Jasper 512mb - No video after Xell, NAND dumped/wrote fine

[wompa164]

Hi everybody,

Doing my first JTAG with a brand new 512mb Jasper. Before you ask, yes it's exploitable (found a stash of April 2009 Arcades at my local Best Buy) and I've managed to extract the NAND and dump the keyvault/config with no problem.

The problem (and I know a lot of people with 512mb Jaspers seem to be experiencing this) is that after flashing Xell, I can't seem to get any video upon boot. As soon as I flash back to my stock NAND, it boots up just fine. I've tried this a couple of times now, including resoldering the JTAG connections and still no go. I'm using the standard MS component AV cable (tried in both TV and HDTV mode) with no luck. I checked the diodes with my Fluke and when all the points are soldered, I get out of spec readings (basically, non 0L readings) when the polarity is reversed across the diodes, which I don't understand unless the diodes are bad (not really an electronics expert). After removing all of the wiring and diodes, they test fine again until I make the final connection to the front panel point.

In a nutshell:

- No problems reading/writing NAND (works after flashing back to stock, compared a dump of my NAND flashed with Xell to the actual 'jasper_6723_hack_for_256mb_512mb.bin' and everything matched up
- Using component cable, tried booting with the eject button and rear USB port
- Resoldered connections multiple times with no luck, only blinking green LED and no video
- Help?

[wang]

don't inject the config, i had the same problem with my jasper

[wompa164]

I'm not injecting the config, I'm straight up writing the 2mb (less actually) Xell bin.

Also, could anyone verify their MD5 checksum for 'jasper_6723_hack_for_256mb_512mb.bin'? My file is returning 'c82bff1c7349136739cded154725147e', just want to make sure I'm working with a known good copy.

[Arakon]

don't inject the config, i had the same problem with my jasper

Just cause you had issues with it doesn't mean the config should just be left out. It contains unique calibration data and the MAC, it should never be left out.

@wompa: get the file from xbins, that one is definitely good.

[wompa164]

Just grabbed the file from Xbins, MD5 matched up fine.

[maximilian0017]

Just grabbed the file from Xbins, MD5 matched up fine.

What kind of diodes did you use?, pics?
What light come on when you power the xbox up?

If you can successfully reflash back to normal the reading/writing should be ok(you did make a couple of dumps and compere them right?)

Oh and flashid and CB version would be nice

[sic]

- No problems reading/writing NAND (works after flashing back to stock, compared a dump of my NAND flashed with Xell to the actual 'jasper_6723_hack_for_256mb_512mb.bin' and everything matched up
- Using component cable, tried booting with the eject button and rear USB port
- Resoldered connections multiple times with no luck, only blinking green LED and no video
- Help?

I have exactly the same problem with my exploitable april ´09 jasper 512mb box, and as you wrote I have also seen/read that more ppl seems to have this issue with their jasper 512mb boxes.
Have been searching for a while now but haven´t found a solution that works. Some of the things I have tried is:
Different wires and lenghts
Different resistors at jumper point
Different diodes
Tested both sides of MB
Tried all alternative points
Formated internal MU
Flashed Xell, Xellous and XBR

I can add that I have jtagged other boxes (not jaspsers) without any problem at all.
   

[ZprivateZ]

I've flashed 3 512mb Jasper boards using xellous and never had a problem out of any of them and I have always injected the config into them also. Are you flashing xell or xellous? maybe that's your issue.

[sic]

I have tested xell, xellous, xbr but always the same result, a green center led and black screen.. Tested with and without config and kv..
And if I reflash original nand the box boots up without any problem..

[wompa164]

Got it!

I'm using the Maximus NANDFlasher and the installation kit (I know I know), and it turns out the JTAG module includes a 100Ohm resistor by default - you have to bridge a jumper on the quick solder board to bypass the resistor.

There was absolutely no mention of this in the product documentation and when I spoke with Ed at VGC Repairs the day I received the flasher, he mentioned that the jumper should only really be used for Falcon systems - apparently not! I was tearing my hair out for nearly 2 days straight trying to get my wiring working, but after rewiring literally everything (even tried alternate points for B1F1 and the front panel header) and having zero luck, I decided to bridge the jumper for $#!ts and giggles and my face lit up like a kid on Christmas morning when I saw that beautiful blue screen.

Thanks for the help everyone, hopefully this helps someone else out that has similar problems with Maximus' kit.

[xbox360noob]

well, that's what you get when you are too lazy to do some work on your own. don't want to be a smart ass here, but you would've saved yourself lots of trouble without this redundant product...