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Table of Contents
Hacking the Zsun WiFi SD Card Reader
The goal of this project is to learn as much as possible about the Zsun WiFi card reader and run OpenWrt on it to turn it into an awesome wifi device.
People Involved
- emeryth (emeryth at hackerspace.pl)
- q3k (q3k at hackerspace.pl)
- informatic (informatic at hackerspace.pl)
State
All the important aspects of hardware are understood.
OpenWrt confirmed working, but no easy way of flashing yet.
Hardware
- AR9331 SoC
- 64MB RAM
- 16MB SPI Flash
- GL827L USB SD Card Reader
The device consists of two PCBs sandwiched together and connected via 8 pins.
The bottom PCB contains only the SD card reader chip and SD slot, it can be safely removed without affecting operation.
Serial Port
The serial console is brought out on testpoints (see pictures). Bitrate is 115200.
Ethernet Port
There are also testpoints for connecting an ethernet port.
Use a Magjack or similar connector with magnetics.
This port is required for uploading images to u-boot.
USB switch
The device contains a WAS7227Q USB switch, which connects the sd card reader chip to either the USB plug, or the AR9331 SoC.
The switch is controlled with GPIO21.
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!