Help! Proper way to short a FlashRAM IC to clear it?

Discussion in 'General Electronics Chat' started by Mugsy, May 1, 2018.

  1. Mugsy

    Thread Starter New Member

    May 1, 2018
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    Long story short, I need to clear the Winbond FlashRAM (pdf pg 7) chip in my tablet to reset the Bios.

    I found information online that suggests I can do this by grounding one of the pins, but before I attempt this, I could use some advice. What's the best way to "ground" an IC to discharge it?

    I was thinking of simply using needlenose tweezers to link the required pin to Pin-4 (labeled "Ground" in the schematic.)

    Would it be better to "ground" it to something else? Should I use low-gauge wire instead of steel tweezers for this (does it matter)? Does the tablet need to be On to do this? I have a multi-meter and was wondering if I could use it to perform this?

    Any information is appreciated. TIA
     
  2. Mugsy

    Thread Starter New Member

    May 1, 2018
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    I need to reset a Winbond FlashRAM (pinouts on pdf pg 7) chip in my tablet to reset the Bios.

    According to Winbond, below is the proper sequence of steps one must perform to manually reset/clear it, but it's mostly over my head. What do I do here? Apply charges to the pins? How? How much charge and for how long? Can this even be done by hand? I definitely don't want to damage anything.

    The steps they gave me:

    ===================
    First of all, you have to convert from /hold pin to /reset pin. you have to write the status register-3 for that.
    Please read the SR3 first with 15h. I think it should be 60h or something else. If it’s 60h, you have to change it to E0h with 11h command.

    Here is the write status register-3 sequence.
    06h (Write Enable)
    11h (Write SR3)
    E0h (SR3 value)
    Wait for BUSY bit clear or ~15ms after /CS high.
    15h (Read SR3).
    ===================

    Any help is appreciated.

    MOD:
    Post Merged with Existing Thread
     
    Last edited by a moderator: May 2, 2018
  3. dl324

    AAC Fanatic!

    Mar 30, 2015
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    Welcome to AAC!

    You should contact the tablet manufacturer to see if the tablet supports a reset under tablet control. If it doesn't, you'd have to remove the device to erase.

    If you attempt to do it in-circuit, the device needs to be powered; which will power up other tablet circuitry that will fight for control of the FLASH device.
     
  4. MrSoftware

    Well-Known Member

    Oct 29, 2013
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    We need some context. Are you trying to use a typical user method of resetting the BIOS to get back to factory defaults? I think you may be looking at the wrong thing. Possibly there is a jumper on the computer motherboard to be shorted to reset the BIOS (this is common), this would most likely be in the manual somewhere. It's very unlikely they would expect any normal user to fiddle with individual chips.

    If you are sure that you need to erase the actual chip; The instructions you received about writing to the registers is how to talk to the chip and tell it to erase itself. Normal people don't have the tools or knowledge to do this so I don't think this is what you're after. But if this is your goal, then look at the chip datasheet and determine the interface (probably SPI). You need to connect the proper pins to a device that can communicate with the chip, then write some code to send the commands. Or get your hands on a device that is pre-programmed to do this. Basically you send a command to enable writing, then send a command to erase. There are multiple erase commands so be sure to send the one you want (sector erase, whole chip erase, etc..). The chip datasheet will have all of the details. As mentioned above, it's going to be difficult to do this with the chip still on the board, but I don't think this is really what you want to do anyway.
     
  5. Mugsy

    Thread Starter New Member

    May 1, 2018
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    I've been avoiding the ugly details b/c people seem to get side-tracked asking me questions I've already answered dozens of times elsewhere, asking if I've done this or tried that or performed some obvious basic step first, and of course I have.

    I have a UEFI-based Windows-10 tablet ("Insignia", Best Buy's home brand) with detachable keyboard. I was trying to get it to boot from a USB flash drive.

    I got into the BIOS and (of course) I first tried changing the boot order, but it didn't work. So then I tried modifying some other USB settings, but to get access to them, I had to disable the XHCI Controller (unaware this would disable USB support.) When I rebooted, my detachable keyboard no longer worked, nor did anything else plugged into the USB ports. :eek:

    I can get back into Bios easily. But w/o a keyboard, I can't navigate beyond the first page to make any changes (the Volume up/down keys on the tablet only act as up/down, and the Power button acts as the Enter key. I need Left/Right keys.)

    I could (past tense) log into Windows using the on-screen keyboard, but there was no way to reset my Bios settings from within Windows (I searched Google for hours looking for a solution.) The closest thing to an answer I could find was the blog posting I linked to in my first post, and a few sites claiming you can reset the bios from a Linux terminal.

    I first tried clearing the bios as shown in the linked graphic, but the chip is "locked". Even desoldering the battery leads didn't clear the bios.

    So I turned to trying to figure out how to install Linux entirely from Windows. But no only did the attempt fail, but it installed a Boot Loader menu that doesn't support a touch-screen and also requires Left/Right keys to navigate. So now I can't even get back into Windows! :(

    So I'm back to trying to clear the Bios FlashRam chip by hand to reset the Bios back to its defaults and reenable my USB ports.

    (And before anyone asks, No, there is no Reset button on the tablet. I'm not an idiot. Best Buy's "Geek Squad" knows less than I do. Insignia took 72 hours to answer one question.)

    That's where things stand. Any help anyone can provide is appreciated.
     
  6. Papabravo

    Expert

    Feb 24, 2006
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    For the record nobody has made any disparaging comments. That said, what you are asking is a highly unusual. Unless someone had actual experience with the exact make and model of your system they might be more than a bit reluctant to offer advice which could end up turning your laptop into a brick. You might want to cut the folks trying to help just a little bit of slack. Just because a way exists to do what you want with the chip in isolation, does not mean it is a practical method of doing what you want to a chip installed on a powered up motherboard.
     
  7. Mugsy

    Thread Starter New Member

    May 1, 2018
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    I'm not accusing anyone of making "disparaging comments", only becoming easily sidetracked... like this. :(

    And the "exact make & model of my computer" is irrelevant since the IC in question is in general use in millions of portable electronics.

    And since my tablet (not laptop) is presently little more than a lighted serving tray at this point, the threshold for what I'm willing to risk is much lower.

    I've been asking for help on multiple forums, and *every time*, when I go into the "long story", THIS happens and no progress is made, so you can understand why I was so reluctant. :(
     
  8. Raymond Genovese

    Active Member

    Mar 5, 2016
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    I hear your frustration, but please keep some context in mind. You are in a jam (because of your own actions) and you are at the point where... "Any help is appreciated". Given that set of circumstances, I think it is incumbent upon you to be tolerant of all suggestions that are given. This is a small price to find that one bit of information that will help you, even if it all the rest of the advice is of little value to you - given the predicament.

    That being said, I do not have specific instruction for clearing the Windbond chip and I do NOT think that is the way for you to go at this time. There are two reasons why I feel this way:

    1) You have absolutely no idea how to clear the chip when it is installed in the system and are relying on the datasheet information which is not assuming it is already installed in your system. Additionally, you don't know what effect it is going to have if you are successful (what good would it be if all locations were reset to 0xff, for example). Why would you automatically think it would reinstall the BIOS as you want?

    2.) Since these systems are designed to be able to upgrade a BIOS, that is the way to proceed if you have failed to reinstall all factory settings.

    I spent a little bit of time searching the issue and found this thread which may be relevant: http://community.insigniaproducts.c...ows-Tablet-Original-UEFI-BIOS/m-p/90001#M3490

    Since you are reluctant to provide the model number of your unit, I am assuming that it is or is at least close to the NS-P11W7100.

    In the thread it is suggested, by someone in a predicament similar to yours, that you can re-write the BIOS from a file on an SD card. "It's my understanding that I can rename the file to AMIBOOT.ROM and it should automatically flash from an SD Card."

    Another respondent posted the BIOS file from their machine as requested.

    Risky? Yes. Riskier than shorting chips on the board when you don't have a solid idea that it will help? No, not in my view.

    Beyond that, I was struck by the function that you can reinstall factory settings - that seemed to reinitialize the BIOS. Perhaps you can't get there from where you are at.

    Finally, the specialized forum that I linked to is definitely a place to post your problem.

    Hope this helps.

    Edited to add: I see that you have already posted on that support board...and to no avail. Can you let us know if the BIOS file works or the results of whatever you end up doing?
     
    Last edited: May 3, 2018
  9. Mugsy

    Thread Starter New Member

    May 1, 2018
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    Thx for the reply. I don't feel I've been intolerant of any "useful" suggestions, but "Papabravo" lecturing me and offering nothing of assistance is exactly what I was trying to avoid.

    I'm not trying to "reinstall" the Bios, I'm simply trying to reset it back to it's default settings... something that is easily done if you can navigate to the final "Save/Exit" page of the Bios. But since I can't without a keyboard, I must find another way.

    And yes, I *did* try to find a way to "upgrade" (re-flash) the Bios, but recall two things: 1) this is a UEFI bios, so it has security features to make this.more difficult. 2) All I had access to was Windows, at most the Safe-Mode CLI. And Windows (especially Win10) has security layers to insulate you from making low-level changes to the Bios. And 3) Most significantly, I no longer have the ability to run ANY program, so there is no way to "upgrade the Bios" (even if it were possible, since if you recall, this all began with me trying to find a way to boot from USB. Most "Bios updates" are installed from a USB boot drive. I presently have no functioning USB ports... that's why I'm here... and was never able to boot from USB to begin with. So your suggested "way to proceed" is not an option.)

    Now, can we get back to my original question? :(
     
  10. Raymond Genovese

    Active Member

    Mar 5, 2016
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    Sure, we can get back to your original question. But why all the questions about such a simple procedure??? You already posted a picture of the reset procedure using leads. You know what pin you want to ground. You also have posted a picture of your board (on the other site). You have a gnd pin immediately to the left of your chip. Why not simply disconnect one lead from your multi meter and use that to make the connection?

    What could go wrong? :)
     
  11. Mugsy

    Thread Starter New Member

    May 1, 2018
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    Tried it. Didn't work.
     
  12. Raymond Genovese

    Active Member

    Mar 5, 2016
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    Oh well. So, I am thinking...

    When you say "I presently have no functioning USB ports". That is not true since your Keyboard is USB and it does work, just not the left-right (or was it up-down). Can you connect a USB mouse and see if you can get further within the factory reset procedure? Have you already tried that?

    Also, I am thinking that you may not have configured the USB device to boot correctly. There is a long thread about that here http://community.insigniaproducts.c...-boot-from-USB/m-p/90794/highlight/true#M3660

    The idea being that your BIOS is correctly set to boot from USB but your USB device is not set up right. Could you revisit that issue? I note though, that I would expect it to go to the next device if it can't find a USB boot device, so maybe you did brick the BIOS somehow.

    Have you gone deep into the keyboard to see if there are other combinations that might substitute for the two that you are missing? Maybe you did that already as well? I mean heck, you could, theoretically, program the key steps to mimic the path to resetting using another device.

    Got to be some ways to avoid settling on a new nightlight.
     
  13. Mugsy

    Thread Starter New Member

    May 1, 2018
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    (Sigh) No it doesn't. If it did, I wouldn't be in this mess. "Up/Down" refers to the tablet's Volume buttons, not the keyboard.

    Can I please just re-stipulate (as I did previously) that "I'm not an idiot"? I tried to reflash the bios (not possible from Windows), there is no Reset button, the only buttons on my tablet don't allow me to navigate through the bios, and I tried the method demonstrated in the link I shared.
     
  14. MrSoftware

    Well-Known Member

    Oct 29, 2013
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    This is a 64Mbit chip, I suspect that chip contains the entire BIOS (not only the "settings') and if you "erase" the chip then you will be left with a brick for a computer until the chip is reprogrammed with valid BIOS. UNLESS there is another chip holding factory BIOS somewhere on the board. Looking at the pictures you linked in the first post, the method to "reset' the bios from those pictures is just shorting the data-out pin on the chip, essentially making it impossible for the computer to read from it. What you could try is keeping that DO pin shorted to ground while you attempt to boot the computer. This will prevent the computer from being able to read data from the chip, and if there is a factory default copy of the BIOS stored elsewhere then maybe it will boot from it.

    I could be completely mistaken in my thinking and maybe that chip does hold only the settings, in which case keeping the DO pin shorted to ground very possibly could cause it to fall back to some defaults, but 64Mbit seems like a very big chip for only holding the "settings".

    Edit --> For clarity; briefly shorting the DO pin on that chip to ground is not a way to "erase" the chip, but keeping the DO pin shorted to ground should prevent the computer from being able to read from it.
     
    Mugsy likes this.
  15. Raymond Genovese

    Active Member

    Mar 5, 2016
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    You are right. I don't know why I assumed it was a USB keyboard. It is simply an attachable/detachable keyboard.

    I accept your stipulation that you are determined to work on the WB chip...for better or for worse.

    You provided a pic on the other site http://community.insigniaproducts.c...-USB-ports-Can-t-reset-bios-to-get/td-p/91385 The WB chip looks accessible and removable.

    Remove the WB chip and erase/clear/read/write etc.. yourself. Use an Arduino with this library https://github.com/Marzogh/SPIFlash/releases/tag/v3.1.0

    It says that it has been tested with a W25Q64FV which is a 3V version. You have a W25Q64FW which is a 1.8V version, so you will have to do some level shifting.

    Resolder the WB chip back on your tablet...
     
  16. Raymond Genovese

    Active Member

    Mar 5, 2016
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    Yeah, that was something I had also considered...that erasing the chip could leave you with a bricked board. As you stated, however, there are a number of "unlesses". I would add to that the possibility of writing the BIOS himself using a, presumably, good copy available from this thread http://community.insigniaproducts.c...ows-Tablet-Original-UEFI-BIOS/m-p/90001#M3490 for example.
     
  17. Mugsy

    Thread Starter New Member

    May 1, 2018
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    The keyboard IS a USB keyboard. That is why it doesn't work. It does not plug into the USB port though. It has it's own 7-contact connector on the bottom of the tablet that also acts as a pass-through for two USB-2.0 ports built into the keyboard. The tablet itself has a lone USB-3.0 Type-C port on it that likewise is disabled.

    The instructions provided to me by Winbond (see second post) are for using an EEPROM programmer to set the "/Reset" condition on the chip and clear the saved settings w/o erasing the Bios. The step that stands out most is getting pin-7 (/Hold, /Reset) to toggle to make clearing the Cmos possible.

    What you say about the method other people used... shorting the "DO" pin making the settings unreadable... sounds reasonable, though note I previously tried booting with "DO" shorted, and the keyboard remained disabled. I didn't try any others pins though. A friend had to desolder/resolder the power wires for me because my soldering skills suck. So removal of the chip is something I'm unlikely to attempt. :(

    Even if I did successfully remove it, I don't have a programmer to reset it using the method described by Winbond. And the likelihood of me bricking the tablet attempting to remove the chip it about 75% (and 85% putting it back.)

    I'm wondering if I would need to apply a small charge to the "/Reset" pin to toggle it, and if so, could that be done with a multimeter (to avoid destroying it with an uncontrolled shock?) Then maybe grounding Pin "DO" would work?
     
  18. Raymond Genovese

    Active Member

    Mar 5, 2016
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    OK, it is a USB keyboard and on the keyboard you have a couple of pass-thru USB ports and a separate USB-C port on the tablet itself. Got it...I even looked at the manual for a bit.

    You are not comfortable removing the chip and replacing it after erasing and, you don't want to (or can't because you don't have one) set up an arduino as a programmer.

    "I'm wondering if I would need to apply a small charge to the "/Reset" pin to toggle it, and if so, could that be done with a multimeter (to avoid destroying it with an uncontrolled shock?) Then maybe grounding Pin "DO" would work?"

    I don't know what that means...small charge...uncontrolled shock...that stuff.

    The instructions in your post #2 are clearly for programming the chip. You either take the chip out and program it, or you try to program it in the circuit.

    In either case, as far as those instruction in post #2 go, that looks like SPI programming to me and there is no way around that that I can see.

    Grounding D0 did not seem to work. That does not surprise me because if it did, it would be a very easy way to defeat any password that had been set in BIOS....and hopefully, those days are long gone.

    I remember spending a ton of hours programming a W25Q64FV on a Galileo and using another Galileo to do it. But, in that case, there was a DEDIPROG port specifically designed so that you could program the flash with power off to the board. You supplied VCC, GND, MOSI, MISO, SCK [forgot CS] directly to the chip. This works because it is designed to allow in-circuit programming.

    I don't know if programming the chip would work by leaving the chip on the board and with power to the tablet off and attaching the connections to the chip to allow an external programmer to work. It might, or it very much might not. In any case, you would need an SPI programmer. That was why I suggested the Arduino library that would be about the cheapest programmer. You would still have to do some delicate soldering to get those connections to the programmer.

    As frustrated as you are, by your own admission, you set the BIOS to boot from USB and when that didn't work, you changed some USB settings. Even if you don't remember what settings you changed, is there anything about the possible settings for USB that you might have set.? The idea being that you might still be able to affect a USB boot. Not what you want to hear, but I don't know what else to say.

    Maybe someone else has some other approach, but that is all I have.
     
    Last edited: May 3, 2018
  19. Mugsy

    Thread Starter New Member

    May 1, 2018
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    Since an IC works by sending minuscule electrical charges to the pins to toggle circuits between 0 & 1 (off/on) states, I'm wondering if I could do that "manually" using a multimeter?

    If the Bios software can reset the chip without removing it and with power connected/on, I should be able to as well.

    Not quite. All I did (first) was change the USB "Boot Order". And even though the setting exists in Bios, I *now* know UEFI does not "natively" support booting from an external drive. :(

    The source of all these problems is that they used a Bios not designed for touch-screen tablets in a touch-screen tablet. :mad:

    I do. As noted in my first reply to "MrSoftware", I disabled the XHCI Controller. The USB settings beneath it were disabled and I had to disable the controller to get access to them, not knowing that despite enabling the subsettings, the USB controller would remain disabled. :(

    I don't see any way of doing anything through the USB ports so long as the controller is disabled.

    Another long-shot "possibility" that has been floating in the back of my mind is... since the Volume up/down & Power buttons are capable of sending "keyboard commands" (up/down & Enter) to the Bios, I'm wondering if there isn't a way to transmit "left/right" keyboard inputs to the computer the same way? But I haven't a clue where to begin to pursue something like that. :confused:
     
  20. Raymond Genovese

    Active Member

    Mar 5, 2016
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    Thanks for clearing all that up for me and good luck with your problem.
     
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