Here's some details to add a Mini-USB to your PSP Go cradle. Check the pictures for more details.
Mini-USB pinout:
1- +5V
2- D-
3- D+
(4)5- GND
PSP Go Pinout (related to USB):
1: GND (Ground can be found anywhere on the board)
2: D+
3: D-
4: GND (Ground can be found anywhere on the board)
8: +5V USB
You can solder the shield and the ground directly on the board from the mini-usb, between the power jack and the PSP go connector.
You will need to remove some plastic on the top part for the box to close.
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You can add a 3.5mm connector (audio) to plug your headphones or external speakers. You will need a connector that provide GND on a pin when something is plugged in. Or you can Connect the "Ena. Audio" pin to Ground but that way no sound will ever come out of your PSP when it's on the cradle.
PSP Go Pinout (related to Audio):
19: Enable Audio Out (when Grounded)
20: GND (Ground can be found anywhere on the board)
21: Right
22: GND (Ground can be found anywhere on the board)
24: Left
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Here's the rest of my findings (thanks to Sisee for the component part). But i'm not able to switch my PSP to Video Out, if someone can help me ^^
1: GND
2: D+
3: D-
4: GND
5: ???
6: ???
7: +5V (Not from USB)
8: +5V USB
9: ???
10: Component Blue
11: ???
12: GND
13: Component Green
14: ???
15: Enable Component Video Out
(Resistance 50k to GND)
16: Component Red
17: GND
18: GND
19: Enable Audio Out (when Grounded)
20: GND
21: Right
22: GND
23: ???
24: Left
25: ???
26: ???
27: ???
28: GND
Have fun