Dynamic mask-ROM register patching

A method of starting a data storage device when power is applied to the data storage device, the method comprising:

• loading a reserve sector map into a memory of the data storage device from a storage medium in the data storage device;
• loading system sectors into the memory of the data storage device from the storage medium in the data storage device;
• and
• patching a Power-On-Reset (POR) register using one or more tuned values stored in a list in one or more system sectors, the list comprising an address of the POR register to be patched and the tuned value.

A data storage device comprising:

• a storage medium;
• a microprocessor;
• and
• a memory, the memory having stored therein a start-up routine that, when executed by the microprocessor, loads a reserve sector map into the memory from the storage medium, loads system sectors into the memory from the storage medium, and patches a Power-On-Reset (POR) register using one or more tuned values stored in a list in one or more system sectors, the list comprising an address of the POR register to be patched and the tuned value.