What is the problem with my NAND?

Everytime i try to downgrade my Jasper below 7776.1, it always errors out. I've seen someone with an 1888 Jasper XDK. I have no clue why my Jasper Test Kit fails to downgrade below 7776.1, even though i KNOW it is possible

 

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Nah, i don't think so. I took a dump from 20353, AFTER i upgraded to 21256.18 and no fuselines changed.

 

What i mean is that i downgraded to 20353 after upgrading to a 21256 recovery.

 

Checked fuseline 2 and it reads as no fuses are burned on fuseline 02

 

lol XD. but seriously, i've tried downgrading from 7776.1 and 21173.1. No success

 

Do you have anything between 7776 and 1888? Maybe it's too drastic of a drop....

 

Yes. But when i try to go down to 7645.1, I get 0x0000000c. And my recoveries originate from the 12-24-14 leak

 

Could be that you have a unit with big block flash - they will refuse to downgrade to a system version that doesn't have support for it. Attempting to bypass the checks results in the update apparently completing OK, but the unit then being unable to boot.

 

OHHHHHHHHH FINALLLY I FOUND IT OUT. Yes, unfortunately i do have a big block.

 

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256 and 512 = Big Block
anything else is small block

 

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Someone downgraded an XNA Jasper to 1888

 

Maybe they built a custom image - the guy I was talking to was pretty emphatic about old recoveries not working on big block flash units, and I tend to believe him since he was working for MS.

 

How? XNA's are BB.
XNA's are all Jaspers, so saying "XNA Jasper" is kinda redundant.

 

There have been reports of Falcon XNA kits, most likely very early expo kits.

 

Nope all are Jaspers fam

 

There were some Falcon boards which were found in the wild. It seems odd I know, but I've heard the same several times over and seen pics somewhere. Albeit I've never seen one in person as all of mine have always been BB Jaspers.