I think my plt 8031 is bricked beyond simple repair. HELP!

djester631

Member
Jan 31, 2013
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So I have a plt 8031. I installed the drivers that I found somewhere (hours of searching). Anyway it showed up as a "RK29 device" in device manager. I ran a root tool that just ran through some adb commands and pushed superuser.apk. Then I installed clockworkmod using these instructions. How to install CWM-based Recovery for Rockchip | androtab.info
At this point I was rooted and could go into clockworkmod recovery not problems. I backup up the current rom and tried installing a Cyanogen unofficial. It didn't work, so I tried to restore.
Then it would only turn on and show the blue "Proscan" screen, but when connected to the computer while holding the menu button it still showed up as a RK29 device.
I plugged it in and let it charge overnight. Now I try to turn it on and it won't start at all. I don't even get the backlight turning on around the edges.
It does show up in windows as an unknown device.

Is there a way to just re-write the nand with a fresh img?
 
You can't really "hard brick" a RK29 device.

To restore your tablet back into a fully working state you either need a custom ROM that works on your tablet or you need a FULL "update.img" from your manufacturer.

The update.img (from your manufacturer) can be flashed through RKBatchTool with the tablet set into "bootloader mode" - or it can also be torn apart to make it fit for RKAndroid Tool flashing (easier to use than RKBatchTool).

As for the "shows up in Windows as an unknown device" ... you are most likely missing the "Flash mode" Rockchip USB driver, hence why Windows tells you it's an unknown device. Try updating the "Unknown device" by manually installing the Rockchip driver (pointing it to the drivers directory).

Anyway, try to find a FULL ROM update.img for your tablet first. Try contacting Proscan and ask them if they could provide you with it, in case it's not up for download. From there on out we'll surely find a way to restore the tablet back into a working condition.
 
I have the full img file from the Proscan site. So where do I get the "Flash Mode" usb driver? When I try to manually update the driver (using the one that I have), it tells me that it's not a valid driver.
 
I have the full img file from the Proscan site. So where do I get the "Flash Mode" usb driver? When I try to manually update the driver (using the one that I have), it tells me that it's not a valid driver.

I've put the Rockchip USB Driver onto MediaFire - should work with, more-or-less, all Rockchip 29xx devices.

There are a few special cases where you need to edit the driver INF files to add a specifc Vendor/Product ID, but I don't think this applies to Proscan tablets.

Of course you could also scan through the Proscan web site to try and see if they provide a driver ZIP for download.
 
Those appear to be the same drivers that I have already. To edit the inf, do I just load up the properties in device manager -> details -> Hardware Ids. Then add the ids there to the Rockchip.NTamd64 section as the %RK29_DeviceDesc% item?
 
Those appear to be the same drivers that I have already. To edit the inf, do I just load up the properties in device manager -> details -> Hardware Ids. Then add the ids there to the Rockchip.NTamd64 section as the %RK29_DeviceDesc% item?

Grab the driver INF for your OS ... i.e. Windows 7 x64 Edition.
Open it in Notepad or Notepad++

Add your device into the Rockchip.NTamd64 and Rockchip.NTx86 section this way...

Code:
%RKPLT8031_DeviceDesc%=Rockusb_DDI, USB\VID_2207&PID_290A
Replace the given VID and PID with the CORRECT VID and PID string for YOUR device!!!
The Windows Device Manager should show you that info in the details of the "Unknown Device"

In the Strings section you add...
Code:
RKPLT8031_DeviceDesc="Proscan PLT 8031 Device"

Once that driver is installed (and assuming your tablet actually is a RK28xx/RK29xx based device) RKAndroidTool and/or RKBatchTool should be able to access the device in Flash Mode.

EDIT: If modifying the driver doesn't work for whatever reason you better ask Proscan for the USB drivers for your device, though Google confirming that it's a RK2918 based device the generic Rockchip driver should actually work (after the modification).

On another note: Here (MediaFire folder) you can find some Rockchip Tools I pulled together from various places. Also contains a copy of the Rockchip Batch Tool 1.5 containing the RockUSBDriver (which should be the same as I linked you in my post above).
 
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EighthPieceOfNine, thanks for the help. I think I'm screwed though. The PID and VID are being returned as 0000. When I edit the inf, per your instructions, windows still refuses to believe that the driver will work.

Just to see what is going on I hooked it up to my linux laptop and this was in the dmesg output.
[ 120.292044] usb 2-3: new high-speed USB device number 2 using ehci_hcd
[ 135.404229] usb 2-3: device descriptor read/64, error -110
[ 150.620061] usb 2-3: device descriptor read/64, error -110
[ 150.836052] usb 2-3: new high-speed USB device number 3 using ehci_hcd
[ 165.366533] ehci_hcd 0000:00:1d.7: port 3 reset error -110

I'm not sure what it means, but it doesn't look too promising. Know of any more tricks that might miraculously save me?

(I did try different USB cables and have tried holding down the menu and vol up buttons when plugging it in.)
 
EighthPieceOfNine, thanks for the help. I think I'm screwed though. The PID and VID are being returned as 0000. When I edit the inf, per your instructions, windows still refuses to believe that the driver will work.

Just to see what is going on I hooked it up to my linux laptop and this was in the dmesg output.
[ 120.292044] usb 2-3: new high-speed USB device number 2 using ehci_hcd
[ 135.404229] usb 2-3: device descriptor read/64, error -110
[ 150.620061] usb 2-3: device descriptor read/64, error -110
[ 150.836052] usb 2-3: new high-speed USB device number 3 using ehci_hcd
[ 165.366533] ehci_hcd 0000:00:1d.7: port 3 reset error -110

I'm not sure what it means, but it doesn't look too promising.

Whoa... that really doesn't look too promising. Read errors on the USB connection and only "0000:0000" as the VID/PID isn't great (especially when it should be something along the line of 2207:000x

Know of any more tricks that might miraculously save me?
(I did try different USB cables and have tried holding down the menu and vol up buttons when plugging it in.)

There's only one more "trick" you can try... FORCE the tablet into Flash Mode...

1. Connect the charger to the tablet
2. Connect the USB cable to JUST the tablet
3. Power up your Linux laptop and prepare a terminal window
(Using Linux here is the better choice as we don't need a stupid driver to enumerate devices on the USB bus)
4. PRESS AND HOLD the VOL- button on the tablet
5. While KEEPING the VOL- button pressed push the reset button

You won't see ANY reaction on the tablet - no LCD, no sound
In case the LCD powers on repeat it till it stays "dead" (then it's in USB Flash mode)

6. Connect the tablet to your Linux laptop
7. In the terminal, do a
lsusb -v

LONG output to follow ... copy/paste the whole output to i.e. pastebin and link it here for review.

The difference to your attempt is that this procedure makes the tablet break boot completely and hop into the "Flash mode" (which is more like a USB JTAG/UART mode). At that stage only the CPU and the first-stage loader (obviously "hard coded" into the CPU's NVRAM) is running - it does nothing more than to init the hardware, init the eMMC (NAND) and setup the USB download connection. At this stage there is NO kernel booted or any part of the system loaded ... we're as low-level in the hardware init as it gets.

IF the computer is seeing the tablet in Flash mode you can flash-back by using RKAndroid Tool (requires Windows - and the Rockchip driver for the "RK29xx device" to talk to the Tablet in flash mode), though for that to happen your update.img needs to be taken apart and made fit for RKAndroid Tool flashing. We get to that as soon as we verified the tablet is still showing signs of life in "forced" Flash mode; if that works you better send me your update.img so I can create you a pre-made RKAndroid Tool package where everything's set up.
 
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I followed the instructions. dmesg had this when I plugged in the tablet.
[ 6172.912061] usb 2-1: >new high-speed USB device number 2 using ehci_hcd
[ 6188.024059] usb 2-1: >device descriptor read/64, error -110
[ 6203.240036] usb 2-1: >device descriptor read/64, error -110
[ 6203.456072] usb 2-1: >new high-speed USB device number 3 using ehci_hcd
[ 6218.568066] usb 2-1: >device descriptor read/64, error -110
[ 6233.784065] usb 2-1: >device descriptor read/64, error -110
[ 6234.000061] usb 2-1: >new high-speed USB device number 4 using ehci_hcd
[ 6244.408060] usb 2-1: >device not accepting address 4, error -110
[ 6244.520069] usb 2-1: >new high-speed USB device number 5 using ehci_hcd
[ 6254.928075] usb 2-1: >device not accepting address 5, error -110

Here's the output of lsusb -v
lsusb -v output - Pastebin.com

It doesn't look promising, but I appreciate you having a look.
 
I followed the instructions. dmesg had this when I plugged in the tablet.
(snip)

Plugged in to the computer in WHAT state? Normal USB connection (read: tablet turned on and letting it just hang there wherever the boot may fail) OR in flash mode (VOL- / Reset Button to force it into Flash/Bootloader mode)?

EDIT: Googling around for a minute: Depending on the manufacturer there's also a pretty good change that you may have to press VOL+ / Reset to set the tablet into the desired mode (or any other fancy combination). Seems as conformity is not in the books of hardware vendors. If it doesn't work with VOL- / Reset you have to try for a bit. Like I said ... the intended result is that the tablet stays "dead" but reports itself in flash mode on the USB bus (2207:0006 or something around that VID/PID combo). Easiest way to work it out is to connect it via USB and doing a "lsusb" (without the -v to keep the output brief) after each try to see if it showed up ... and maybe running a 'tail -f /var/log/syslog' in another terminal to have an eye on the system messages regarding the USB connection.

If the USB errors come from the tablet being connected in flash mode ... are you 101% sure the USB cable is ok, there's no hardware problem with the USB ports on the tablet or computer and that you didn't plug the cable into a USB hub (I don't see a USB hub listed in your lsusb output, but just for safety)?

Here's the output of lsusb -v
lsusb -v output - Pastebin.com

It doesn't look promising, but I appreciate you having a look.

Not entirely surprisingly, given the USB errors from above, the tablet isn't even listed on the bus.

This means we're back to square one:

- Check the USB cable you are using (maybe use another one if you have a spare sitting around)
- Check there's no hardware problem with the µUSB port on the tablet or the USB port on your laptop
- Check the cable is directly connected to an USB port on the laptop (NO hub in between)
- Check you connect the tablet in Flash/Bootloader mode

If you can rule out everything from above it looks like you did the impossible and managed to wreck the primitive loader (which is responsible for turning the tablet into flash mode) somehow.

Looking at your initial description about what you did, you shouldn't have managed to terminate the tablet. While putting together CWM I also flashed the one or another borked recovery.img, and the worst thing that happened was that normal system boot simply failed. Hell, I even already once flashed a kernel.img containing a kernel that wasn't really working ... showed a lot of garbled junk on the screen but didn't cause any troubles either. Back to Flash mode, flash back to the stock kernel, voila, works again.

Let's see if you are tempted to give the troubleshooting one more go.
 
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I set up a terminal window running 'watch -n 1 lsusb' and another with 'watch -n tail /var/log/syslog'. Then I proceeded to hold each button while pressing reset, then plugging it into the laptop. Every time the syslog said the same error along the lines of "new high speed USB device n on port 1.... blah blah blah... -101". Then I tried a the key combos I could think of. Menu with Vol-, Menu with Vol+ etc. Then I switched usb cables. Nothing seemed to work. I think I'm done. I appreciate the help.
 
Yap, seems that is it. If you can't get it back onto the USB bus there's no chance of flashing the firmware back in.

Sorry, but that's where I'm out of options. I never found any documentation about the RK29xx devices detailing the possibility of UART/JTAG-port based unbrick methods or providing some worthwhile board schematics. Unless you find someone knowing how to bring it back from the dead by tapping into the hardware you're out of options here.
 
Wait, I just discovered something. If you hold the menu button down, hit power for about 3 seconds and continue holding the menu button you will get a droid with an exclamation point in a red triangle. ADB devices command shows the device is in recovery mode. If I'm correct you can flash from adb recovery mode.
 
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