x360ace + Dual NAND

Never mind. Already desoldered NAND again resoldered post to FT6U1, restored track, and tried files.
I'm a bit puzzled ad they all seem to boot I cant seem to tell difference. But my NAND has currently has retail image, does that make any difference?

 

Its just that in my previous attempt with dual-nand even the retail image would not boot....

OK, but back to testing Here is what I did:
- resoldered the NAND flashing wires, read back the retail nand, checked that it worked.
- created a rgh2 image with j-runner dash 17150, cr4 not checked. Should I changed some ECC or not (well I didnt)? Flashed it and verified
- left the post wire to FT6U1 and checked the three files you uploaded once more. - Now none of them worked.

 

so JA_L_0.5_T_59.7.xsvf also "worked" with retail nand?
yes

This time waited longer
E8 didnt start for 5min
E7 worked, but the boot took couple of minutes (didnt measure) at first attempt and 1 min 45 sec at second.

 

I feel unqualified to answer, I'm uploading a video so you can see (will take time).
From what I see 90% video consists of Short-Short-Long triplets up until very end where its like two shorts followed by 3 quick shorts and bootup.

Video here:

 

are they still for FT6U1?

 

E4 and E5 both boot
E6, E7 dont, not even once.

E5 is a bit more consistent than E4 which in one occasion hung.

E5: 44 sec, 8 sec, 22 sec, 50 sec, 8 sec, 1m 27, 58 sec
E4: 2 min, 10 sec, 17 sec, 1m 22, hanged, 16 sec

Times are approximate and measured by eye on phone.

 

E4 works really well: 7s, 7s,7s,7s, 7s,15s
E5 works worse: 20s, 36s, no boot(over 3min),15s, 36s

 

Resoldered NAND on bottom side.
Connected button, ce1, ce2, smc on top side, removed nand track patch.
Checked that both nands can be read successfully.
Started up with the same E4 image - no successful startup (5 min limit).
Tried to start from second nand - same.
OK, wrote retail image to motherboard NAND and verified it re-read successfully.
Tried to boot from that it tried to glitch 4-5 times after that RROD displayed. Cant really retrieve secondary code, as it like doesnt like respond correctlty
to the button press combinations only like the first sync+eject press is registered.

This type of symptom was also present before I asked for help on this forum.

 

To me the most suspect in the voltage on CE1/CE2. Its only like 1,8V depending which is selected. I looked up the memory specsheet and it says its a 3.3V part. Input High Voltage min 2V, Input Low Voltage max 0.8V.

So the 1.8V in grey zone so its not actually determined what will happen. I guess depends on the specimen what will happen.

So if I would tie one bank to 3.3V and second to 0V should I guess it would rule out the problem? Any hints on how to achieve it (what to connect where) ? Any other modification needed?

 

I double-checked wrote to them and re-read they are fine. Writing to one does not overwrite the other.

Question - does the ACE keep CE1/CE2 at certain voltage all the time or does it switch it based on some other events other than the sync button pressed? Can you perhaps elaborate on the logic used there?