The Super Nintendo Cartridges (2024)

FABIEN SANGLARD'S WEBSITE CONTACT RSS DONATE April 21, 2024 Inside the Super Nintendo cartridges table.lined , table.lined th, table.lined td { border: 1px solid black; border-collapse: collapse; } table.lined td { padding-right: 1ch; padding-top: 0.8ch; padding-bottom: 0.8ch; text-align: right; } table.lined th { font-weight: bold; background-color: #BBB; } blockquote { background-color: #f3f3f3; border: dashed 1px grey; width: 97.5%; font-style: italic; text-align: justify; padding: 1ch; padding-top: 2ch; padding-bottom: 2ch; margin : 0ch; margin-bottom: 2ch; margin-top: 0ch; } blockquote div { text-transform: none; text-align: right; width: 100%; } iframe { width:100%; /* height: auto;*/ margin-bottom: 2ch; } } One of the remarkable characteristics of the Super Nintendo was the ability for game cartridges (cart) to pack more than instructions and assets into ROM chips. If we open and look at the PCBs, we can find inside things like the CIC copy protection chip, SRAM, and even "enhancement processors". CICThe copy-protection mechanism of the SNES is something I already dig into in my 10NES article. It works by having two chips talking in lockstep. One chip is in the console, the other in the cart. If the console CIC sees something it does not like, it resets every processor. Not every SNES cart has a CIC. Unsanctioned games such as "Super 3D Noah's Ark" don't have one. To play the game, one needs to first insert the game in the console and then plug an official cartridge on top. The CIC bus lines are forwarded from Noah's towards the official game's CIC! ROM: instructions & assetsI was unable to find a list of all SNES games with their ROM size. So I made my own. That is 3,378 titles (across USA/Japan/Europe) presented in the chart below. Games ROM size used to be expressed in bits instead of bytes. Zelda III, for example, was not advertised as 1,048,576 bytes but the size of its ROM in bits, that is 1,048,576 * 8 / (1024*1024) = 8Mb. The largest game ever released was Star Ocean (48Mb or 6,291,456 bytes) while a masterpiece such as Super Mario World used a mere 524,288 bytes (4Mb) ROM. If you don't want to click on the .csv, here are the most noteworthy games (feel free to scream me an email if your favorite game is not in the list). Game Zone Mb Bytes Star Ocean Japan 48 6,291,456 Tales of Phantasia Japan 48 6,291,456 Street Fighter Alpha 2 USA 32 4,194,304 Street Fighter Zero 2 USA 32 4,194,304 Chrono Trigger USA 32 4,194,304 Super Street Fighter II USA 32 4,194,304 Donkey Kong Country USA 32 4,194,304 Super Metroid USA 24 1,571,143 Secret of Mana USA 16 2,097,152 Street Fighter II USA 16 2,097,152 Super Mario World 2 - Yoshi's Island USA 16 2,097,152 Mega Man X2 USA 12 1,572,864 Aladdin USA 8 1,048,576 Teenage Mutant Ninja Turtles IV USA 8 1,048,576 Contra III - The Alien Wars USA 8 1,048,576 Legend of Zelda, The - A Link to the Past USA 8 1,048,576 Star Fox USA 8 1,048,576 Super Mario Kart USA 4 524,288 Super Mario World USA 4 524,288 F-Zero USA 4 524,288 SRAMSome titles offered the ability to save progress. This was done by having a SRAM chip powered by a battery. The SRAM went into low-power mode when the console was turned off to reduce the drain. Source (snescentral.com). Zelda III PCB In this Zelda III PCB above, we find the CIC (D413A) mentioned previously in U4. In U1, 0x80000 = 524,288 bytes of ROM. In U2, a LH5268AF-10TLL, 64 Kbits (8 KiB) of SRAM. In U3 the MAD-1 chip is a Memory Address Decoder which arbitrates access…

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