Here a list of Access Points that have a JTAG interface (IEEE1149) on their board, and that are potentially hackable to run linux.
Dlink_DI-614+revB2, Conexant ARM9
Dlink_DWL900AP+, Conexant ARM9
MinitarAP, Realtek RTL8181, SOC
To port linux on those boards, we need:
- pinout of the JTAG ARM9 connector
- BSDL description of the CPU
- digging into the sources of the linux distrib that comes with the Hactiontek router
Problems
some of those routers include Linux and other Free Software without giving any source code: GPLViolation


