Tivo Series 1 Startup Sequence

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

Did you get anywhere? Doesn't WinMFS have some boot repair or restore function