26-08-2011, 07:49 PM
I spent quite a bit of time on the Toshiba PCX2500. I was able to read and write to it through a simple buffered jtag adapter. Once I accidentally erased the firmware and disabled it for a time. I was able to recover from my error by reloading the old firmware from a backup I made. In order to read and write to it, I used HairyDairyMaid utility for routers. Specifically I used
I would certainly enjoy getting into detail about the 2500, but my abilities to manipulate f/w is limited. I'm thinking it maybe as simple as changing a few bytes to get the modem to respond from a console. Then perhaps use the modem with a different MAC address?
Quote:HairyDairyMaid_WRT54G_Debrick_Utility_v48~cshore2.zip. I had to edit some things in the source to get the 2500 detected. There was also some fiddling involved in the way the bytes were ordered to be able to write back to the modem. I would have to revisit all my efforts to figure out how I did this. You can monitor what is going on while the modem boots via a serial console. The connections available on the circuit board. I got as far as being able to decompress (not accurately) the firmware image to it's fill size. The compression routine is credited in F/W to Mark Adler who created zlib library and gzip. I fooled around with several de-compress routines, but never got consistent results. There's another modem out there that uses the Toshiba TNETC4401 chip and I think it's a D-Link DCM-202. There is a bit of information on this modem, but not much on ppl tinkering with it.
I would certainly enjoy getting into detail about the 2500, but my abilities to manipulate f/w is limited. I'm thinking it maybe as simple as changing a few bytes to get the modem to respond from a console. Then perhaps use the modem with a different MAC address?