I have been trying to recover a drive containing a large number of recorded shows. The problem is very early in the boot sequence.
I have tried looking for a definitive guide for the boot sequence for a TiVo but am finding what appears to be disjointed info.

I have found a boot sequence for Linux that shows :
1- BIOS - Presumably in flash memory on the Motherboard
2- MBR - on HDD (hda4?)
3-GRUB - ?
4-Kernel - sbin/init
5-INIT -
6-Runlevel - etc/rc.d

How much of the above relates to a S1 TiVo.

My intention is to find a way of testing / fixing each step with the hope that I can recover the drive. I have copied the drive using dd with the intention of fixing the copy to avoid making the orginal drive worse. I have already proved that the problem resides in the drive not theTiVo motherboard.

Any ideas?
Thanks in advance