Airlink101 AR725W
Supported Versions
Hardware Highlights
Installation
Flashing
The factory firmware expects a header, apparently proprietary to routers based on Gemtek boards.
/* Gemtek */
typedef struct {
unsigned char magic[4]; /* ASCII: GMTK */
unsigned char version[4]; /* x.x.x.x */
unsigned int pid; /* Product ID */
unsigned int imagesz; /* The length of this image file ( kernel +
* romfs + this header) */
unsigned int checksum; /* CRC32 */
unsigned int fastcksum; /* Partial CRC32 on (First(256),
* medium(256), last(512)) */
unsigned char build[4];
unsigned char language[4];
} gt_imghdr_t;
The program mkheader_gemtek, part of firmware-utils, generates this header from a uImage. The header is not written to flash.
Default layout
The bootloader is uBoot.
Mapped starting at 0xbc400000:
0x000000 - 0x050000 uBoot
0x30000 uBoot environment variables
0x40000 RT2872 EEPROM data
0x40004 MAC address
0x050000 - 0x130000 Linux Kernel
0x130000 - 0x390000 RootFS
0x390000 - 0x3e0000 LANGUAGE_PACK
0x3e0000 - 0x3f0000 NVRAM
0x3f0000 - 0x400000 NVRAM_FACTORY
Since the language and NVRAM partitions are only used by the factory firmware, OpenWrt uses a single partition starting at 0x50000 and running to the end of the 4MB.
Hardware
Networking
The SoC's builtin Ethernet is connected to a IP175E 5-port 100mbit switch. VLAN setup is supported in OpenWrt.
Serial Port
The serial port is located at J6 on the board. The baud rate is 57600.
TXD 0 0 VCC 3.3V
0 0 VCC 3.3V
0 0 GND
RXD 0 0 GND
0