25 Series eeprom voltage

[terminator2]

I have brought Revealprog IS eprom programmer and its my first chip reading through clips.
I have connected a seagate PCB for trial. , Programmer reads ID and identifies manufacturer (winbond) butit saves eprom in 128KB file only.
Wherein in PC3000 it reads 1MB eprom.
do I will have to select volatges manually ? Default voltage here for 25 series is 2.8V.
What could be wrong.

Attachments

[terminator2]

I thought I might not be needed to set VPP voltage manually and if series /model selected eprom programmer will automatically select appropriate voltage. But that does not seems to be the case.
I am getting errors of over voltage protection /high current etc.
Curently I am only studying this device so no actual client disks are involved.

Attachments

unnamed.png (4.35 KiB) Viewed 20279 times

[digisupport]

I use Revelprog with clips. But i always select the right chip manually before reading any thing.
Never let me down, not a singe time.

[fzabkar]

The "overload" error is due to the fact that your programmer is powering everything which is connected to the same supply as the EEPROM. Apparently its current limit is 100mA.

The appropriate voltage for in-circuit reading/programming is the voltage that the circuit was designed for. Measure it and then set your Revelprog's voltage accordingly. Flash memories have a wide voltage range, so your programmer may default to a supply voltage which is nearer to the top of the range. This may have bad results if the other chips on the PCB cannot tolerate it.

Secondly, 128KB = 1Mb, ie Bytes versus bits.

[terminator2]

I use Revelprog with clips. But i always select the right chip manually before reading any thing.
Never let me down, not a singe time.

Thanks digisupport.
I think I have done some mistakes in connecting POMONA clips to Revealprog IS.
I have connected cables from FRC cable ( total 8 out of 10 ) to clip sequentially. Like shown in above Image , is it right connection ?
Also which model I should choose , sending you more details in PM.
Thank you.

[terminator2]

The "overload" error is due to the fact that your programmer is powering everything which is connected to the same supply as the EEPROM. Apparently its current limit is 100mA.

The appropriate voltage for in-circuit reading/programming is the voltage that the circuit was designed for. Measure it and then set your Revelprog's voltage accordingly. Flash memories have a wide voltage range, so your programmer may default to a supply voltage which is nearer to the top of the range. This may have bad results if the other chips on the PCB cannot tolerate it.

Secondly, 128KB = 1Mb, ie Bytes versus bits.

Thanks fzabkar
I thought its automatic and easy process to read chips through clips. Can You pls.tell me what voltage I will have to select for reading hard disk pcb roms.
Are there different types for which different volatges need to select or for entire 25XX series single voltage is applicable.
There is risk of rom getting damaged due to imappropriate voltage.
When I read rom through PC3000 it comes out to be of proper 1MB then why 128KB here ? I tried to read this chip but it is garbage and not recognized by pc3000. I am making some big mistake here. What is VPP for all eproms generally we encounter on hard disks pcb ?

[fzabkar]

Power up the PCB (without connecting your Revelprog) and measure the voltage between Vcc (pin #8) and Ground (pin #4). That's your supply voltage. It will be 1.8V, or 2.5V or 3.3V. Now power off your PCB and connect the Revelprog.

What don't you understand about 1Mbits and 128KBytes? Can't you see that they are the same thing?

[HaQue]

128 KB = 128 Kilo Bytes
Kilo means 1,000

128,000 Bytes = 1,024,000 bits
1 MB = 1,024,000 bits


1 megabit = 1000000bits = 1000 kilobits.

[pepe]

Sometimes you get better result by setting VCC a few tenth of a volt bellow the nominal VCC for the board, this avoids starting up the MCU and interfering with your reader. As Franc said, the serial flash chips are operating in a pretty wide Vcc range, so that somewhat less voltage won't affect reading. For first tests i would start with chips desoldered from the pcb. And of course, test on some spare pcbs, not patient ones.

pepe

[fzabkar]

128 KB = 128 Kilo Bytes
Kilo means 1,000

128,000 Bytes = 1,024,000 bits
1 MB = 1,024,000 bits


1 megabit = 1000000bits = 1000 kilobits.

When talking about memory chips, 128KB = 128 x 1024 bits, not 128 x 1000.

1MB = 8Mb = 1024 x 1024 bytes = 1048576 bytes = 1048576 x 8 bits = 8388608 bits

[HaQue]

yes. When I posted I was thinking this isn't right, but was at work and got sidetracked. I was more trying to point out that they were the same with an example, but yes, my example was dodgy. Thanks Franc!

[terminator2]

Thanks to all fzabkar , pepe ,HaQue and digisupport.

Now I have realized that chip reading even through advanced programmer like Revealprog is not completely automated process and manual input is needed.
So I check no of one test rom - 25FU406B -- I checked with its data sheet. Its 4M-bit (512K×8) Serial Flash Memory .It works between 2.3v to 3.6 V (2.5V is suggsested) . So I selected everything right but still I got overcurrent error and I was forced to stop further work.
I am of opinion now that I am making mistakes in connecting revealprog to pomona clips .
I tried 2 ways -
1) First I assumed all pins are sequential from 1 to 8 and attached corresponding pins on pomona clips -- that did not worked or may be that was right but due to high voltage selection process failed.
2) Then I took a continuty checker and verified which pin from revealprog 8 pin output connector belongs to which coloured cable pin and then matched that sequence. ( snaps of both methods are attached)
This time I selected SANYO and right model with 2.5V as VPP. but still revelprog is giving over current errors.
Now I think unless connections are done properly I will not be able to read any chips.
Digisupport / HaQue can you pls. correct me as you are using this model and must be familiar with pomona clip connections.
Is there list of all serial eproms used in hard disks so that I will make a excel sheet with corresponding voltages , manufactuere name etc.

Attachments

from pc3000.PNG (4.62 KiB) Viewed 20096 times

[labtech]

What is the full model on the EEPROM? 25xxxxx what?

[terminator2]

What is the full model on the EEPROM? 25xxxxx what?

Its SANYO 25FU406B

[labtech]

Type the model in the search box like in attached picture and should be good to go.
I use the normal ROM socket reader, as I cannot get the pomona clips to work either.

Attachments

[terminator2]

Type the model in the search box like in attached picture and should be good to go.
I use the normal ROM socket reader, as I cannot get the pomona clips to work either.

Hi labtech.
Thanks a lot.

[einstein9]

What is the full model on the EEPROM? 25xxxxx what?

Its SANYO 25FU406B

Is this Seagate 2.5"?
ST500LT012?

[terminator2]

No It was seagate Desktop hard disk. I dont remember exact model no. but could be either from 7200.12 / Barracuda drive.

[einstein9]

No It was seagate Desktop hard disk. I dont remember exact model no. but could be either from 7200.12 / Barracuda drive.

could you post here the PCB # ?

100xxxx

[terminator2]

hi einstein9
Here are pcb details. Unfortunately I dont have USB microscope so could not take magnified view.
IC no is 25FU406B

Attachments

25 Series Serial eprom.PNG (20.14 KiB) Viewed 19628 times