reply to random
Re: Upgrading Firmware on Thompson DCM475 There is a parallel port to SPI FLASH programmer that only require 4 resistors and a power source. I guess you have to magically obtain a copy of the firmware which tends to be the hard part.
rayer.g6.cz/programm/programe.htm look under SPIPGM.ZIP
>SPIPGM.ZIP ver. 2.1 [98 kB] (DOS/Win9x/NT/2k/XP/Vista/7/Linux) is a tool for programming serial SPI FlashROM memories attached to PC via parallel port cable. It can identify device, read, write, verify, erase and unlock flash memory. More info about needed hardware (CZ-only but schematics is self-explaining) here.