Riff Box2 not detect any EMMC.

[Enforce]

Hello guys, I have the same problem ( Unlock Forum - RIFF Box support forum ) - riff 2 does not detect ANY emmc, when it is on motherboard. I've try detect simple SD card, everething works ok, riff detect it without problems.

Also, the same emmc chip onboard can be read and to be written a simple card reader.

Thus, it turns out that an ordinary card reader is better than a professional Riff box?
I specifically bought the Riff box, as not all emmc chips are readable by a simple card reader, but in this case, the Riff was completely useless.

Maybe I'm doing something wrong? Tell me possible solutions to this problem. I need to read emmc when it is soldered on the motherboard.

I try to work here with these emmc

(Micron) MTFC4GACAANA-4M IT and similar

[Legija]

Hi,
Problem is well known and there is a fix, it involves either building clk line driver or box modification, which ever is easier for you.


It turned out that direction autosensing I/O buffers wont work properly if there is pull-up resistor on target device board, even if advised it should by TI


So, since CLK bus is routed through U7 buffer and R80, it needs to be either amplified or rerouted though uni-directional buffer.
Bellow you have box modification which will reroute CLK via uni-directional buffer and use unused block on JTAG side.


Or, you can build simple driver circuit with any of two buffer chips from schematics in PDF.

[Enforce]

Thanks.


Ok, I did all the modifications on the riff box2 board, removed the resistor R80, added the missing connections and cut a couple of tracks.

Now nothing works at all, even a simple SD card is no longer detected.
Why??? I did everything in full accordance with the attached picture.

[Legija]

You most probably did something wrong.


Please make photo of U3 area and upload here.

[Enforce]

I carefully examined the board and found a short circuit between pins 13 and 14 on U3.
They are very tiny and I could not immediately see it.

At the moment, the short circuit has been fixed and oh, miracle, riff 2 is working again and now I can read emmc directly on the target board! ( I just checked it.)

Thank you so much for your help!

[Legija]

Ok, great to see it works now.


Customer is always right, even if wrong . . .