hclx / dell_power_spoofer Goto Github PK

Hi! Seen your blog, nice work. I can't really do that hardware mod, but i have an idea: manually entering the required values to laptop's embedded controller. Tested out with RW-Everything, when i plug in a broken adapter, and it's charging for 2-3 seconds, then disables, the following happens:

• Byte 0x07 changes to 20 while charging, then E0 when it disables
• Byte 0x3B changes to 30, then 31

Tried to enter these values, but instantly reverts back to disabled. Editing byte 0x06 sometimes brings up the QuickSet app's unknown adapter warning, for example at values 01, 03, 09, etc.

Also there is an empty space, maybe the laptop would store here the data received from charger?

Found your code...

"Memory dump:

String format: DELL00AC090195046CN09T2157161543835EAL03

Hex format:

44 45 4C 4C 30 30 41 43 30 39 30 31 39 35 30 34 36 43 4E 30 39 54 32 31 35 37 31 36 31 35 34 33 38 33 35 45 41 4C 30 33 E0 A9 FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF
FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF"

Maybe entering this to empty space should force the laptop to charge, but i don't know, where to start it in bytes? Thanks for reply! :)

Great work! Thanks for sharing.

There are two hardware suggestions I have which aren't too important for a hobby project but are good practice. They cover unlikely scenarios, but are worthwhile for robustness.

First, I suggest adding a reverse diode across the regulator, with the anode at the regulator output. If the input voltage drops below the output voltage, which can sometimes happen during power off, the pass transistor in the regulator can become damaged by reverse current. This is probably unlikely since the power supply output likely has a very long holdup, but it won't hurt and there could be conditions that would cause the regulator input voltage to fall first. A standard 4148 will suffice.

Second, depending on what receives the signal in the laptop, it may also be prudent to put Schottky diodes from ground to the uC signal output and from the uC output to +3.3V. A series resistor between the uC and diodes is also good protection. The receiving circuitry could pull the pin below ground or above +3.3V in an unexpected condition, generally a serious fault, which would likely damage the uC.