My latest experiment is to see if I can control my Astro decoder via the serial port on the back, so I can have Freevo record from different channels (currently I'm mostly recording the kids shows from NHK that are on in the middle of the night, so we have to remember to leave the decoder on channel 963 each evening). There is of course no documentation about the serial port anywhere on the net, but a few US set top boxes have been hacked, so there is some hope.
What I know after an hour of poking around:
Model Number: DSR4201/68
Serial port: 115200 8N1 (diagnosed by observing the output)
Firmware seems to be developed in France, as the only thing I have got out of the decoder so far is some debug messages in French as I shut down. Thomson also supply decoders to Astro, so maybe they are providing the firmware for both their own and Philips boxes?
Here is the output I see:
TE : c0c9877c : Ln : b40 > ini_mem
TE : c0c9877c : Ln : b40 > : free_mem
TE : c0c9877c : Ln : b40 > gmhw_init
TE : c0c9877c : Ln : b40 > appel a la fonction Get_Dynamic_mem, retour 0
TE : c0c9877c : Ln : b40 > Valeur de la taille totale dispo pour Partition Privee =2363736
TE : c0c9877c : Ln : b40 > Adresse de la memoire Dynamique 0xc0dbeea8
TE : c0c9877c : Ln : b40 > ok
No hits on any of that on Google unfortunately, so I'm on my own.