nintendo and manufacture video games themselves, with a cultured black commerce gown with bigger artwork.
The Atari 2600’s demise is mostly blamed on a glut of low-quality cartridges, prompted partly by the console’s openness to unlicensed video games. (As Atari didn’t anticipate anybody to attempt to change into a third-party developer; the idea didn’t even exist but) In consequence, Atari collapsed in a flood of purple ink; its house client division was bought to Jack Tramiel, who largely needed the model to advertise his ST laptop and changed many of the employees. Avoiding that destiny is the explanation Nintendo put the licensing regime in place.
The arcade division, which was doing higher (although the American arcade market was already starting its decline with the tip of the Golden Age) remained in Warner’s possession and saved its employees, however adopted the title Atari Video games. Since Tramiel’s Atari Company owned the precise to the title for house merchandise, Atari Video games, arguably the extra direct descendant of outdated Atari, needed to give you a brand new model. And that model was Tengen.
In fact, Tengen wasn’t meaning to promote low-quality video games like those who had plagued the 2600. That they had Atari Video games’ library of arcade hits (like Gauntlet), in addition to NES video games from their sometimes-parent firm Namco, and rights to arcade titles from different corporations that had opted out of Nintendo’s licensing world, like Sega. That’s what makes Tengen stand out from different corporations that might make unlicensed video games like Colour Goals. This was a severe try by massive names within the enterprise to interrupt Nintendo’s licensing.
Comply with the Rabbit
The opposite factor that makes Tengen stand out is how they broke the Nintendo’s lockout chip. Fashionable consoles keep their lockout utilizing cryptography. However within the 1980’s, that might get your console categorized as a munition, and the NES’ 1.7MHz CPU would battle to implement something regardless. Plus, cryptographic locks had no authorized pressure on the time; this wouldn’t be the case within the US till the 1998 Digital Millennium Copyright Act.
So as a substitute, Nintendo developed a small microcontroller, which implements a program of sending random numbers forwards and backwards. The microcontroller within the console compares with one within the cartridge, and if their numbers don’t match the anticipated sample, it resets the console each second, stopping gameplay. The chip is configured so this system can’t be dumped simply, and in case you do dump it, this system is protected by copyright regulation.
Right here’s Camerica’s 1992 launch Micro Machines. You may discover some circuitry within the nook; what that is is definitely one thing we’ve lined on this weblog earlier than, a charge pump that produces a destructive voltage from the console’s 5V enter. When the console activates, a destructive voltage spike is shipped down the reset line of the lockout chip, frying it lengthy sufficient to interrupt its program and trigger it to not reset the console.
Why is there a change? As a result of the best way this circuit is designed, if there isn’t any lockout chip current, it’s going to simply draw massive quantities of energy from the console till one thing fails. And in 1993, Nintendo would launch a variant of the console that had no lockout chip. Previous to this, Nintendo would make different changes to the NES to attempt to forestall strategies like this; particularly, diodes had been positioned to interrupt earlier Colour Goals makes an attempt at frying the lockout chip’s information traces.
Far again in 1988, Tengen appears to have acknowledged this feature existed, however was an excessive amount of of a hack. Plus, a destructive cost shock may in idea danger damaging the console and leaving Tengen and its dad or mum, Atari Video games, liable to important damages. In order that they made their very own clone, the “Rabbit”, which really communicates with the console facet, and tips it into considering it’s only a common Nintendo chip.
How did they do it? Because it seems, crime. Unable to reverse engineer the chip, Tengen satisfied the USA Copyright Workplace at hand over the supply code of the lockout chip, claiming it was obligatory for a lawsuit. With the code in hand, Tengen may make their very own clone with ease. And Tengen was going to sue Nintendo for antitrust violations, in order that they most likely figured they might get away with it.
The Nintendo-Tengen saga led to an out-of-court settlement in 1994. That 12 months was the identical 12 months Tengen disappeared, as Atari Video games was subsumed into Time Warner once more, turning into a part of Time Warner Interactive. Whereas there have been injunctions in between (it appears they might have been pulled in 1992 and I’m unsure if that was ever reversed), which means that for a lot of the NES’ hottest interval, Tengen video games had been available on the market too, in case you may discover them. Let’s check out a few of them.
Pac-Man
Namco’s Pac-Man port is an NROM-128 sport, the best circuitboard that Nintendo bought within the west: 16kiB of program ROM, and 8kiB of character ROM. (My sport Aspect Star “N” additionally meets these restricted necessities.) However regardless of that, the sport appears to have one of the crucial convoluted launch historical past on the console. See TCRF for extra particulars; it had two Namco variants in Japan, and three North American releases: a licensed Tengen, this unlicensed Tengen, after which in 1993, Namco would launch it underneath a license once more.
So right here’s Tengen’s Pac-Man. This board is just about equivalent to Nintendo’s NROM-128, with the 2 ROM chips and the lockout chip. Which is sensible; that is just about precisely the identical sport as Tengen launched licensed a number of months earlier than, simply with out claiming to be licensed.
The one different mapperless sport Tengen would launch could be their tackle Ms. Pac-Man. Surprisingly, this can be a utterly totally different sport than Namco’s licensed model in 1994. (Nevertheless, it is extremely near the Genesis and Tremendous NES variations, additionally by Tengen)
Tetris
When many individuals assume Tengen and the NES, they assume Tetris. As I famous within the story of Bloxeed, the rights to Tetris are a downright mess. However one factor is for certain; Atari Video games positively had the arcade rights to the sport, which they launched in 1988. They positively thought that got here with the console rights, and deliberate an enormous launch for 1989. Nintendo and Bullet-Proof Software program outmaneuvered them, Tengen’s model was recalled instantly, and is now fairly uncommon. Finish of story, proper?
Tengen’s Tetris makes use of a novel circuitboard; the sport is pricey sufficient that I don’t have it right here to indicate you, but it surely’s really equivalent to the usual Nintendo CNROM, a discrete-logic mapper utilized in video games like Championship Bowling. Typically, Tengen appears to have most well-liked ASIC mappers, so it’s attention-grabbing that this specific sport used discrete logic; maybe it’s as a result of they anticipated it to promote in excessive numbers and wanted chips they might shortly get ahold of?
One other attention-grabbing factor about Tengen’s Tetris is that it might really be the fourth Tengen sport to be licensed by Nintendo. What are you speaking about, Nicole? Because it seems, Tengen test-marketed their Tetris utilizing Nintendo’s arcade VS. platform. So far as I can inform, this was all official and above-board, and was previous to the December 1988 break between Tengen and Nintendo; I’m pleased to be corrected– it’s a bit odd that this model of Tetris makes use of the Tengen title when Atari had full rights to make use of it in arcades.
The screenshot is from the MAME emulator.
MIMIC-1
Again within the final article, we checked out Gauntlet, whose licensed incarnation used a Namco 109 chip. This chip offered very versatile CHR and PRG banking much like Nintendo’s MMC3, however that’s all it did, with out assist for software-controlled mirroring, IRQ-timers, or different superior options that Nintendo would add to their model.
Since this used a Namco chip, and Tengen was fairly pleasant with Namco (in spite of everything, Namco owned a bit of the corporate), you may anticipate the Namco chip for use of their circuit boards too. You’d be incorrect.
Just like the Nintendo-manufactured model, this contains a lockout chip (a Rabbit), a 74-series logic chip, program and character ROMs, a VRAM chip for 4 nametables, and a closing chip for mirroring. However there are variations too. For one factor, the Tengen board has no solder masks. What’s the take care of that, Tengen?
The extra attention-grabbing factor is that Tengen manufacturered their very own clones of the Namcot 109 chip. Normally referred to as the MIMIC-1, it has all of the capabilities of the Namco chip, however makes use of a extra regular pin spacing and a bigger bundle. So far as I can inform, all Tengen boards utilizing this chip use the Tengen-manufactured model. Being a part of Atari Video games, after all Tengen had loads of ability making their very own chips.
MIMIC-1 was the commonest Tengen unlicensed mapper, being utilized in video games like Tremendous Dash (above), the R.B.I. Baseball sequence, Pac-Mania, Toobin’, Vindicators, and extra.
To date, we’ve seen Tengen boards that don’t really supply something new to the NES. The MIMIC-1 is only a clone of the chip used on DxROM circuit boards. From Tengen’s perspective, after all, they seemingly did lower your expenses manufacturing in-house and avoiding Nintendo’s licensing. However in the USA, antitrust regulation is meant to be about client profit.
Most likely the strongest case for Tengen that Nintendo’s licensing harm shoppers was their launch of the Sega arcade title After Burner, which they launched in 1989.
After Burner is a fast-paced arcade-style shooter the place you pilot a fighter jet, taking off from an plane service and preventing enemies. And this port is truthfully actually good, much better than an NES sport primarily based off of After Burner has the precise to be. And it’s by top-of-the-line builders for the NES: Nintendo licensee Sunsoft, who made Blaster Grasp, Spy Hunter, Batman, and a complete host of titles.
It even maintains one of many key results of the arcade sport; the entire viewpoint swinging round at dramatic angles as you progress your craft whereas quickly animating ahead. It offers a convincing impression of swinging round at excessive speeds, despite the fact that the NES after all doesn’t include the total cockpit possibility the arcade sport had.
So how did Sunsoft do it? After Burner makes use of a customized chip, the Sunsoft-4. Now, the Sunsoft-4 was not utilized in any video games manufactured by Nintendo; this sport is the one time it made it outdoors of Japan. (Nevertheless, the later Sunsoft-FME7 was used within the Nintendo-manufactured sport Batman: Return of the Joker and several other extra in Europe) Right here, Tengen appears to have manufactured their very own model.
Probably the most attention-grabbing factor concerning the Sunsoft-4 is the usage of ROM nametables. Up till this level, we’ve assumed that nametables are in video RAM. Accessing video RAM is sluggish; you’ll be able to solely do it in VBlank and need to undergo the PPU’s registered. NESdev recommends planning to have solely 160 bytes modified in a body, plus the DMA for sprites.
One full nametable, although, is 960 bytes, assuming you give all of them the identical palettes and don’t want to vary the attribute tables (in case you do, then you definately want a full kilobyte). So how does After Burner swing the entire display screen like that? Altering midway by a body would produce a fairly ugly transition impact. However, although, After Burner’s nametables are extremely predictable. They don’t change primarily based on the place you might be within the stage, simply primarily based on the place of your aircraft. This makes it an ideal usecase for storing them prematurely. The Sunsoft-4 can embrace precomputed title tables in ROM, and with 128kiB, you have got 128 nametables, greater than sufficient to present After Burner its rapid-fire adjustments and quick animation.
Now, the factor is, we don’t know why Sunsoft and Tengen partnered for this sport. It’s unlikely it was due to Nintendo and Sega, regardless of what you may assume; Sunsoft was licensed by Nintendo in Japan. (In Japan, the licensing program was a lot much less strict, and individuals may nonetheless manufacture their very own cartridges) Like Gauntlet, After Burner requires a devoted circuitboard design only for it. So it’s positively potential to see how Nintendo’s hefty licensing charges would wipe out the potential for revenue.
One factor value noting, although, is that Sunsoft’s Japanese launch of After Burner II (regardless of the title change, the identical sport) is considerably upgraded, with issues just like the candy title display screen animation above that the US didn’t get. It appears that evidently Tengen put a while stress on the workforce, leading to an unfinished model of After Burner making it to America, whereas Sunsoft gave their builders a bit extra time to complete the sport earlier than releasing it in Japan. It wasn’t all sunshine and roses at Tengen.
Cease: Rambo time
Lower off from Nintendo, Tengen couldn’t use the MMC3, and needed to make their very own iteration of the Namcot 109 to get these great additional options.
So anyway, more often than not, Tengen needed to make their very own iteration to get some great additional options. And this chip known as the RAMBO-1. Since we now have time, let’s check out 1990’s Klax.
One attention-grabbing factor concerning the RAMBO-1 is that it consists of the Rabbit chip on-die. So far as I do know, Nintendo by no means mixed the mapper and lockout chip right into a single chip.
The NES Klax is a fairly respectable tackle the falling-tile arcade sport. It’s additionally very colourful and diverse, with a number of tiles on display screen. Tiles within the literal sense of 8×8 PPU tiles in addition to the sense of the falling tiles in sport. RAMBO-1 provides an analogous scanline counter IRQ to MMC3.
It’s so much like MMC3, in truth, that Hudson Tender licensed the Tengen model of Klax for launch in Japan, and used the Nintendo chip for it. The sport makes use of very cautious timing to continuously change out the display screen for issues like messages, even mid-scanline. Raster results like this typically require the entire CPU’s time, however Klax’s sport logic is comparatively easy, so it may well do issues like this.
The RAMBO-1 counter is a bit bit extra superior than MMC3; it may well additionally depend CPU cycles as a substitute of scanlines. If timed from an NMI to maintain issues synced with the PPU, they can be utilized for comparable results; in truth, the Famicom Disk System model of Tremendous Mario Bros. 2 makes use of a CPU counter for its standing bar.
Rolling Rolling Rolling
Namco’s personal successor to the Namcot 109 was the Namcot 163. This chip is commonly used within the chiptune scene for its superior audio capabilities, however these aren’t accessible to a western NES, even for unlicensed video games. It had a CPU cycle counter however no scanline counter. Tengen did port over one Namcot 163 title to their very own RAMBO-1 chip: Rolling Thunder. This sport got here out in late 1989; it might be the primary RAMBO-1 sport.
One factor you may discover is that there’s an additional chip on the Rolling Thunder board versus the Klax. They use the identical circuitboard, however there’s a chip unpopulated on Klax. As we will see, it’s a easy 74LS32 logic gate; a set of 2-input OR gates.
What is that this chip doing? Discover that the CHR-ROMs are the identical dimension; nevertheless, Rolling Thunder makes use of 128 kiB of CHR-ROM, whereas Klax makes use of 64 kiB. The additional chip, due to this fact, simply adjusts for the differing pinouts of various ROM chips. I’m assuming this was a cost-saving measure to reuse the identical board; given they but once more prevented utilizing solder masks, pennies had been seemingly being pinched.
Rolling Thunder is a fairly respectable port of the arcade sport. Graphics are after all massively downplayed, however I feel the gameplay survives fairly properly. On NES, I desire it to the also-Tengen-published port of the same sport Shinobi, which additionally makes use of the RAMBO-1.
At present affected by ‘Alien Syndrome’+++!
One other RAMBO-1 sport, this time with a novel configuration? And a port of a Sega arcade sport? Don’t thoughts if I do! And with out solder masks? That I thoughts, what’s your downside Tengen?
Alien Syndrome is a 1989 port of the 1987 Sega arcade title the place you roam a big scrolling map, in search of your comrades after which in search of the best way out. Since there’s no additional RAM on the cartridge and also you scroll in two instructions, you received’t be shocked to see some graphical glitches.
So, how are the nametables organized right here? Vertically? Horizontally? Neither! This has an adjustment on the PCB to make use of single-screen mirroring. Basically, as a substitute of controlling the association of the 2 nametables within the console’s built-in CIRAM, the sport cartridge controls it so you’ll be able to change between them, however they cowl all 4 components of the display screen.
At line 0, the nametables in Alien Syndrome appear to be this:
However as soon as it’s drawing the display screen the place your character strikes, issues change to appear to be this:
This single-screen nametable scrolling just isn’t that totally different from the Sega Master System, with the added draw back of attribute conflict. In any case, although, it doesn’t really require RAMBO-1 to drag off; the Japanese launch of Alien Syndrome, one other Sunsoft launch, makes use of the Nintendo MMC1 for a similar end result.
It’s a bit amusing to see these Sega titles in Tengen’s problem to the console licensing regime; the Sega Grasp System had an analogous licensing regime, and Sega themselves would sue Accolade, who broke the Sega Genesis scheme later in 1991. (From a technical standpoint, although, the 2 programs had nothing in widespread, the NES system counting on copyright and a difficult-to-reverse engineer technique, and the Sega technique relying nearly fully on trademark)
Tengen Seal of Amount
So Tengen’s plan to destroy Nintendo’s licensing regime could have failed. However they did depart behind fairly a legacy; given the carts are broadly obtainable to today, aside from Tetris, they should have made some respectable gross sales. How a lot of that cash Nintendo’s attorneys allow them to preserve, although, is misplaced to sealed settlements. At the moment, after all, the console licensing enterprise is as sturdy because it’s ever been, and with cryptographic locks and on-line shops, there’s not a lot any enterprising Tengen of as we speak may do.
However, Tengen not solely additionally used a non-standard screw kind on their cartridges, put one of many screws behind their sticker on the again. Even Nintendo didn’t try this!
