Hardware Card Reader required for Hardmod and Explanation

[kaemacintosh]

Hi guys,

I've looked far and wide but seemingly have tried most all of my sd card readers for hard modding an o3DS with no success. I've tried 7 different readers (An HP Printer, 3 Laptops, a Desktop, and two usb 2.0 adapters) and none of them work.

1. I wanted to know what my options are for these readers and specifically why there are those that work and don't. Is it even the SD portion of the spec. that matters here? Or should I be looking only MMC supported types, due to the embedded-MMC in the 3DS.
2. All of my computers are on Windows 10, and some show the 3DS eMMC unit as a drive upon SD Card insertion - however with no media in it. Others simply don't get to this stage at all. Why is this? Is it the OS? Is the speed on these chips, to keep up with the 3DS clock? Is it a special type of mode? And is there a name for such in a spec.? WinDiskImg32 issue?
   
3. I do have a raspberry pi 2 (model B) and Arduino Uno, and wanted to know if the GPIO pins or similar is duable without purchase of a separate adapter for NAND Dumping/Writing. There was a similar-ish process for the gateway unlocking of a locked eMMC controller, but required a different solder point or two on an XL unit and I don't believe was used for dumping. In-all here, is this possible on one of these units?
   
4. Does length of the wires actually matter for interference coming from the board to the SD Adapter? Someone said they had a total of no more than 15 cm, or ~5in. and I just trimmed my down for safety.
5. The main hardmod guide referenced taking out the SD Reader from USB power for boot into the blue dump screen. Then plugging it in. I've noticed however, that I get a different "error code" on the 3DS depending on the card reader I use. Is there a "correct" error code I should see? Additionally is there a handshake of some sort that limits me to that adapter, or disconnects operation entirely when unplugged from the reader (while the blue dump screen has been presented). I'm assuming not, as its a controller, but I don't know what information is exchanged or even what actual spec. is being used; Another way of putting this: boot with Reader#1 -> plug into other reader (that has power) -> dump. Is that possible/ideal?

I've done as extensive a search on all of this on gbatemp but keep coming up short with scattered posts, some varying with their credibility/legitimacy. Any help/info would be appreciated, even if you only know a certain part, please feel free to list experiences, but please keep this on topic if conversation continues.

Thanks!!!

 

[vb_encryption_vb]

If it appears and disappers its your soldering. O3ds.will.work with just about any reader.

 

[kaemacintosh]

If it appears and disappers its your soldering. O3ds.will.work with just about any reader.

It doesn't disappear and the reappear however, and that also contradicts the list that's on the subsection about confirmed supported readers.

 

[vb_encryption_vb]

It dont really contradict anything. Whats listed has simply been confirmed is all. If it has appeared one time as you previously stated, than its a soldering issue.

 

[kaemacintosh]

It dont really contradict anything. Whats listed has simply been confirmed is all. If it has appeared one time as you previously stated, than its a soldering issue.

What I mean specifically, is that the SD Reader shows up as a card was inserted (on three of the seven units), however it says no media (on two of those three) and doesn't give me an option to format in disk manager, again, says there's no media inserted. It's never appeared on any of my readers to format or that there was an actual media. My hp printer said there was an error and to eject however. I don't know what that translates to however - whether the reader just isn't supported or what. Because I am only using Power, Ground, Clk, and a Data line. So if it boots into the boot screen to begin with, that, to me implies my lines are proper (at least three of them - maybe one of the power lines but no more; unless the clock is directly fed into data on boot) based on those labels given to the pins

 

[vb_encryption_vb]

Chances are its the clk point.

 

[shipwreck5]

there is no power line. there are only clk, cmd, ground, and the data lines. The power is received from the battery of the 3ds. also u should power off the 3ds then insert the adapter into the reader then turn on the 3ds (u should get a blue screen with an error code) then plug the reader into ur pc. that should work.

 

[kaemacintosh]

Got out my multimeter to test the pins, and indeed, it was a pin mismatch on the VSS1 line on the microSD card converter, which would account for the mismatches/improper operation. The others all checked out. I incorrectly assumed that all were good based on the blue boot screen. Thanks for the corrected direction.

Chances are its the clk point.

Turned out to be the positive rail to the microSD card adapter. I'm successfully dumping now. Clk I was sure to get right, as it was the hardest one. The other connections were easy as pi.

there is no power line. there are only clk, cmd, ground, and the data lines. The power is received from the battery of the 3ds. also u should power off the 3ds then insert the adapter into the reader then turn on the 3ds (u should get a blue screen with an error code) then plug the reader into ur pc. that should work.

VSS1 is the power line. Its the shared positive signal. This is needed to 'share', if you will, a power source between multiple devices for correct operation on the clock signal. Ground being the other power line.

 

[shipwreck5]

ur right vss needs to be same for all devices for it to work but it isn't power its ground. vcc is power.

 

[kaemacintosh]

ur right vss needs to be same for all devices for it to work but it isn't power its ground. vcc is power.

VSS being the ground for the system components. Regular Ground being at a different voltage from VSS. Power lines in reference to the two main lines for voltage reference in the system. So yes, why they are still both ground in their respects, they are two separate lines for power transfer. VSS is not VCC, but in this case it serves as such for these four wires, otherwise a different wire/solder point wouldn't be needed.