Sometimes there will be the need to replace the PCB of a Samsung drive, and sometimes it might be as well impossible to dump the contents of the original ROM.
While on the majority of the cases it should still be possible to attempt to acquire a PCB with the same firmware version at ROM level as the native PCB, in some occasions this might be very complicated and not very feasible as well.
Take this thread as an extreme example :http://forum.hddguru.com/viewtopic.php?f=1&t=30269
Here I'm going to demonstrate how to adapt a drive to receive a donor PCB if the original PCB is lost and if no BURN-IN resources are available.
1 - Acquire a donor drive that is fully compatible with the drive that you are attempting to repair. If you are trying to repair a drive with a USB only PCB then you will need a drive with an equivalent/compatible SATA port that is as well compatible for Hot-Swap.
2 - Plug the donor drive to your firmware tool. On this example I'm going to use SRT but you can use whatever firmware tool you have as long as it's compatible with your drive (SRT will only read/write firmware on relatively older drives and will have severe issues dealing with newer ones, but on this example it will work just fine).
3 - Read and save all of the modules of the donor drive. You can also dump and save the ROM as a preventive measure (If you are using SRT go to Service - Modules Operations and do a I/O - Read All).
4 - Issue the "Sleep" command. You can use Victoria for this if your tool doesn't support that function. Very carefully remove the screws of your donor drive PCB and place the PCB on the drive you are attempting to recover without removing the power to it neither removing the interface SATA/IDE cable to your tool. This way you can keep an eye on the status register. The procedure of Hot Swapping is explained in more detail here :viewtopic.php?f=117&t=714
5 - As soon as the PCB is in place and screwed back to the drive you want to recover (BE VERY CAREFUL WHEN PUTTING THE SCREWS ON THE DRIVE AND DO NOT SHORT ANYTHING
) you will need to issue the recalibration command (you can do this with your Victoria software by pressing "Recall").
6 - Open your firmware tool and go to Modules Operations. You can now READ all the modules on the patient drive and save them as backup. MAKE SURE that you change the working folder name if you are using SRT, otherwise the new copy will overwrite the copy of the modules you have done for the donor. Ideally you will rename the folder to something like "donor backup" as soon as you dump the firmware modules on the donor and you will rename the folder to "patient backup" as soon as you backup all the modules that you can from the drive you are attempting to recover.
7 - Now you just search for the OVERLAY
module (on classic Samsung) or for the MOVLY001
module (in Trinity Samsung drives) and you replace the module of the drive you are tying to recover with the copy from the donor. The idea is to have the same Overlay from the drive you picked the PCB from so that the code on your new PCB ROM will match the code on the MC OVERLAY (If you are using SRT be careful because the module that will be written is the one on the work folder. You will have to copy the module from the donor to the folder that you are using so it will be written to the drive).
8 - Now power off the drive, re-check the screws and plug the drive to the system. If all went as expected and if the PCB is compatible with the drive you will be able to use the drive as if the PCB was native from it. Just scan the drive with Victoria/MHDD to make sure all sectors can be read and/or extract the data if you are doing a data recovery job.
Hope this information is useful.