The CIC & 10NES Explained

A brief history and technical deep dive into the Nintendo CIC and 10NES Lockout System.

References

Power Punch by 2050
Where by Tobias Bergson
The Chosen by Notize
Midnight Tokyo by Downtown Binary

Chapters:

0:00 Introduction
2:08 Motivations
6:29 Technical Details
12:16 Circumvention
18:04 Conclusion

CC Attributions

Modified via cropping and pan zooming for video effect

[NesHacker]

After two months I've finally finished! Hope you all enjoy exploring the CIC with me and make sure to check out the description for links to sources I used when making the video :)

[dastoddo]

I've read and viewed numerous explanations of the 10NES CIC subsystem. This is by far the best and clearest explanation. Also including the explanation of the Tengen Rabbit chip, the non-technical industry context, as well as the subtle differences in intellectual property protections used to cover the 10NES ties all of this info together in a masterfully crafted way.

This channel's videos not only beautifully explain subject matter, but present it with excellent video production quality that makes it a pleasure to watch. Keep up the excellent work! I really hope this channel takes off.

[scootergirl]

This is the best part of YouTube - people like this that go full geek on very specific areas that wouldn't be able to get a platform anywhere else because its so niche.

[fraserrisc]

Very clear description of the CIC lockout chip, especially considering the history, legal and technical aspects. Thanks!
I'll add that Nintendo really liked the 4-Bit Sharp "Micro-Computers" since they were used in the Game & Watch series all the way up to the N64's lockout chip the "PIF".

[_macrophage]

If Nintendo was so concerned about game quality, how the hell did LJN get a license??

[gwalla]

IIRC there was another way of circumventing the CIC: manufacturing the cartridge with a port for another cartridge (sort of like the Game Genie) so that the 10NES pins were connected to the new socket. To make this work, you would have to insert another game cart with a working CIC into the unlicensed game's socket. Since the 10NES system is entirely separate from the rest of the game cart circuitry (aside from power and ground rails), the NES itself could not detect this. As far as the lock could tell, it was communicating with a functional key and everything was groovy. This did make manufacturing more complicated, though, and also made it pretty obvious to the user that they were involved with Shenanigans, so I don't think it was used often. I think it was used by at least one unlicensed publisher, though.

[beastworm]

Despite that I knew the story and how it worked, I was glued to the screen watching the video. Great job!

[kirbylouise]

Amazing video!!

17:24 - IIRC It's the same idea as the modern day "USB Killer". In short:

- charge up an internal capacitor of the "evil CIC" using power from the host device
- once fully charged, send a super high voltage down a specific pin to the lock chip (Too much voltage can be very harmful to electronics on the receiving end as voltage is basically electrical pressure, thanks Schoolhouse Rock!)
- Lock chip puts out magic smoke and can no longer reset the NES
- Freedom!

There is a downside to this method though - Attempting to use the trick on a system without the 10NES will end up bricking it (this even happened in an episode of AVGN where his top loader NES was killed by one of those carts!)

The best way today to disable the 10NES is simply to open up the console and cut pin 4 of the lock chip. Unfortunately the NES uses an inverted motherboard so it's a little more work than just removing the case and cartridge housing, but iFixit has a step-by-step teardown you can follow and there's no soldered controllers like the Famicom

[DemureDave]

Great job on this! This was definitely worth the wait!

[chrisd]

This is the best technical explanation of 10NES I've ever seen. Definitely cleared a few things up for me. Thanks Ne Shacker!

[Gamers_of_Oz]

Thankyou for your work man I look forward to your next video keep them coming strong

[mbh]

I just recently discovered your channel and absolutely love what you’re doing. As a gamer that first started with the NES I find it fascinating to learn about the hardware and how everything worked. I hope to see more great content in the future. -New subscriber

[dark_larva]

Thanks for your work. I stumbled into your channel randomly and love the content you put out. I also really like the Power Punch song so thank you for linking the song in your credits.

[Martial_Monkey]

Outstanding work, dude. You must keep posting those videos. I love them.
I'm developing a 6502 emulator. Sometimes I get stuck, and watch your videos. Helps a lot.

[ReverendTed]

Wonderful explanation! The only thing missing from this video is the "Nintendo Seal of Quality". (Except for being visible on the game boxes in the background.)

[lostrocket]

Thank you for your channel, it's a treasure among YT channels!

[LorenHelgeson]

From what I've heard, part of what clinched the lawsuit against ATARI was that they just lifted the CIC code wholesale, including a bunch of code that was commented out, legacy code that was not even being used by the CIC at the time. So, I don't think "up to the task" was the issue there. Their developers were just being extremely lazy, and I can imagine those who said "we can't do it" were promptly fired as part of the blowback for losing the lawsuit.

One thing I've learned over the past 20 years as a web developer is that when you bang your head against the wall for hours trying to figure something out, and the solution is then magically presented to you by someone else who DID actually figure it out, you sure as hell better take the time to figure out how they did it. ATARI's devs failing even that, I'm sure that with just a cursory scan of the CIC source code, the commented segments would stick out like a sore thumb.

[flibidydibidy]

This is very well put together and a great video! Awesome job :-)

[jimmymkirk]

In the court case, Atari cited the chip shortages leading to low game yields which made their ROI artificially low. Atari originally asked if they could make their own chips before getting the code directly from the Copyright office.

[davecool]

Great video! I was hoping for the explanation of the voltage spike disable though... it's the one I never understood. Can't wait for your next video.