ST3750528AS

[ShaneWard]

Hi all,

Got a few of these of ebay as faulty drives and hooked them up to terminal to see what was happening and they seem to be fine. I get the

Rst 0x20M
Servo Processor Is Reset.
RW: Disc Ctlr Initialization Completed.

ExecuteSpinRequest

(P) SATA Reset

But when I try to enter terminal through the ctrl + Z command, nothing happens. Its like terminal is locked or frozen. I saw a post about shorting the read channels, but is that what I need to do to get terminal to work.

I'm planning on selling the PCB boards anyway, so they look to be working, drives spin up and read, but looks like a ton of bad sectors in important areas of the disk to stop formatting, creating partitions and so on.

Many thanks
Shane

[ShaneWard]

Here are some images of the PCB. Which channels do I short to get terminal responding. Not sure if the read channels should be shorted to ground.

[ShaneWard]

I'm looking at the forums, wondering if this might need 1.8V to work, or its a low voltage board. Not sure if it is. I get the terminal information, but cannot Ctrl+Z into terminal. Its only locked on (P) SATA Reset. Any ideas?

My USB Serial adapter uses 3.3v I think.

[fzabkar]

Tip: How to identify the Read Channel test points:
http://www.hddoracle.com/viewtopic.php?f=24&t=123

[ShaneWard]

Thanks for that. I haven't done anything with the drive, it more like a hobby fix if I can, but one question still remains, is this terminal voltage on this PCB 1.8V OR 3.3V

I think it's 3.3V because I am able to see the drives output terminal results, but I cannot enter the terminal mode or send commands.

Also, do these drive run a self scan when sitting Idle. Hopefully that might map bad sectors in the system area if I leave it running.

Thanks for help
Shane

[ShaneWard]

This drive has be baffled. I shorted the read channels every way possible, together, to ground and so on but nothing seems to get the drive into terminal. I even put a bit of paper onto the Head stack connector and that did not work, only got the ready status flags on the terminal screen.

I tried it with the pcb off the drive, and it only does the same result.

I only managed to get the drive into terminal for a second when I constantly held the Ctrl + Z key while it booted up, then it would just go to P sata reset and then nothing.

So, Not sure what is going on. Anyone experience this behavior and got it into terminal?

Its a F3 arch drive too. Also from the label is looks like its a repaired drive from Seagate with firmware CC46. if thats helpful.

As before, its an empty drive I am messing around with.

[ShaneWard]

This drive is getting annoying, I feel a terminal format through the system area will solve it completely, but I can't get the damn terminal to start. Or when it does start, its for half a second before it freezes. I tried all the ways, shorted this, shorted that, took board of drive, and the only way I got terminal to come up in the first place was shear luck or if my fingers were all over the PCB when I booted it up. Nothing...

Any ideas??? I feel its something to do with the Firmware on the chip?

[MindMergepk]

are you shorting the correct read channels ... i think of these points as read channels

Attachments

[ShaneWard]

Yes. I've done that. The drive starts to seek and try and find the data. When I un-short it, it recalibrate and works as normal. But Terminal not accessible.

[ShaneWard]

Anyone got any great ideas on how to get ternimal started on this drive?

[MindMergepk]

maybe timing of shorting read channel is not correct.
try shorting at different times.. you should get access to terminal

[ShaneWard]

Still no luck in trying to get terminal to work on this. I tried all the timings as well. its like its been locked or something. Or the TTL adapter might not be computable.

This is the USB to TTL adapter I am using: - https://www.ebay.co.uk/itm/USB-To-RS232 ... 2749.l2649

I receive all the messages okay, but no command seems to work.

Shane

[unknown]

Try the terminal adapter with another working drive to be sure.
Bad terminal always lead to misdiagnosis.

[ShaneWard]

Thanks, the adapter works with other drives I have just fine. I was wondering if this drive responds to a lower voltage compared to the 3.3v one.

Shane