data-medics wrote:
fzabkar wrote:
Does anyone know why? Which CPs are mandatory and what do they do?
Because all the CPs except basically the G-List and S.M.A.R.T. are stored in the ROM chip. There's very little on the platters for a service area at all.
While it might be theoretically possible to rebuild the translator, p-list, etc. from scratch it's not practical in the real world. Maybe if deepest Russian secrets were stored on a drive it'd be worth the crazy amount of manual effort, but not for a typical case.
I understand where the CPs are
stored, I just don't understand what they
do. In fact some Toshiba models do have copies of some ROM based CPs in the SA, although you would need to reach the SA to make use of them. Catch 22.
If I were investigating this issue, I would "disturb" a particular CP and observe the sensitivity to these disturbances. That is, I would vary a particular CP parameter in both directions and determine the range over which the drive remains stable.