en el foro de AdslSpain y de mano "elguaton" q puso un post respondiendo hace algun tiempo sobre como hacerlo:
No necesariamente, cuando tu actualizas el firmware en modo consola no es necesario saber el password, pero cuando lo actualizas borras las configuraciones existentes y tambien dejas el password por defecto "1234",
Asi que para volver a conectarte al internet es necesario que sepas como a estado configurado tu router.
Te adjunto el procedimiento para actualizar el router en modo consola, que lo he encontrado en la web de zyxel:
In some situations, you may need to upload the ROMFILE, such as losing the
system password, or the need of resetting SMT to factory default.
The procedure for uploading ROMFILE via the console port is as follows.
- 1. Connect the console cable from the router to the serial port of your PC.
- 2. Start a terminal emulation program such as Windows HyperTerminal.
- 3. Configure HyperTerminal with 9600bps, 8N1, and the correct COM port that the router is attached to the PC.
- 4. Power on the router, you should see the router bootup message on the screen of HyperTerminal
- 5. Enter Debug mode during powering up the router when you see a message like 'Enter debug mode in 3 seconds.....'
- 6. Enter `ATUR3` to start the uploading
- 7. Use X-modem protocol to transfer ROMFILE. When select Sending File menu in HyperTerminal, you can choose X-Modem in the popup dialog box
- 8. After the upload has finished, enter `ATGO` to restart the router