This is a case study of a Western Digital hard drive data recovery. The hard drive, model WD10EAVS, suffered from a burnt PCB (number 771537) and was not able to power up. The recovery process involved the following steps:

1. A donor hard drive was obtained and its firmware and ROM were backed up.
2. The donor PCB was installed on the patient hard drive and the donor ATA modules were loaded. The original firmware modules were then read successfully.
3. Module 01 was loaded to access the module list, followed by loading the module directory to RAM.
4. The donor modules were written to the patient hard drive and the firmware was restarted.
5. The original key firmware modules (03, 31, 32, 36, 40, 49, 4A) were written and the firmware restarted.
6. This allowed the data area to be accessed normally.

It is important to note that the donor firmware must be from the same family and have similar microcode.