Help on level shifting with resistors

Discuss hardware-related topics, such as development cartridges, CopyNES, PowerPak, EPROMs, or whatever.

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koitsu
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Re: Help on level shifting with resistors

Post by koitsu »

Fisher wrote:Interestingly the guy claims to have the SNES datasheet, and that it states clearly that all components are totally 3.3v tolerant.
I asked him a link to see it by myself!!
To my knowledge (read: I could certainly be wrong), the actual "SNES datasheet" has never been leaked. There's been a lot of stuff leaked over the years (ex. several versions/revisions of the SNES developers manual, all from different years), but not an official schematic or operating spec datasheet. There would be no reason for Nintendo to ever give this out (to developers), as official cartridges were always handled by them. There are some general block flow diagrams in the official manual, but those are for understanding how the ICs/pieces work together and what busses are for what, not electrical specifications. So, I too am going to on out on a limb stating that guy is full of BS.

It's funny, this exact type of attitude/approach (people hiding behind lies, and getting very aggressive if someone questions their products) also used to happen in the early 90s during the SNES copier days. Everyone in the "scene" (esp. hardware-wise) was aggressive about protecting whatever it was they were selling, because otherwise it could cost them money. Different copier vendors (distributors, often Chinese) would try to slander the other with false claims, like "blah blah copier can actually fry your console!" and so on. Most users buying copiers didn't know truth from lies, so it became a stupid "sub-scene" battle. I see something similar in fashion happening here, where people selling repro carts aren't complying with proper voltages and aggressively justifying their stance by saying "well it works, so what's the problem?" followed by any other lie they can come up with else they risk their products not selling.

It's so much easier to just be truthful and then start releasing new versions that have level shifters in place, you know? "The old versions should work, but if you're really worried, I will replace the product with the newer version with level shifters, just send me the old ones and I'll send you the updated model" would be wise, and set a good precedent too. Customers like that.
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Fisher
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Re: Help on level shifting with resistors

Post by Fisher »

koitsu wrote:the actual "SNES datasheet" has never been leaked
That's exactly what I was suspecting.
Thanks to the confirmation.
Also, I think if someone like you, that has been on the "scene" from years, don't know about such a thing I think the chances of it doesn't exist is around 99%.
koitsu wrote:It's funny, this exact type of attitude/approach
Unfortunatelly this kind of behaviour is sort of common here. :-(
I remember a problem I had with a PS2 chip, the ThunderPro, it was more or less like this...
Just that time I was a paying customer instead of just a questioner.
Sincerelly... I'm not addicted to alcohol, but lately I just wanted to get some botles of cachaça and put down my throat to see if I can get some relief!

I'll (try to) politelly expose this to the guy and invite him to discuss here.
Again, many thanks for the information!

Edit:
@Ziggy587, sorry, I totally missed your post. :-(
I'm more or less on the same boat as you and share your vision (or should I say opinion or knowledge?).
Basicaly, don't use nothing is bad, resistors are better and level shifters are perfect.
Ziggy587
“Well, my device has been working properly for 2 years now." This is like saying, “I’ve been smoking for 2 years and I don’t have cancer. Therefore, smoking does not cause cancer.”

I used this same example. :-)
Unfortunatelly my SNES was damaged with about 8 months of intense use, if playing an average of 15h/day can be considered this.

Also, the guy stated a total disbelief that I got a friend who was going to US and got the console reviewed there, but belives in an information that is 99% fake or inexistent. :|
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