I need clarification...
This means you don't even need the 12v converter because the AGS-001 arleady has the 13V power source on the motherboard by itself? That would be awesome!
Also when you are referring to "pin 28", "pin 34", etc you mean the pins of the place where the ribbon cable of the display goes in, yes?
So:
1. pin 28 -> P2VDD on board (for 13V light power source?)
2. pin 33 -> BT- on board (=ground) + a resistor in between?
3. cut off pin 34
Is that right? At least for the mainboard that you got?
EDIT: This is (mostly) all wrong
Sorry for the late answer, been gone for too long.
I am glad that you succesfully made it work!
This setup worked, because this screen was a drop in for AGS101 based on a IPS panel. This lets the screen work with less power, hence it came with a ribbon adaptor for a no solder instalation on 32-pin GBA001 (tested by me).
So, if it works in AGB001, it pretty much has to work on AGS001. The thing is AGS001 DOES has 34 pins too, but with differrent voltage from AGS101, so cut a trace, lift a pin and solder wires and resistor was mandatory.
As you have noted, my mod makes "believe" the fake screen that it was intalled on 32-pin AGB001 so it worked just fine. The resistor between pin 33 and ground is there because in AGS001, the button works as a on/off switch instead of a dimmer like in AGS101. By putting that component there, you don´t open the circuit, just route via the resistor (mimicking to some excent AGS101 behaviour)
So, AGS001:
Board AGS-CPU-11
pin 34 -> 5v (it has 1 led for frontlight originally)
pin 33 -> Switch backlight (its a circuitry, buts acts like a switch)
pin 32 -> GND
pin 28 -> P2VDD (in schems, stated as a 13v source for contolling contrast, confirmed by the bridge in the ribbon adaptor that came along)
So, you lift (or cut its trace, depends on board type) pin 34 connector from board and bridge it to pin 28 (or some TP connected to it) to feed 13 v to the FAKE screen (not tested on original, I assume it will not work). Next, bridge pin 33 connector to GND though a resistor, so the voltage drops near the output originally intended from it and acts as a dimmer. DONE, ready to enjoy.
It will not be VERY bright, but that comes with few advantages:
* no need to source extra parts (step-up, doble sided tape, etc)
* battery life is extended compared to the step-up install
The step up is only needed if you are installing a original AGS101, as of others says, that thing will not backlight wit only pin 28 power (Can't confirm as I do not own one to test).
I have tested the sleep function in Super Mario 3 and it worked fine, the screen and sound goes off when you press L+R+SELECT
Hope this solved your doubts.