(UEFI) Dell XPS 15z L511z modded BIOS - and HOWTO

[TimeWalker]

Most importantly @kasar remove power from the laptop completely (AC/battery block/3.3 coin-cell battery using your switch) when attempting any magic on the chip.

oh, you know that apparently
for 3.3V use a coin cell battery (same one you have in the laptop) because if using a pulse-type source you would need to use capacitors on the circuit.

[kasar]

yeah, I will, that was another reason about why I made the cmos settings switch

the mobo must be lack of any power execpt the one from the programer while attempting to backup or write things

[TimeWalker]

And make sure your cables are as short as possible, this flasher software is finicky .. i've seen people had to reduce the length of the cables to about 10cm to get a proper dump/flash.

[jkbuha]

Guys just saw this now. Good luck kasar (remember your ESD straps )
Rep to both - even if it won't ultimately work. Stuff like this takes cohones....

[kasar]

oh sh1t!

I think the wires from the chip to the internal plug I added are already like 20 cm

well, I supose a way to be sure the stuff is working fine, would be to take 2 /3 backups before flash anything and hex compare them, if everything is good the dumps should be identical I guess

edit: thx jkbuha

ESD straps? ¿ what u mean?

@all is just me or the forums are deadly slow again? D:

[jkbuha]

ESD = Electrostatic discharge straps - to prevent static buildup and fry your mobo
But from the sound of things you're working in a humid environment, so no static

[TimeWalker]

ESD strap is an anti-static wrist strap. I have one around because I never actually believed you can kill electronics with static until I actually managed to do this .. completely by accident. A 200$ graphics card ...
Yeah, the redundant dump approach should be a proper way of troubleshooting.

Yeah the forums seem kind of slow .. I guess Wiz is implementing another server and redirecting traffic.

[kasar]

ah, ok yeah, I allways touch the chasis of one of my old desktop machines while I am going to do electronics stuff ^^

I also doenst wear shoes while I am at home

I think that also helps to keep myself discharged

[kasar]

ok, almost completed the cable.

but I need help to connect the four last wires


in one side I have



and the another side I have




in my port side, aparently.

3.3v line goes to VCC, WP, and HOLD.

and GND goes to GND obiusly

but I'm not sure how to connect the 4 important wires

on my port side I have

- DI (IO 0)
- CLK
- DO (IO 1)
- /CS

and at the programer cable in construction I have

/CE
/SCK
/SO
/SI



aparently in the schematic, it ask about the chip legs, so I think the correct join match would be something like this:


- DI (IO 0) --> /SI
- CLK --> /SCK
- DO (IO 1) --> /SO
- /CS --> /CE

is this correct?


programer cable process:

[TimeWalker]

- DI (IO 0) (Data Input) = SI (Serial Data Input)
- CLK (Serial Clock Input) = SCK
- DO (IO 1) (Data Output) = SO (Serial Data Output)
- /CS (Chip Select Input) = CE (Chip Enable)

Yes, correct @kasar

---

Zener diode in reverse bias is not really a good way of dropping the voltage down to 3.3 .. and the cable is waaay to long.
I would opt for a low-drop v-reg of some sort .. a TS1117CW-3.3 or a LD1117DT33 for example.. with a pair of 10uF tantalum caps to support it.