Switch cartridge stamp codes [WIP] (help needed!)

[re4mat | 65]

This thread is for decoding the 11-character stamp codes found on the backs of Nintendo Switch cartridges.
 

Submit your data for the spreadsheet!

I think this is something we can fully figure out with enough data. I've set up a spreadsheet on Google Docs that I'll add to as more data comes in:

https://docs.google.com/spreadsheets/d/1v1eyNa4w1ATrffomoxE4s5TANTmsRh7gv9AwO0ZUCTU/

If you're feeling helpful, please post your game(s) to this thread and I'll add them to the spreadsheet. I would ask that you provide, at minimum, the name of the game, the full product code on the front label, and the stamp code on the back, as well as a photo of the back so that I can visually verify the package type. If you're feeling more adventurous and don't mind opening your cartridge at your own risk, a photo of the top of the ROM chip that's high-enough resolution to be able to read the writing on it would be a huge bonus. Be aware that opening a cartridge means it will have to be re-glued in order to reassemble the cartridge to make it playable again.

Over the next year I intend to purchase some loose cartridges (especially copies of 1-2-Switch) for the express purpose of opening them up, so don't feel like you have to open up your own games. It would just be some nice data to have.

And if you have any special cartridges, like demos, prototypes, dev carts, anything like that, please submit as much information as you can, including photos.

And now, let's decode some stamp codes!

 

Intro

I'd been looking around for information on decoding the stamp codes on the backs of Switch cartridges, with the hopes of figuring out what they actually mean. What I found, however, was a lot of inconsistent and sometimes contradictory information out there. It took a lot of digging, research, and analysis, but I believe I've sifted through everything out there and have been able to use that to get us most of the way towards learning the actual meanings behind these codes.

Starting off, I found this page, where a resourceful person has been compiling a list of cartridge revisions. It turns out this was pretty helpful for the purposes of decoding those stamp codes. There's a rather large table there showing the correlations between builds, ROM revisions, and software versions, and it served as a good jumping-off point.

For reference, here's the Switch games I own physically as of this writing, along with their product codes and stamp codes, and some release dates (which may or may not line up with the physical releases):

Game Title	Product Code	Stamp Code	Release Date
Angry Video Game Nerd I & II Deluxe	LA-H-AYGRA-USA	AYGRA13Y000	May 2022 (approx.)
Cadence of Hyrule: Crypt of the Necrodancer	LA-H-ASWBD-USA	ASWBD11B000	June 13, 2019
Chrono Cross: The Radical Dreamers Edition	LA-H-AYZEA-ASI	AYZEA13X000	April 26, 2022
Hyrule Warriors: Age of Calamity	LA-H-AXEAB-USA	AXEAB09X000	November 20, 2020
Killer Queen Black	LA-H-AQJ8A-USA	AQJ8A20B000	October 11, 2019
Legend of Mana	LA-H-AZV8A-JPN	AZV8A13A000	June 24, 2021
The Legend of Zelda: Breath of the Wild	LA-H-AAAAA-USA	AAAAA08X000	March 3, 2017
The Legend of Zelda: Link's Awakening	LA-H-AR3NA-USA	AR3NA13A000	September 20, 2019
The Legend of Zelda: Skyward Sword HD	LA-H-AZ89A-USA	AZ89A41A000	July 16, 2021
The Legend of Zelda: Skyward Sword HD	LA-H-AZ89A-EUR	AZ89A11A000	July 16, 2021
Metroid Dread	LA-H-AYL8A-USA	AYL8A41A000	October 8, 2021
Octopath Traveler	LA-H-AGY7B-USA	AGY7B41B000	July 13, 2018
SaGa Frontier Remastered	LA-H-A2AXA-ASI	A2AXA12A002	April 15, 2021
Teenage Mutant Ninja Turtles: Shredder's Revenge	LA-H-A3UVA-USA	A3UVA12Y001	June 16, 2022
Xenoblade Chronicles: Definitive Edition	LA-H-AUBQA-USA	AUBQA22A000	May 29, 2020

 

Game type (1st character)

The first character of the stamp code would seem to follow the convention of game product identifiers for NDS and 3DS games using that to denote the game type, in which an A or B indicates a regular retail release. It would be interesting to see if we can corroborate this further. For example, if anyone has a demo, then that character should (in theory) be a letter (or number) other than A or B. There are some kind of demo or development cartridges which appeared on eBay awhile ago which have a 1 for the first character, though their stamp codes are 14-characters long. More on these special cartridges later.

One thing to note is that my copies of Breath of the Wild, Link's Awakening, and Octopath Traveler are marked on their game cases "Not For Resale", but the cartridges' product codes and stamp codes all begin with an A. So there does not seem to be a special letter designation for NFR releases.

 

Product identifier (2nd through 4th characters)

The first five characters in the stamp code match the 5-character portion of the product code shown on the front label. (The part between LA-H- and the region code.) According to that ROM revisions page, the first four characters of that section are the product identifier, and the fifth character is the build. (We'll discuss that next.) As stated above, I believe the first character is the game type, which would make characters 2, 3, and 4 the product identifier. For example, Breath of the Wild's product identifier would be AAA, while Link's Awakening would be R3N. Wikipedia, while having no guarantee of completeness, lists 4,483 Switch games. With 45,323 possible combinations of letters and numbers, I should think that three would be more than enough characters to use for uniquely identifying all Switch games across the lifespan of the console, and it's likely Nintendo thinks the same.

 

Build (5th character)

The 5th character is a letter, with the most common so far being A. There is a page I found on gameverifying.com which states that the 5th character is used to denote language and/or region. While language sometimes comes into play for this character, the hypothesis that this character is used solely for language and/or region can be be disproven just by the physical Japanese releases of Breath of the Wild. The regular JPN BotW cartridges have a product code of LA-H-AAAAA-JPN, while the physical Breath of the Wild + Expansion Pass release has a product code of LA-H-AAAAG-JPN. Both cartridges are Japanese region games, and both cartridges have the same languages. If the 5th character was used just to indicate language and/or region, those two releases would share the same value.

 

Spoiler

Front label for Breath of the Wild + Expansion Pass, showing the product code

 

Spoiler

Back of Breath of the Wild + Expansion Pass cartridge, showing stamp code and LGA package type

 

Indeed, the only difference between the two games is the build — with A being the base game and G being the base game + expansion pass content. It is curious that the latter didn't use a B for the fifth character, but it's possible that letters B through F are in use on versions of the game that we don't have evidence for as yet. For example, a demo build, or builds specifically made to be sent out for review by journalists, Nintendo Partners, ratings agencies, etc. It would be interesting to see if copies of BotW exist out there which have different letters for the 5th character, and seeing if the difference for those, too, is simply the build of the game.

Some build changes do seem to be simply a difference in region, such as .hack//G.U. Last Recode, in which A is the Japanese build and B is an international release. It would be interesting to know what the actual difference is between those two builds.

Others, like AI: The Somnium Files: nirvanA Initiative or Aragami: Shadow Edition seem to just be a difference in publisher. For differences in publisher, there doesn't seem to be any correlation between the letter used and which publisher a game is released by; they just seem to start with A for the first one, B for the second, etc.

Either way, the current evidence does seem to point to the 5th character being used to indicate which build of a game is on the cartridge. I believe that page I linked to at the top of this post had this right, and I'm okay with accepting it.

 

ROM Revision (9th through 11th characters)

The last three characters in the stamp code are numbers, which count up from 000 and are reset back to 000 with new builds. They seem to line up quite well with the ROM revision, and I believe they got that correct as well on that page I linked to at the top of this post. As I mentioned, they've compiled into a table the relationships between ROM revision numbers used in the stamp codes and software version numbers used in the game binaries, and the evidence seems pretty clear. Since ROM revision values can be the same between builds, a game with build A could have ROM revision 000, and the same game with build B could also have ROM revision 000, but they would still be different ROMs, with different software version numbers, different checksums, etc.

Though I must say it does seem a little weird to have 3 characters reserved for this. What game is going to have more than 100 ROM revisions? Perhaps the 9th character is actually for something else that hasn't changed at all over the years? Like a hardware revision that hasn't changed because they haven't needed to change the hardware at all? Interesting to speculate on, but doesn't make much of a difference for our purposes, unless we ever see a number other than 0 appear there. Either way, that leaves the 6th, 7th, and 8th characters to figure out.

 

6th and 7th characters

The 6th character seems to be either a 0, 1, 2, 3, or 4. I haven't found any other numbers, but if you have a cartridge with a different number, please post a photo!

The 7th character seems to be a digit ranging from 0 to 9, however I have yet to see a 5 or 6.

So far, I've seen that the 6th and 7th characters are found in 13 specific combinations:

• 00
• 08
• 09
• 11
• 12
• 13
• 19
• 20
• 22
• 27
• 30
• 34
• 41

I found this to be interesting, and may indicate that the two characters are together denoting a single property. As we get more data in, we may find more combinations, so I'm not sure we can draw any conclusions from this yet. It may turn out that a full range of cartridges from 00–99 is out there.

So what could those characters represent?

 

Manufacture date

I included release dates in the table at the top of this post to see if I could find a correlation, but there doesn't seem to be one. For example, yes there's a 2 in the Shredder's Revenge code and the game was released in 2022, but there's a 3 in the same spot on Chrono Cross' stamp code, and that game was also released in 2022. Now obviously production starts before the game is actually released, and may even begin production in the previous year, but even taking that into account there still doesn't seem to be anything that lines up with the year. (My copy of Chrono Cross was purchased on release day, so definitely was not produced in 2023.)

I also considered the release year of the Switch being used as a baseline that perhaps one of the numbers in the stamp code counts up from. The Switch was released in 2017, so for example maybe that year could be represented by a 0, and 2018 by a 1, 2019 by a 2, etc. But again, looking at Breath of the Wild in the spreadsheet would seem to disprove that. Here it's clear that there's no correlation at all, as there's a revision 002 cartridge with 22 for the 6th and 7th characters, while a revision 001 cartridge has 34, which would make the cartridge with a later revision produced earlier than one with an earlier revision. This is incredibly unlikely.

So I think it's safe to say that the production year is not part of the stamp code. And if the year is not included as part of the stamp code, then it definitely wouldn't make sense for the month or day to be a part of it, either. There's very limited space in those stamp codes, so I'm sure Nintendo wants every bit of information in there to be usable in tracking down sets of cartridges in case of defects/recalls/etc. Knowing the month and/or day a cartridge was produced, but not the year, would not be a useful piece of data to have.

 

Developer/publisher

There also doesn't seem to be any correlation between developer or publisher. For example, just in the Nintendo-made games in my collection, for the 6th and 7th characters I see 09, 08, 13, 41, 11, whereas you would expect all Nintendo games to share the same number. Likewise, some of those numbers are shared with other games from different developers/publishers, like AVGN, Chrono Cross, Legend of Mana, and Octopath Traveler.

 

ROM chip capacity

One thing to consider could be chip capacity. We know that there are several chip capacities in use for Switch cartridges, including 4Gb, 8Gb, 16Gb, 32Gb, 64Gb, 128Gb, and 256Gb chips. However, there doesn't seem to be a correlation here, either. For example, Breath of the Wild uses a 128Gb (16GB) ROM chip, but we see different numbers for the 6th and 7th characters between different BotW cartridges. If these numbers represented chip capacity, we would expect them to be the same across all copies of a game.

 

Location of manufacture

Another thing to consider would be where the cartridge was manufactured. This gets a little tricky, though, as there's not much (or really any) information on where cartridges are actually manufactured. According to some news reports I could find, Nintendo's current manufacturing sites are in China, Vietnam, and Malaysia, however I can't find anything more specific than that. They have three manufacturing partners: Foxconn, Hosiden, and Sharp. Hosiden has 19 manufacturing sites throughout various countries, and I can find no information on which ones are used by Nintendo. Nintendo announced in 2019 that some manufacturing for Switch would be moved to Vietnam, and Sharp began manufacturing for Nintendo in Malaysia in 2020. I've noticed, however, that the packaging for all my Switch games say that they are made in Japan. The bottom of my BotW Special Edition box explicitly states that the game was made in Japan, while the coin and case were made in China.

 

Spoiler

Bottom of my Breath of the Wild Special Edition box with "game made in Japan" note

 

At least one Chinese Switch game (New Super Mario Bros. U Deluxe) explicitly states on the back of the case that the cartridge was made in Japan and the package was printed in China. It's hard to draw any firm conclusions from all of this, but it does seem as though the Switch console and various accessories are made in China, Vietnam, and Malaysia, while the cartridges themselves are made in Japan. If this is the case, then the wide range of numbers used for the 6th and 7th characters together would seem to preclude their being indicators of manufacturing site — unless there are 13, maybe more, cartridge manufacturing sites in Japan, which sounds unlikely. The 6th character alone has five confirmed numbers (0–5) and it is a little bit more believable that there are five manufacturing sites rather than 13, but either way there is no evidence for how many cartridge manufacturing sites there are, or where specifically they are. Until there is, I'm not going to assume that either the 6th or 7th characters are used to denote manufacturing site, as there is not enough data to be able to say so definitively and we want to be open to other possibilities if the data leads us in another direction. If anyone has any more evidence of where Switch carts are manufactured, please let me know!

 

Batch number

There could be a batch number in there, and that would make sense as a piece of data that Nintendo would want encoded onto that stamp. (For example, if there's a defect that needs to be recalled/replaced/etc., it would be helpful for tracking down affected cartridges.) There are two copies of Mario Kart 8 Deluxe in the current data set which have identical stamp codes, differing only in the region code in the product code on the fronts of the cartridges. (EUR vs. AUS) If either the 6th or 7th characters are for denoting batch number, that could imply that cartridges for multiple regions may be manufactured in the same batch. Or it could be a coincidence, if different regions are produced in different batches and they just use the same method of counting batches.

One thing that stands out to me is those three European versions of BotW that differ only in their ROM revision numbers, however it's still too small of a sample size to be able to gleam anything definitive out of that. Perhaps some of you fine people could post your BotW stamp codes so we can add them to the list? (Be sure to also include a photo of the back of the cartridge so that I can verify the chip package type!) Either way, the apparent randomness in those numbers could very well be related to a batch, though those two European versions both being 22A but different ROM revisions might also disprove that hypothesis, unless batch numbers get reused somehow. (Say if batch numbering resets with each new revision.)

Another thing worth noting is that my copies of Skyward Sword HD were both purchased on launch day, and their stamp codes only differ in the 6th character. They are from different regions (USA vs. EUR) but if cartridges for different regions are manufactured in the same batch, it could mean that the 7th character is the batch number, and the 6th character is for something else. (Perhaps manufacture site?)

 

8th character

The 8th character is a letter, and seems to be either A, B, S, X, or Y. So far, A is far and away the most common, followed by B. In comparison, X, Y, and S are relatively rare in the current dataset. This frequency distribution may change as more data comes in, but it's still interesting.

I've found one other letter, though I don't know about its authenticity. There is a so-called  "dummy" cart of Breath of the Wild that has an F, which is claimed to be authentic. Internally, the cart differs from every other BotW cart we've seen. Most notably, of course, is the lack of a ROM chip altogether. However the presence of a PCB on which to mount a TSOP chip is odd, since every copy of BotW I've seen so far uses an LGA package, not a TSOP, and so does not have a PCB like that inside the cartridge. Additionally, the first five characters are made up of the name KYOTO, which I would guess is in reference to the location of Nintendo's headquarters. The remaining characters in the stamp code match the schema as normal.

 

Spoiler

Unverified "dummy" cartridge, disassembled and showing the peculiar stamp code and unpopulated TSOP-style PCB

 

I also found this thread over on GBAtemp that has more stamp codes listed, and I've been adding those to my spreadsheet, as well as some other cartridges that I've been finding on eBay. Mostly I've been specifically looking at the listings from one seller, who sells a lot of loose cartridges and takes good photos of the front and back. Basically, so long as a cartridge has the product code and stamp code visible, I've been adding it to the spreadsheet. Going forward, however, I'm going to only be adding games to the spreadsheet that have, at minimum, the product code, stamp code, and confirmation of chip package type. (More on that below.)

 

Language/region

The page that I got that dummy cart image from speculates that the 8th character denotes language and/or region, but I don't think this is the case. (It also states that the 5th character is used for language, which is confusing and muddies up their own schema.) In fact, I believe this character is related to the ROM chip used in the cartridge, which I'll address later. But to continue with why it doesn't make sense for the 8th character to be language and/or region, just in my collection alone there's USA carts with A, B, S, X, and Y. If it was for a region or language, then it wouldn't make sense for USA carts to be included in all five.

Furthermore, there are 8 regions I’ve seen in product codes so far: JPN, USA, EUR, AUS, CHT, CHN, KOR, and ASI. That’s more regions than values seen for the 8th character.

 

A brief detour into language/region for the 6th and/or 7th characters

That GBAtemp thread also speculated that the 6th and 7th characters are used for region and/or language, but I don't think this is the case either. While my copies of Skyward Sword HD for USA and EUR differ only by the 6th character, there doesn't seem to be any correlation between all the other games in my spreadsheet and region.

Another nail in the coffin for language/region being encoded into the 6th and/or 7th characters: the 6th character in all the stamp codes in my current dataset is a 0 through 4, which is not enough values to use for all the regions. Likewise, the current dataset only has a 0–4 and 7–9 for the 7th character, which is more values than needed for all the regions.

Now, of course, it may be that there is a full range of 00–99 for the 6th and 7th characters, and it may also be that there are cartridges from more regions with more languages out there, but based on the evidence we have right now, region and language doesn’t seem able to fit into those characters at all.

We can also use the values themselves for those characters to rule out language/region being encoded into the 6th and/or 7th characters.

The game that we have the most stamp codes for so far is Breath of the Wild:

• LA-H-AAAAA-USA /  AAAAA08X000
• LA-H-AAAAA-USA /  AAAAA34S003
• LA-H-AAAAA-USA /  AAAAA12A000
• LA-H-AAAAA-EUR /  AAAAA22A000
• LA-H-AAAAA-EUR /  AAAAA22A001
• LA-H-AAAAA-EUR /  AAAAA22A002
• LA-H-AAAAA-EUR /  AAAAA34X001
• LA-H-AAAAA-EUR /  AAAAA43A000

While the first glance of this data subset would make it seem that 22 at least is exclusive to EUR cartridges — one could surmise that it refers to a specific sub-region of the EUR, such as the UK/English or German, which is data I haven't been collecting — however that's quickly disproven by the appearance of 22 in several USA cartridges, such as my copy of Xenoblade Chronicles: Definitive Edition. It seems quite clear that neither of those characters are related to region.

Similarly, I don't have data on the language(s) on each cartridge. However, given the frequency distribution of the various values for the 6th and 7th characters, especially with regards to USA-region cartridges, and especially with regards to how the same game from the USA region is shown in several cases to have different values for those characters, I think it's safe to rule out either of them being related to language, either.

 

ROM chips

There are different manufacturers for the ROM chips inside the game cartridges, however. Macronix seems to make the majority, while Lapis manufactures a couple smaller ones. as well as a 256Gb chip. Here's a list of known chips — along with their manufacturers, package types, and sizes — used in Switch games:

• MR20RG1410E (Lapis, TSOP, Size unknown — see below)
• MR20RG2410D (Lapis, TSOP, 4Gb / 0.5GB)
• MX23J8GL0 (Macronix, TSOP, 8Gb / 1GB)
• MR20RG4410E (Lapis, LGA, 16Gb / 2GB)
• MX23J16GL0 (Macronix, TSOP, 16Gb / 2GB)
• MX23J32GL0 (Macronix, TSOP, 32Gb / 4GB)
• MX23K64GL0 (Macronix, LGA, 64Gb / 8GB)
• MX23K128GL0 (Macronix, LGA, 128Gb / 16GB)
• MX23K256GL0 (Macronix, LGA, 256Gb / 32GB)
• MR20RG5410E (Lapis, LGA, 256Gb / 32GB)

There may be more, but I have not as yet found any evidence of them. Switch Brew lists four manufacturers (curiously none of them being Macronix, the manufacturer for which we have the most evidence) but other than Lapis I can't find any evidence to back up their claims. If anyone here is from the Switch Brew scene, I'd be interested in learning how they were able to derive that list of manufacturer names.

 

Chip package types

The chips used are produced either as 16-pin LGA packages or 48-pin TSOPs. The LGAs have the cartridge pins built directly into the package, whereas the TSOPs are soldered onto a separate PCB which has the cartridge pins on it.

 

Spoiler

Front of a Breath of the Wild cartridge removed, exposing a 128Gb LGA chip

 

Spoiler

Close-up of the top of a 128Gb LGA chip from Breath of the Wild

 

Spoiler

Back of a Breath of the Wild cartridge, showing bottom of 128Gb LGA chip

 

Spoiler

Close-up view of the top of a 48-pin TSOP chip and PCB that's been removed from a 1-2-Switch cartridge

 

Spoiler

Bottom of a PCB with its 48-pin TSOP chip removed

 

Spoiler

Back of a Hello Neighbor: Hide & Seek cartridge, showing bottom of PCB for a 48-pin TSOP chip

 

Solving the 8th character

So based on the evidence I can find, there are two chip manufacturers (at least; more on this in a minute) and two package types, which would give four combinations of manufacturer/package type. So it's possible — dare I say likely — that this is where the 8th character comes in to play. I first noticed that Breath of the Wild only uses LGA chips in their cartridges (that "dummy" cartridge notwithstanding) and had only A or X for the 8th character. I thought this might be a correlation, so I started collecting more data and plugging it into my spreadsheet. Then I encountered a copy of Pokémon Brilliant Diamond which had an S for the 8th character. At first, it was the only game I'd seen with an S and so I was a little suspicious of its authenticity. However the photo of the back of the cartridge clearly showed that it was in an LGA package. Then I spotted a copy of Metroid Prime Remastered with an S, and it was also in an LGA package! Then, in a bid to get yet more data, I asked a good friend of mine to go through all of his cartridges and tell me what the product codes, stamp codes, and package types were. It turns out his copy of Breath of the Wild is also an S! And of course it's in an LGA package, as all BotW ROMs seem to be. I started going through all the data and spotted what looked like a pretty strong correlation: A, S, and X only appeared on cartridges with LGA chips, and B and Y only appeared on cartridges with TSOP chips. In my spreadsheet, I built formulae which went through the game list and calculated a percentage match for each game based on this hypothesis, excluding games without photos since those are needed to verify the package type. And sure enough, there is a perfect match! Across the board, there's a 100% correlation between the letter used for the 8th character and the type of package used by the ROM chip. It could also explain what the F is in that "dummy" cartridge’s stamp code (assuming that it's a legitimate Nintendo-manufactured cartridge): the F could mean that there is no ROM chip at all. Even the demo/dev carts I go over below have an X in their stamp codes, and all have an LGA package! It's downright predictive at this point!

But that leaves the question of why there are two different letters used for TSOP packages and three for LGAs. I suspect that these are different based on the chip manufacturer. There's not a whole lot of data at the moment, but so far I've got four games that have been opened and which we have the chip manufacturer and stamp code for. So based on that, I've come up with the hypothesis that the letters denote the chip manufacturer as follows:

A	Macronix
B	Macronix
S	Unverified
X	Lapis
Y	Lapis

We have yet to see any games with an S in the code opened, so we don't know yet what brand of chip is used in those. (Maybe the S stands for Samsung? Who knows?) We also don't have any opened cartridges for B or X, but I think it's likely that the former is Macronix and the latter is Lapis. Those two letters denote TSOP and LGA packages, respectively, and we know that Macronix and Lapis both make TSOP and LGA chips which are used in Switch cartridges. Since there are two letters each to denote TSOP or LGA packages, it makes sense that each letter per package type would denote the manufacturer. The data set here is incredibly small at the moment, but so far what is there shows a 100% match.

I'm curious to see if there are any other letters out there; perhaps the manufacturer of the chips used in cartridges marked with an S also provide TSOPs for Switch cartridges which have a different letter we haven't seen yet, or perhaps there are even more manufacturers providing chips for Switch games. I also wonder if the S is from Nintendo finding a third supplier to shore up cartridge production in the face of the global chip shortage from 2020–21.

 

Lapis MR20RG1410E chip capacity

I wanted to put this in its own section because currently it's the only chip which has been identified but whose capacity is unknown. I've seen this chip used on two games: 1-2-Switch and Axiom Verge. I asked Tom Happ, creator of Axiom Verge, what size the ROM was that he submitted to Nintendo for manufacturing, and he replied that it was under 500MB. Unfortunately, that didn't end up narrowing things down. I did, however, find a way that we could figure it out.

On the ReSwitched Wiki, there's a page on Switch cartridge hardware which shows a teardown of a 1-2-Switch cartridge. Unfortunately, the images on the page are incredibly tiny and don't have enough resolution to be able to read the chip's part number. (Or the stamp code on the back of the cartridge, which would have also been nice.) BUT the Macronix logo is plainly visible, and we do know the capacities of all the Macronix chips. Since it is incredibly unlikely that one game would use chips of different capacities, then if we can get the part number of the Macronix chip used in some copies of 1-2-Switch, then we'll know the capacity of the chips used in the game, including that of the Lapis MR20RG1410E!

As an aside, I've tried looking up file sizes for 1-2-Switch, and found that it was about 1.3GB. However I couldn't find if that file size was the size of the ROM file on the cartridge, the space that the game takes up on the Switch's memory when it's installed from a cartridge, or the size of the eShop download. And either way, just as with the ROM size of Axiom Verge, knowing the ROM size would only tell us what the smallest chip capacity could be, not necessarily what was actually used. As such, I'm currently disregarding that piece of data for now. If we can find the part number of the Macronix chip used in some copies of the game, that will give us exactly the information we need.

 

How we know what we know about all the other chips

There are datasheets out there for the MR20RG2410D, MX23J8GL0, MR20RG4410E, MX23J16GL0, MX23J32GL0, MX23K64GL0, MX23K128GL0, and MX23K256GL0. These datasheets contain all sorts of technical data, including their capacities and package types. The MR20RG5410E was shown in a Spawn Wave video where he did a teardown of a 32GB game. So based on that video we got visual confirmation of the part number and the fact that it's in an LGA package, and the capacity comes from the fact that it's a 32GB game. Its part number is also consistent with the part numbers seen on other Lapis chips, so it's a pretty safe bet that it's a Lapis chip.

I didn't end up including that game in my spreadsheet data, however, because he never showed a close-up shot of the stamp code. I sent Spawn Wave a tweet and a YouTube comment asking if he'd be able to tell me the stamp code on the back of that cartridge, but I have yet to receive a reply. Hopefully he'll get back to me with that code, which if I'm correct should have an X for the 8th character.

One last note regarding the part number of the Lapis chips: you'll notice that I have all of them listed with an M as the first character, but when you look at the chips themselves, R is the first character. This is because the two datasheets for the Lapis chips list them as starting with an M; so since the manufacturer says that their part numbers start with an M, that's what I'm using. It's not uncommon for the stamps on chips to be abbreviated in some way to save space, and I'm assuming that's why they dropped the M on the chip stamps.

Contents Install Tool

In June 2019, an eBay auction was listed for three supposedly writeable Switch cartridges. The labels on the front indicated they were Not For Resale demo cartridges. They indicated sequential part numbers — 107462, 107463, and 108024 — with each cartridge respectively marked as V2, V3, and V4. These labels also bore the product code HAC-RTL.

 

Spoiler

Labels on front of cartridges showing "Not For Resale", "Demo", part numbers, version numbers, and product codes

 

The seller apparently lifted these labels off, revealing another label underneath. These labels more closely resemble standard Switch cartridge labels, and showed the name "Contents Install Tool". These had still different part numbers, with the only cartridge shown being 106669. They also show standard-format product codes, with some notable differences to what we normally see:

   

Spoiler

Front label underneath the top white label, revealing the name "Contents Install Tool", part number, and product code

 

While every retail cartridge we see begins its product code with LA-H, the product code on these begin with LB-H. They bear a USA region code, and the build character is A. Curiously, the game type character is a 1, rather than the A or B that we normally see on retail cartridges. The product identifier is CGN. These five characters are also repeated in the stamp codes, as we would expect.

 

Spoiler

Backs of the Contents Install Tool cartridges, revealing the stamp codes and LGA chip packages

 

The stamp codes are, curiously, 14 characters, rather than the 11 characters we've seen on all retail cartridges. The codes are:

• 1CGNAU0639X001
• 1CGNAU0889X002
• 1CGNAU1166X003

The first five characters match the five characters seen in the product code, same as with normal retail stamp codes. After that is a U, and it's unknown what that would denote. After that is four numbers, which do not seem to relate to the part numbers seen on either of the two types of front labels in any way. The fact that it's four numbers rather than the two we see in retail stamp codes is curious. After that is an X, which would be consistent with a Lapis-brand LGA chip. The stamp codes end with what would seem to be revision numbers, which do not match the version numbers seen on the top white label, but do follow the sequence. (V2 = 001, V3 = 002, and V4 = 003)

Nothing else is currently known about these cartridges, however the differences are quite interesting, and the 1 at the start of the stamp codes would seem to corroborate that the first character is the "game type" as speculated at the beginning of this post.

 

Conclusion

So, in summary, this is what we've got so far for the standard 11-character stamp codes:

ABBBCDEFGGG

• A = Proooooobably the game type, with A and B seemingly denoting retail releases.
• B = Product identifier, unique for each game. Can be any combination of numbers and/or letters.
• C = Build. Consists of a letter, with the initial build normally being A. Although every build is essentially the same game, different builds have some difference between them. These differences may be pre-patched ROMs, languages, inclusion of DLC, or other exclusive changes or content. However, sometimes the differences aren't that significant at all, and may merely indicate a different publisher being involved in the release. A notable example of different builds is the standard release of Breath of the Wild and the Japanese-exclusive Breath of the Wild + Expansion Pass, which features the latest game version along with all the DLC on the cartridge ROM.
• D = Unknown. Consists of a number between 0 and 4. Possibly related to manufacture site, possibly batch numbering, most likely not manufacture date, and definitely not region or language.
• E = Unknown. Consists of a number between 0 and 9, but haven't seen a 5 or 6. Possibly related to manufacture site, possibly batch numbering, most likely not manufacture date, and definitely not region or language.
• F = Probably ROM chip manufacturer, definitely ROM chip package type.
  • A = LGA / Macronix
  • B = TSOP / Macronix
  • S = LGA / Unknown
  • X = LGA / Lapis
  • Y = TSOP / Lapis
• G = ROM Revision number. Corresponds to software versions. Usually (but not always) the initial release is 000, and is incremented by 1 with each ROM revision.

I'll update this post as we get more data in and narrow things down further.

Edited May 12, 2023 by re4mat

[Fleck586 | 300]

This community never ceases to amaze me. That's a ton of work you put in. Well done!

[RH | 4,903]

First off, wow.  That is a lot of serious data collection and analysis.   I tried to read through most of it but I might have missed some details.

However, I think to fill in the gaps, you need to look at past Nintendo behavior and realizes that processes and IDs will change, but I highly doubt Nintendo would drop types of info they save in their various codes.  With that said, going back all the way to the NES, Nintendo has been stamping game carts with manufacturing facility/line IDs and game ROM versions.  This continued on through GBA/N64 era and I haven’t looked enough into the DS/3DS stamps, but I’d be surprised if they dropped stamping those details on those carts because this is important QA information.

I say that to say, simply, I’m quite sure that of all these IDs, certainly part of the stamp is the manufacturing facility or line.  Again, this is important to know because if a few broken games ship to customers, these IDs quickly allow Nintendo QA to potentially know where to go, down to a specific manufacturing line, to look for issues or maybe even broke equipment.

I know you mentioned all of these points, but I think I’d definitely start from the point of asking not if there is a facility ID or ROM but WHAT are the facility/ROM IDs?

I think you are on the right track with characters 7 and 8 being the facility.  If history is any indication, these digits are a bit ransom and to my knowledge we’ve never nailed down any facilities to specific IDs.  However, certain IDs were more common than others.  For instance, a lot of GB games are stamped with 22.  This was likely the primary production line.

Fast forward today and I’m sure Nintendo has probably refined their ID process, but certainly the same data is there. My guess would be that the 7 & 8 digits ID a facility/facility line and there’s a chance that the 9th digit does too.  The reason why digit #9 might align with specific chips is because chips used might be semi-locally sourced.  Meaning, for facilities in Japan, it’s easier to get one brand of chip than it might be in Taiwan.  These IDs might be similar by minor coincidence, but there is a correlation.

Also regarding ROM IDs, so bet the last three digits are for the ROM.  However, this might be a bit more free form.  Some games have specific builds per language, while other games have only 1-2 ROMs and you select the language on boot up.  Maybe the Switch is smart enough to detect the users region and auto-boots to a default language depending on the users account/IP address location of the Switch? That said, maybe the ROM version is a bit different from game to game and gleaning useful info might not be possible.  This could especially be true if developers define these build IDs as they release new builds to production throughout the life cycle of a game.

[re4mat | 65]

4 hours ago, Fleck586 said:

This community never ceases to amaze me. That's a ton of work you put in. Well done!

Thank you! That was about two weeks of work for just that one post!

 

2 hours ago, RH said:

However, I think to fill in the gaps, you need to look at past Nintendo behavior and realizes that processes and IDs will change, but I highly doubt Nintendo would drop types of info they save in their various codes.  With that said, going back all the way to the NES, Nintendo has been stamping game carts with manufacturing facility/line IDs and game ROM versions.  This continued on through GBA/N64 era and I haven’t looked enough into the DS/3DS stamps, but I’d be surprised if they dropped stamping those details on those carts because this is important QA information.

I think you're right. I did say above that "I'm going to assume that neither the 6th nor 7th characters are used to denote manufacturing site", but I think I worded that wrong. I actually do suspect that one of those characters is manufacturing site and another is batch number. So it's not that I'm assuming that one or both of those characters don't represent manufacturing site, but rather that I'm not assuming that they do. A subtle difference, but what I mean it is that we don't have enough information to know what it is, so by leaving it open we aren't closing ourselves off from other possibilities that may be revealed as we do get more information. Basically, I'm not ruling it out, I'm leaving it an open question. I'll edit and change that wording so that I'm more clear.

Also, that did give me an idea, which is to go back through the games on other consoles to see what their codes are for manufacture site, and see if there's anything we glean from that which may help figure that out.

 

2 hours ago, RH said:

I say that to say, simply, I’m quite sure that of all these IDs, certainly part of the stamp is the manufacturing facility or line.  Again, this is important to know because if a few broken games ship to customers, these IDs quickly allow Nintendo QA to potentially know where to go, down to a specific manufacturing line, to look for issues or maybe even broke equipment.

[...]

I know you mentioned all of these points, but I think I’d definitely start from the point of asking not if there is a facility ID or ROM but WHAT are the facility/ROM IDs?

I definitely agree. I think the purpose of these stamp codes is exactly that: to allow Nintendo to track  down any issues that may occur, from bugs in game code to manufacturing defects. It's been the perspective I've been approaching this from, and I think all the data in the stamp codes that has been decoded all would be things that Nintendo would find useful for accomplishing that.

For the other point, I believe that can be revealed with more data. We already seem to be narrowing down on ROM revisions, for example. But I just wish Nintendo were more open about where stuff is manufactured. I get why they aren't, but it sure would make my life easier! 

 

2 hours ago, RH said:

I think you are on the right track with characters 7 and 8 being the facility.  If history is any indication, these digits are a bit ransom and to my knowledge we’ve never nailed down any facilities to specific IDs.  However, certain IDs were more common than others.  For instance, a lot of GB games are stamped with 22.  This was likely the primary production line.

(6th and 7th characters, but who's counting? ) Yeah, I think this is true of the Switch, too. In the data I've collected so far, 13, 22, and 41 are the most common values for those characters. I still have my suspicion that one character is manufacture site and the other is batch number, but as I mentioned, it's also curious that those two characters only have appeared so far in 13 distinct combinations. 22 in particular does seem to appear a lot on Nintendo cartridges over the decades.

 

2 hours ago, RH said:

Fast forward today and I’m sure Nintendo has probably refined their ID process, but certainly the same data is there. My guess would be that the 7 & 8 digits ID a facility/facility line and there’s a chance that the 9th digit does too.  The reason why digit #9 might align with specific chips is because chips used might be semi-locally sourced.  Meaning, for facilities in Japan, it’s easier to get one brand of chip than it might be in Taiwan.  These IDs might be similar by minor coincidence, but there is a correlation.

My speculation is that the 8th character denotes package type and manufacturer because Nintendo already knows the capacities for the various chips they use, and the capacities used for each game are also something they'd know (likely on the purchase orders, for example, since Tom Happ sounded like he had been told what chip capacity his games would use, but had forgotten over time), and for each package type and manufacturer there's apparently only one chip used for each capacity. And since there would only be one combination of package type and manufacturer, and Nintendo already knows the capacity of the chips used in each game, having the package type and chip manufacturer on the stamp code would allow them to identify which part numbers are used in each game should the need arise to track that down, say in a manufacturing defect situation. Their main partner does seem to be Macronix, who designed the initial 16-pin LGA package. I remember reading a couple news reports to that effect, though I don't have them handy at the moment. They likely then lease those designs to other chip manufacturers as needed, including Lapis. Macronix is a Taiwanese company, while Lapis is a Japanese company, for what that's worth.

Also, there doesn't seem to be any correlation between chip used and the values for the 6th and 7th characters. This may change as more data comes in and gets plugged into the spreadsheet, but so far there doesn't appear to be any.

 

2 hours ago, RH said:

Also regarding ROM IDs, so bet the last three digits are for the ROM.  However, this might be a bit more free form.  Some games have specific builds per language, while other games have only 1-2 ROMs and you select the language on boot up.  Maybe the Switch is smart enough to detect the users region and auto-boots to a default language depending on the users account/IP address location of the Switch? That said, maybe the ROM version is a bit different from game to game and gleaning useful info might not be possible.  This could especially be true if developers define these build IDs as they release new builds to production throughout the life cycle of a game.

Yeah, they do have one character for build, and those build differences are sometimes (but not always) language. Anecdotally, the Switch does seem to be smart enough to detect the user's region and auto-boots the default language of the console if it's available. I'm really grateful that Nintendo decided to make the Switch region-free so that we can test things like this!

That page I found at the top of the post has LOADS of data regarding software version numbers and ROM revisions. The numbering seems to reset for new builds, so for example build A can have ROM revisions 000 and 001, and then build B can still have ROM revision 000, and that still indicates a different software version from build A's ROM revision 000.

[re4mat | 65]

Added my copy of Tears of the Kingdom to the spreadsheet. The 8th character package type is still consistent!

Edited May 21, 2023 by re4mat

[re4mat | 65]

Spawn Wave just released a video in which he opened up a copy of Tears of the Kingdom, and this time he showed the stamp code! (Which happens to have the exact same stamp code as my copy, interestingly enough.) Added it to the spreadsheet, giving us another data point for manufacturer and package type for the 8th character, and we've still got a 100% match for both package type and chip manufacturer. (Though we still need to get some B, S, and X stamp code cartridges opened up. Still no data on those!)

Edited May 22, 2023 by re4mat