This article will discuss the ROM read/write issue, which is very important for Western Digital HDD repair. As M25P10 chip is widely used as the ROM on WD hard drives, we will take M25P10 as an example:
When the M25P10 chip is in a good status, we can perform read/write process directly through PCBA (just set the jumper setting of the HDD and connect it to our console, you can read/write the ROM by using the functions built in the “ROM and HEAD Operations” tag). But since the controlling program of ROM read/write is stored in the ROM also, if the data stored in the ROM is corrupted/missed, the program controls the read/write towards the ROM chip would also be damaged or non-available, that’s why we can’t read/write the ROM through PCBA by using the main program. For this kind of condition, the ROM chip should be unsoldered from the PCBA and use programmer to perform read/write process on it. All the following description is based on the condition that the ROM data is corrupted. For WD hard drive repairing when the ROM data is corrupted, we need to unsolder the ROM chip from the drive’s PCBA and solder it to the external programmer board included in our software package for reading/writing, and then unsolder the ROM from the programmer board and solder it back to the drive’s PCBA. That is to say that we need to perform unsoldering and soldering for 4 times in total. In these processes, customers will have the ROM chip damaged very likely. For solution, some customers worked out a new “solution” for ROM read/write and provided to us for confirmation:
Here is the “solution” stomers: connect the ROM chip pins to the chip programmer using cables directly without unsoldering the chip from the PCBA, and try to read/write the ROM data using the chip programmer.