Any interest in 27c322 cart mod pcb's?

[Markfrizb]

It's four different 4 megabyte ROMs. You'd need four 27c322s to do it.

The version I have are 4 files, 2 meg roms. Would that version not work on real hardware or something?

That version is what was intended to work on real hardware and I believe it does based on the documentation on that website. It was the 4mB versions that is (still) in question as to whether it works 100% on a real cart.


Earlier in my video, I show the 2mB version running on my adapter.

[Markfrizb]

Yes, LoRom and 64kb SRAM





He's using a pic12F629 instead the binary counter 393, so you can manage the bankswitching more accurate.

Where are those wires going to in the back? Do you have a pic of it? Thanks

That's not my design so I don't know.

[Markfrizb]

The 4 megabyte versions are on the page too. No idea if they work on real hardware or not though.

I programmed the roms (x4) and mounted them to my adapter. The games all boot and cycle correctly. I'm not a Zelda player so if someone wants to test this cart for me, I'll send it to you.
MottZilla-- you interested? I'd like to determine if the 4mB x 4 version does work completely on real hardware so I'd like it to be tested ASAP.

I'll post a video soon of my progress and tests.

Thanks

Edit: http://youtu.be/-23aKVsDc64

Id be interested in trying it out.

PM me your address. I'll post it to you (assuming you're in the USA).

Thanks

[josete2k]

Yes, LoRom and 64kb SRAM

He's using a pic12F629 instead the binary counter 393, so you can manage the bankswitching more accurate.

Where are those wires going to in the back? Do you have a pic of it? Thanks

It was a prototype for the AST board final design.


They are going to a 12F629... but this is the Markfrizb post, not mine.

[MottZilla]

I programmed the roms (x4) and mounted them to my adapter. The games all boot and cycle correctly. I'm not a Zelda player so if someone wants to test this cart for me, I'll send it to you.
MottZilla-- you interested? I'd like to determine if the 4mB x 4 version does work completely on real hardware so I'd like it to be tested ASAP.

I've never been very involved in the BS Zelda Ancient Stone Tablets game. I think it should work on a real SNES, but I'm not 100% sure.

[Markfrizb]

I mailed it to Tormentor for play testing.
Can hardly wait to see what he says.


Oh, in case anyone was wondering, the adapter I'm making should fit in a SFC case too...


Should get final set of boards in about 3 weeks

[josete2k]

I can confirm that AST is 100% working in real hardware, both versions 2mb and 4mb.

But there are little issues in saves when the battery outputs are lower than 3,2v. Maybe the sram patch isn't accurate.

[MottZilla]

The "patch" has nothing to do with what voltage the battery puts out. If saves have some tendency of being corrupt it could be caused by how the patch handles SRAM. For example if code somewhere corrupts or invalidates the save data, or if somehow you could interrupt the saving process leaving invalid data in place. I have no idea how the saving is programmed in their AST patch.

All the battery's job is to maintain enough power to keep the SRAM in its low-power retaining mode. If the battery voltage drops too low it will lose the data, the patch has nothing to do with it.

[josete2k]

Yes, but the time for battery switch is essential...

As a friend explained to me, maybe the sram data is placed too near to the beginning of memory and a slow battery switch could destroy some bits.

He made a custom pcb for that game and when using 70ns sram all data are lost, soon or later. All is working better (not perfectly) with 120ns sram...

This is because the -12 sram needs a lower power from battery to get the stand-by mode and in the switching time it keeps the data better than -70 do.

[whicker]

Yes, but the time for battery switch is essential...

As a friend explained to me, maybe the sram data is placed too near to the beginning of memory and a slow battery switch could destroy some bits.

He made a custom pcb for that game and when using 70ns sram all data are lost, soon or later. All is working better (not perfectly) with 120ns sram...

This is because the -12 sram needs a lower power from battery to get the stand-by mode and in the switching time it keeps the data better than -70 do.

Although I believe this is the case in your situation, the speed grade does not imply anything about how much quiescent current is uses. It depends on the series of chip, the manufacturer, the date of manufacture, etc. In other words, some SRAM chips were made to be more low power than others, independent of access speed. Certain series of SRAM chips also are safer to bring down to a lower voltage than others.

Good luck finding all this information nowadays. It isn't so organized, and a lot of stock is going to be pulls (used parts). Your best bet is anything that says Low Power SRAM, but even then it would help to consult the datasheet.

Also, SRAM doesn't lose data sequentially starting from the beginning. So there's no particular spot a number should be. It's just going to be random bit flips wherever, maybe in a certain pattern for that particular chip (most bits of certain rows or columns that would tend to go one way or the other), but mostly random if we're talking generalities across a lot of samples.

[Tormenter]

I mailed it to Tormentor for play testing.
Can hardly wait to see what he says.


Oh, in case anyone was wondering, the adapter I'm making should fit in a SFC case too...


Should get final set of boards in about 3 weeks

Im through week 1. Everything saved perfect, and week 2 loads as it is suppose to with week 1 save file =)

[qwertymodo]

If you're having issues with saves at lower voltages, something like this might work nicely. Wide operating voltage range, 2.7V-5.5V, nonvolatile so you wouldn't even need a battery.

[Tormenter]

Ive been testing out the Zelda AST for Mark. Everything works great. Saves switch over to the next week etc just like they are suppose to. I thought I had an issue at one point, but realized that the time for the week had ran out, so turned out to not be an issue at all, just slow game play on my part lol. Great work!!

[Markfrizb]

For anyone who might be interested, here is a video of the pcb in action. Shown is my final proto.
Production pcb's will be here approx end of month. Pcbs will have all necessary parts pre mounted. http://youtu.be/5SlZTrWcLw4

Here are previous vids of prior proto boards... Features are same, just design changed.


http://youtu.be/-23aKVsDc64

http://youtu.be/H0MvQ0-VDzc

http://youtu.be/eL5o8KmW21I

http://youtu.be/kca_JaNtx0E

Delivery update: June 26th is approx arrival date

Edit: boards have arrived!

[Markfrizb]

The pcb's have arrived. I've tested a random 10 and they work! So now I need to do a write up and a how-to-use it (although some of the videos will show some of that)

I am leaving for vacation tomorrow (Saturday) so I won't be able to ship until I get back. I have 200 pcb's total but I only plan on selling 100-150 of them.
Price is $15 each. The pcb's are ready to use as is. If you want socket strips, then add $1 for 4. It doesn't come with roms. Acquisition of the roms and programming will be your responsibility.

Please read previous posts on features and check out the videos also.
Thanks for reading! Email with questions or post to this forum.