"HO-K SO!!! (in my "history of ze world" voice) turns out it is possible.... however its very involved and requires building open wrt firmware from sourse, porting old code from another device (exact same chipset tho), rerouting usb wires internally. *facepalm* the original porters from hackerspace already went pretty deep into this and my searching was unnecessary lol
GPIO
- GPIO0 - LED
- GPIO18 - card reader reset
- GPIO21 - USB switch
- GPIO22 - card detect
Hardware hacking
If you remove the card reader board you get easy access to one USB port and 3 GPIO pins.
Remember that GPIO is 2.5V!
GPIO pins and bootstrap
Here's a closeup of the bootstrap GPIO pins, perhaps useful if you want to try enabling USB device mode.
Bootstrap functions:
- GPIO 0 : Crystal frequency of external clock 0=25, 1=40 MHz
- GPIO 1 : Booting from internal 0=ROM, 1=SPI Flash
- GPIO 11: 0=General JTAG, 1=CPU ICE
- GPIO 12/28 : external memory type (00=SDR, 01=DDR, 10=DDR2)
- GPIO 13: USB mode 0=device, 1=host
- GPIO 16: Download firmware from 0=USB, 1=MDIO
USB device mode
AR9331 is capable of working as a usb device (gadget). Unfortunately the code for that exists only as a patch for an old version of OpenWrt:
http://neykov.name/posts/ar933x-usb-device-driver/
So if you want to use the zsun as a USB gadget you will need to:
- Port the code
- Remove the bootstrap resistor setting USB to host mode
- Remove the card reader PCB and rewire the the USB signal pins
and yes everything from winscp is on the internal memory i use mine with no card inside