October 12th, 2018, 16:16
October 13th, 2018, 9:17
October 13th, 2018, 14:07
Prove that f1 is driving 0 ohm.
d1 (tvs or diode zenes I do not know) does not have to be short-circuited.
With isolated pcb current.
f1 5v at both ends.
d1 on one end 5v on the other gnd.
Do you use MRTLAB or something similar, if you do not mind saying it?
October 13th, 2018, 18:39
October 14th, 2018, 10:23
October 15th, 2018, 14:41
Easy way to test IBM based PCBs including HGST, ARM BASED, ETC ....
- Plig the PCB only to your firmware tool or laking that plug it to the system and run something like Victoria, MHDD, HRT DEMO, etc on the port where you do have the PCB connected.
- Power it up and check register status.
- If the PCB goes to BSY for a while and then later it reports DRDY and DSC you should be able to try the Super On combination to access memory (arch M24) or normal Super On on ARM and read NVRam.
- If the PCB doesn't report BSY and then DRDY and DSC the PCB is NOT working as expected.
- If you don't have specific firmware tools and you don't know VSCs to use with HRT DEMO for example you can simply check register status and it should provide a clue ...
- Most IBM/HGST will have a FUSE that will blow up on the PCB and if that is the case there will be no power to the MCU, etc and you will not be able to gain ATA access. Most IBM/HGST will not have shorted TVS (like we see allot on WD PCBs)....
- IF TVS/diode is shorted your PSU will shut down. That is exactly the function of the TVS .... It prevents the power from entering the drive by shuting down the PSU due to the short. It will be like if you apply power to ground. A fuse will just stop the power from flowwing as there will be an open "cut" on the circuitry, it's like when you lift a switch ... Power will not be able to flow but PSU will not shut down as there will be NO short circuit. You can "bridge" the fuse and the power will flow again but on the TVS case you should REMOVE IT to remove the short and you need to bridge any fuse that is broken ... Of course that if the PCB does have further issues or the power supply is got stable you will fry the rest of the PCB ....
- As my experience goes when i do have damaged HGST/IBM PCBs that do not report BSY/DRDY/DSC and when i try to "fix" fuses on those they tent to ALLWAYS blow somewhere else so i don't bother anymore, i just replace the PCB.
- You need to move ROM chip (on ARM) + ROM chip and NVRam chip on older IBM based drives from the broken PCB to the new one, assuming the code on the chip is ok.
- If you have a drive with damaged NVRam you should still be able to see the DRDY and DSC and you should be able to use the VSCs to read/write NVRam.
No spin could also be caused by bad heads.
October 18th, 2018, 3:03
October 18th, 2018, 15:06
abolibibelot wrote:How can I say for sure if it's a problem with the PCB or with the HSA ?
October 28th, 2018, 19:47
November 5th, 2018, 20:54
What i was saying was if you use some tool that can show the register status of the drive like MHDD, Victoria, etc or if you have any comercial firmware tool like PC-3000, MRT, HRT, etc and if you plug PCB only on ANY IBM BASED drive (arch M24, ARM based, etc) you should see this IF THE PCB IS STILL WORKING :
On IBM/Hitachi/HGST (IBM NATIVE) drives with DAMAGED PCB on all cases that i did have so far there are NO ATA INTERFACE meaning normaly a fuse will blow or whatever and the PCB will NOT REPLY BY SATA/IDE meaning that with your firmware tool or MHDD, VICTORIA you will NOT SEE BSY and DRDY/DSC . You will only see exactly the same as if you were selecting a channel without drive ! There will be no register status as the PCB will be dead and it will be exactly like not plugging any drive at all. Depending on the system you might see all register status lit, error, abort, etc ..... it will display exactly as it would without any drive so no drdy and dsc.
- From here you can issue the "universal" "Super ON" to gain access to NVRam for M24 arch drives or the Super On for ARM drives and then read RAM or read NVRam or whatever. This does work with PCB ONLY as explained !!!! Example on M24 arch :
For the record i was NEVER able to repair a single IBM/HITACHI/HGST PCB so replacing with compatible PCB + moving ROM (OR ROM + NVRAM) should do the trick.
If PCB reports DRDY+DSC and if you can read NVRam most likely the "problem" is elsewhere .... Check NVRam and if it's OK and if ROM is ok as well most likely PRE-AMP (inside drive) is gone ...
November 5th, 2018, 22:20
Measure the voltages at the test points marked +5V, +5V fused, Va, Vb, and Vcore.
November 6th, 2018, 0:21
November 6th, 2018, 15:03
abolibibelot wrote:(...)Is there a way to dump the ROM with a free / demo software tool, then have an PCB seller copy it to the ROM chip of the replacement PCB ? If I'm not mistaken, it seems to be possible with WD drives and WDMarvel Demo, apparently there's no such luck for other brands, is that right(...)
March 4th, 2019, 20:32
March 5th, 2019, 22:01
March 7th, 2019, 12:04
You need to move ROM chip (on ARM) + ROM chip and NVRam chip on older IBM based drives from the broken PCB to the new one, assuming the code on the chip is ok.
March 7th, 2019, 19:22
March 9th, 2019, 21:29
(...)– Generally speaking, what would be the recommended course of action in such a situation, to solve the issue at a “reasonable” cost ?
April 13th, 2019, 16:15
Can you retake the voltage measurements, this time with the black probe on a ground point?
Send the drive to a reputable data recovery firm or browse for PCB re-sellers that do sell PCBs and offer free adaptation service / move NVRam to new PCB. This option will not work if the drive does have other problems to add to the "possible" PCB problem ...
April 13th, 2019, 18:47
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