Seagate's new family of products in recent years increasingly restricts access to ROM data in Bootcode mode. Additionally, there is a binding relationship between their circuit boards and ROM data.

For example, drive a supports reading and writing ROM, while drives b and c do not support reading and writing ROM:

a.AF-ST1000LM035-1RK172-EB01-ZDEG5YPR    100835923 REV A YES

b.AF-ST1000LM035-1RK172-EB01-WKPRCYNC   100835923 REV A NO

c.AF-ST1000LM037-1RC172-SED1-WQ9CEWD8  100835923 REV B NO

REV A has two types: ROM writable and ROM non-writable. It is currently known that all REV B types are non-writable. To differentiate it from firmware lock, we can refer to the feature that prohibits reading and writing ROM as ROM download lock, which changes the ROM structure and algorithm.

When we replace the PCB with a ROM non-writable PCB with a ROM writable PCB, we find that the hard drive does not work properly. In summary, there is a binding relationship between ROM data and PCB, and it is not allowed to replace it with other types of REV A or REV B circuit boards at will.

In other words, to ensure the normal operation of the hard drive, it is necessary to use the original PCB. Currently, the most common method to operate the ROM is through chip-level soldering, and we have released related tutorials:

http://us.mrtlab.com/tech/seagate/350.html

Since the chip-level soldering method is relatively complex, Seagate's ROM read and write operations are quite common. When developing the Western Digital SATA balancer, we also considered the solution of Seagate's probe board, which maintains the same ROM read and write operations as the SATA balancer. The following is a video demonstration.

Bilibili：

YouTube：