External rom reading (through programmer , Is it reliable

[terminator2]

Recently I have got 2 cases of seagate Desktop hard disks , in first case someone has burnt eprom ( was physically damaged may be while trying to remove)
in other instance it was altogether missing.
I would like to know whether it is good idea to read eprom without removing ( using external programmer ).
Those electronics experts might be able to give there opinion. It is most safe method as it does not involve application of heat or manual efforts.
can someone shade light on this. Also I would like to know which programmer will be suitable for this.
Here I am concerned with Desktop hard disks first .
Thank You.

[pepe]

it is usually possible to read flash chips without removing them from the pcb. I use my own built reader which has programmable vcc and it works most of the cases.
However i can't recommend a commercially available one, coz i do not use any of them. I have an EETools TopMax which was pretty nice at its time but it is limited with new devices. It was able to read chips when the vcc was set somewhat lower than the circuit's own nominal vcc, because the cpu was held in reset in that case.
It is also possible to read those flash chips through a serial port most of the times.

pepe

[fzabkar]

I've been told that you can short the crystal to keep the MCU quiet.

[terminator2]

Thanks a lot pepe for sharing vital information.
So it can be done and may be is safe method. Unfortunately I am not expert in manual chip reading so will have to rely on commercial direct chip reader solutions.
any other device one can recommend ?

[terminator2]

In some earlier posts " POMONA clips" are recommended .Now can someone pls. suggest some programmer model which supports clip attachment ?
I am looking for entry /mid level device so as to suite my budget.
Also I would like to know whether "SOIC Clip, 8 Pin" will be enough to read old /new desktop laptop hard disk roms.
Thank you , have a nice weekend.

[posidon]

I feel this is risky process though I have not used these clips myself.
fzabkar and spildit who experiment with electroics may be able to guide.
In case if accidentally shorted will rom get damaged ? Also what if clip is connected in opposite direction. Is there any difference in resoldering rom directly or reading /writting through reader / third party software ( for accuracy of rom data)
I think most of our hard disk roms work on 3V (pls. correct me if wrong)

[pepe]

Also what if clip is connected in opposite direction.

the answer is current limit. And of course, be careful not to connect it reverse.

I think most of our hard disk roms work on 3V (pls. correct me if wrong)

most of the hdds produced in the past 5 years use 1.8V and 2.5V and none use 3.3V flash chips.

I've been told that you can short the crystal to keep the MCU quiet.

yeah, that's a good idea. I was thinking about pulling the reset line active but it is hard to find, takes considerable amount of time. Shorting the crystal sounds a lot better.
pepe

[digisupport]

Have been using a REVELPROG IS since january last year, before that I used a Barlino ll from Batronix.
On almost all drives I have seen the last year, ROM was read while on PCB. Various test clips and a small homemade jig works great for me.

[terminator2]

Thank you digisupport and pepe
Both REVELPROG & Barlino ll are top notch.
Thanks a lot pepe for cautions , I will be extra careful not to make reverse connections.

[posidon]

I am getting problem in buying REVELPROG-IS /Baltronix in India. Either they are not readily available nor they are affordable (for only eprom reading )
other option is elnec but it is also not available.
All I could get is TL866 and other generic chinese variants. Can someone from India suggest any other professional brand which is available in India.

[pepe]

Hello,

if you have more time than money to spend on commercial ones you can build your own as i did. My concern was to keep myself independent of sw updates and being able to add whatever device i need.
I found this for you (but there are other interesting projects as well):
https://learn.adafruit.com/programming- ... t/overview

i guess you can modify the sw for your purposes. I also used a digital potentiometer and an adjustable regulator to create programmable vccio for the target device and for the FT device.
pepe

[HaQue]

I've used products from https://www.embeddedcomputers.net/ with SPI chips with success

[terminator2]

I've used products from https://www.embeddedcomputers.net/ with SPI chips with success

Thanks HaQue.