Disabling NES lock-out chip question

[Prodos8]

I was bored this evening so I decided to disable the lock-out chip in my NES by tying its pin 4 to ground. After successfully snipping the pin with a small set of scissors, I tried to bend the pin up. However, I over bent it and the pin snapped clean off the IC, so now there no way to ground it, short of soldering in a new IC. My NES still powers up and plays games, and doesn't blink, even with no cartridge in.

 

My question is how critical is grounding this pin? Since mine isn't grounded is there some sort of problem that may develop?

 

Any advice/insight would be appreciated.

[keilbaca]

I was bored this evening so I decided to disable the lock-out chip in my NES by tying its pin 4 to ground.  After successfully snipping the pin with a small set of scissors, I tried to bend the pin up.  However, I over bent it and the pin snapped clean off the IC, so now there no way to ground it, short of soldering in a new IC.  My NES still powers up and plays games, and doesn't blink, even with no cartridge in. 

 

My question is how critical is grounding this pin?  Since mine isn't grounded is there some sort of problem that may develop?

 

Any advice/insight would be appreciated.

1006413[/snapback]

 

absolutely none.

 

Mine isn't grounded, yet plays every PAL and japanese game fine.

 

You have nothing to worry about, unless you want to play the ever rare silver and gold NES championship cartridges

[Shawn]

Your fine, It doesn't really need to be grounded and you will find you will not get the "blink" from Euro or Japan games anymore, Well worth the pin being cliped. Only problem I have ever heard (but not expericnced myself ever) was that the lockout chip runs some sort of timing for certain games, but like I said I never encoutered a problem once and I used to have a mighty selection of NES games. So ya, your good to go with no worries.

[Prodos8]

Ok...thanks...guess I'll just let it be then.

[Atariman]

would this also get rid of the annoying blinking I get whenever I use the famicom->nes adapter along with the game genie and famicom disk drive? It seems like I have to press the reset button about a thousand times to get the whole combination to power up sometimes...

[keilbaca]

would this also get rid of the annoying blinking I get whenever I use the famicom->nes adapter along with the game genie and famicom disk drive?  It seems like I have to press the reset button about a thousand times to get the whole combination to power up sometimes...

1010442[/snapback]

 

Most definitely

[Jagasian]

The lockout chip is the enemy within your NES. What exactly does the NWC cart need from the lockout chip, for the cart to run correctly? Just in case I ever get my hands on a NWC cart and all

[keilbaca]

The lockout chip is the enemy within your NES.  What exactly does the NWC cart need from the lockout chip, for the cart to run correctly?  Just in case I ever get my hands on a NWC cart and all

1010466[/snapback]

 

Its actually used to fully unlock the game, its intergraded into part of the ROM. If it can't talk to it, it won't play at all.

[Bruce Tomlin]

ts actually used to fully unlock the game, its integrated into part of the ROM. If it can't talk to it, it won't play at all.

That's tricky. I guess it might have the signal from the cartridge CIC chip going into the mapper or some such to disable part of the ROM. Does it have any problem running on an emulator? Are there any other games that do this?

[russdog]

What's the name of that game that you all are talking about that needs the lockout chip? That concerns me, being that the top-loading NES and the Famicom have no lockout chip, and that I usually completely remove the lockout chip from my NES systems (maybe it's just me but I think it's silly to cut up and leave in a "disabled" chip in the machine when you can simply remove it and add 2 little wires to keep the reset button functional). I do a lot of electronic work as a hobby, and at school too (I'm taking electrical engineering courses). I'd like to find a copy of any cartridge that requires the lockout chip and try to figure out a way to make it not need it. If I remember correctly, the NES board runs a 4MHz clock reference to the lockout chip in the cartridge - I wonder if this is what is needed.

[chadtower]

It's the NWC cart that has about 15 known copies and costs well over a thousand dollars. Don't worry about it, you'll never see one.

[david.winter]

Like others said I too confim that I have long since cut pin 4 on most of my NES consoles (that was back in the late 1990s) and I never had any problem running games from the US, Europe, Japan, etc.

 

I would never ground it because you do not know what signal goes to it. Suppose there's a +5V signal coming to a grounded pin: you get a short circuit which can have no incidence on very fast signals, but which can easily destroy a chip when they stay up too long. This is why in many cases we use a pull-down resistor to limit the current and avoid problems.

[Artlover]

What's the name of that game that you all are talking about that needs the lockout chip?

http://www.atarihq.com/tsr/nes/nwc/nwc.html

[DrLove0378]

Phew. Now I don't feel so bad about clipping my lockout chip.

 

 

Off-topic: I wonder if a reproduction of the World Championship cart is possible? (I'm leaning towards no, due to its unique board and all, but someone out there might know more about it than I do. But methinks no one's going to open theirs up and find out.)

[SignGuy81]

Like others said I too confim that I have long since cut pin 4 on most of my NES consoles (that was back in the late 1990s) and I never had any problem running games from the US, Europe, Japan, etc.

 

I would never ground it because you do not know what signal goes to it. Suppose there's a +5V signal coming to a grounded pin: you get a short circuit which can have no incidence on very fast signals, but which can easily destroy a chip when they stay up too long. This is why in many cases we use a pull-down resistor to limit the current and avoid problems.

 

 

I know this is a very old topic but I was just researching this topic about the NWC and very curious about the fact that the game requires a lockout chip. As far as what you are talking about supposing a +5V signal coming to a grounded pin, that would not be an issue as it isn't going to happen. Suppose a 0V signal was coming to that pin when it was tied to 5V. It wasn't going to happen in either case. That would not be an issue as it is an input pin, not an output pin. And it should be tied to ground because inputs can float high or low when left unhooked and we want to make sure it stays low. It does appear though that in almost every case that this pin on the chip always floats low however, but I would still tie it to ground anyway.

 

That being said however knowing that there may be a select few games that actually require the lockout chip, even knowing that I would probably never run across one, I might instead would install a SPDT on the back of the console to select between ground(disable) and +5V(enable) on pin 4, just in case some rare instance I somehow come across that game.

 

And also since the NWC ROM itself requires the lockout chip that also means if you had the game ROM in a flachcart it still should not work without a lockout chip or if the lockout chip is disabled. So therefore I believe I will go with the the switch to enable/disable the lockout chip on the back.

[SignGuy81]

Like others said I too confim that I have long since cut pin 4 on most of my NES consoles (that was back in the late 1990s) and I never had any problem running games from the US, Europe, Japan, etc.

 

I would never ground it because you do not know what signal goes to it. Suppose there's a +5V signal coming to a grounded pin: you get a short circuit which can have no incidence on very fast signals, but which can easily destroy a chip when they stay up too long. This is why in many cases we use a pull-down resistor to limit the current and avoid problems.

 

 

Also that isn't why we use a pull-up or pull-down resistor. I mentioned above using a SPDT switch to switch between ground or 5V on input pin 4 of the chip. I could instead tie a lets say 4.7k ohm resistor or so from pin 4 to ground, and instead use a SPST switch for enabling the lockout chip, when the switch is off the pin is tied low via the pull-down resistor. It being a high resistor value when switch is on there is no problem with short between 5V and ground. That is why pull up or pull down resistors are used. There is no problem tying ground directly to an input, or 5V(for a chip designed to take 5V logic signals) just as long as you don't try to tie both together.

Edited May 23, 2017 by SignGuy81

[scotty]

Off-topic: I wonder if a reproduction of the World Championship cart is possible? (I'm leaning towards no, due to its unique board and all, but someone out there might know more about it than I do. But methinks no one's going to open theirs up and find out.)

The rom has been dumped. I have it, so I do not see a problem why it should not work. Works fine under Nestopia. I do not have my EverDrive N8 yet, but I do not see why it would not work on there either.