Is SA-1 3.3v tolerant?

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

Moderator: Moderators

Post Reply
User avatar
Fisher
Posts: 1249
Joined: Sat Jul 04, 2015 9:58 am
Location: -29.794229 -55.795374

Is SA-1 3.3v tolerant?

Post by Fisher »

I have found no reference on this subject, so probably the answer is no, but I'm asking because I'm willing to buy a Portuguese translated repro of Super Mario RPG for my daughter.
She's learning how to read and got pretty addicted to this game when she saw it on the emulator.
I couldn't find any repro that's not made with a 3.3v ROM, but with the information I've got I think that any damage would be caused directly to the SA-1 Chip. Is that correct?
Unfortunately I just can't allow her to play every time on the PC with an emulator because my energy bill would become too big.
:-(

Also, I can't buy the parts and build one myself, because my EEPROM writer, wich is nothing else than an old motherboard, just can't write the proper ROMs, so I'm kind of screwed...

Thanks in advance.
User avatar
MaarioS
Posts: 149
Joined: Wed Jul 22, 2009 8:53 am

Re: Is SA-1 3.3v tolerant?

Post by MaarioS »

Well the answer is no, although you can always use voltage translation for the entire ROM chip. If you have basic soldering skills then I can help you get the proper ROM for an SA1 donor
lidnariq
Posts: 11432
Joined: Sun Apr 13, 2008 11:12 am

Re: Is SA-1 3.3v tolerant?

Post by lidnariq »

The bright side is that the SA-1's data bus is unidirectional: address comes from SA-1, goes into ROM, data comes out of ROM, goes into SA-1. So that makes the translation a little easier.

The SA-1, like the SNES, uses 5VCMOS thresholds, however. Even if one were to accept permanent damage to the SA-1's address bus drivers, 3.3V isn't reliably read as logic "1" by the SA-1.
calima
Posts: 1745
Joined: Tue Oct 06, 2015 10:16 am

Re: Is SA-1 3.3v tolerant?

Post by calima »

SD2SNES supports that chip, and with the SD2SNES Pro announced, the old sd2snes is -15%. You might also find one used, etc.
User avatar
Fisher
Posts: 1249
Joined: Sat Jul 04, 2015 9:58 am
Location: -29.794229 -55.795374

Re: Is SA-1 3.3v tolerant?

Post by Fisher »

Thanks for the answers.

@MaarioS to find a proper ROM would be nice, but I think my "programmer" won't help.
To build the level translators seems to be the most doable option, at least for now.
I have some soldering skills. Altough I don't think they're the best, I've done some repro "abominations" in he past and I would appreciate your help.

@lidnariq this would make me watch the SA-1 die slowly while having lots of crashes/lockdowns on the game. Potentially leading to a infuriated kid throwing the joystick out of the window.
While my beloved childhood console won't suffer no additional damage, the controller and both mine and the kid's patience wouldn't end unharmed. So, better avoid it.

@calima to have flash carts for my 3 beloved retro systems is a goal wich I'm unfortunatelly far to achieve. :-(
I have some hopes with the promisses of the new government to lower import taxes, specially for things not produced in my country, but that also leaves me with the absurd shipping prices.
So I'm not holding my breath for that.
User avatar
tokumaru
Posts: 12427
Joined: Sat Feb 12, 2005 9:43 pm
Location: Rio de Janeiro - Brazil

Re: Is SA-1 3.3v tolerant?

Post by tokumaru »

To add to the shipping problem: it seems that customs here in Brazil are doing things differently now... Instead of charging whatever they feel like in taxes, they're outright refusing packages that have any sort of problem. Just the other day I was checking if there were any updates on a retro gaming related item I bought and was surprised by the notice that the package was refused for not containing a description of the merchandise, and will be sent back to the seller. This is infuriating...

I was planning on buying more Everdrives from krikzz, but now I'm not sure I'm willing to take the risk of losing products if there's anything wrong with the packages...

Maybe the safer way now is to use a reshipping service, that gives us more control over the shipping details. Last time I used one of these services, I was able to specify the contents of the package myself.

Just when I thought they couldn't make importing things any more frustrating...
tepples
Posts: 22708
Joined: Sun Sep 19, 2004 11:12 pm
Location: NE Indiana, USA (NTSC)
Contact:

Re: Is SA-1 3.3v tolerant?

Post by tepples »

I imagine some countries have tightened up their customs enforcement in the face of duty evasion using "gift" and the like. But when I ordered from DealXtreme years ago, the package's contents were described as "video game accessory" with the correct value. Is a description of that sort insufficient?
User avatar
tokumaru
Posts: 12427
Joined: Sat Feb 12, 2005 9:43 pm
Location: Rio de Janeiro - Brazil

Re: Is SA-1 3.3v tolerant?

Post by tokumaru »

Yeah, for years people have tried to avoid taxes by marking everything as a "gift", being vague in the description of contents and lying about the cost of things. However, if something looked fishy, the customs would just charge whatever they felt like in taxes, which was annoying but at least we'd get our stuff most of the time.

I haven't seen the package that was addressed to me but was rejected by the customs, so I don't know how complete or how accurate the information written in it was, but from now on, everyone in Brazil should request sellers to be as accurate as possible when filling out the details about products being sent here.
User avatar
Fisher
Posts: 1249
Joined: Sat Jul 04, 2015 9:58 am
Location: -29.794229 -55.795374

Re: Is SA-1 3.3v tolerant?

Post by Fisher »

That's interesting!
Do you mind if I PM you for details when I can get enough money to do some imports?
User avatar
tokumaru
Posts: 12427
Joined: Sat Feb 12, 2005 9:43 pm
Location: Rio de Janeiro - Brazil

Re: Is SA-1 3.3v tolerant?

Post by tokumaru »

Fisher wrote:Do you mind if I PM you for details when I can get enough money to do some imports?
Not at all. My experiences buying from krikzz have been nothing but positive (I bought all of the following from him: Mega ED, SD2SNES, ED-64, ED N8 Famicom, Master ED, ED-GB), but my last purchase was probably about 4 years ago. Now that brazilian customs are returning packages, I'm a little apprehensive. I would probably reinforce that all information must be filled out as accurately as possible in the package, or use a re-shipping service where I can select the shipping method and fill out the details myself (which obviously makes things more expensive).
Markfrizb
Posts: 607
Joined: Sun Dec 02, 2012 8:17 am
Location: East Texas

Re: Is SA-1 3.3v tolerant?

Post by Markfrizb »

Hey Fisher,

I make a SA1 adapter pcb that uses the 5v 27c322 rom. It's clean and easy (no hand wiring). All fits inside the case. PM me for details if you're interested.
Post Reply