Quote:
Originally Posted by geekmaster
What serial adapter are you using? If it has a TX LED on it, you may need to remove that (or replace it with a suitable pull-up resistor) because the kindle TX pin cannot sink enough current to pull an LED-connected wire down to a logic zero (as described in my level-shifter thread).
And BTW, "SE Blank <xxx>" is typically known here is "USB downloader mode", so you may need a modern version of "MfgTool" (or other usb downloader tool) to flash your firmware. This mode does not to the serial port, as I understand it. It was probably triggered by a failed firmware update, so your firmware is now corrupted. This can be caused by updating the firmware on a kindle with a low battery (which depletes before completion).
Also, "eMMC destroyed" implies a hardware failure, when it is probably just the contents that are corrupted (due to incomplete firmware update), not the physical device. |
I'm using a FT232RL-based adapter with a 3.3 to 1.8V supply for the Vio (not using the kindle for that). It has LEDs, but they are driven by dedicated pins of the FT232RL, not directly connected to the TX/RX lines. I have measured voltages and they are correct (1.8V) and shorting RX to TX on the adapter also works. There is also an small chance that I shorted TX to GND while trying to check for an output as the pad in the KV is very close to the metal frame, so it is also possible that I have blown the output driver of the SoC as it should rest at 1.8V when idle and I can't measure any voltage on that pin.
It is also possible that when entering USB downloader mode the SoC set all its I/O pins as inputs, or disabled, but I don't know.
I mentioned the eMMC "destroyed" as it is explained by KNC1 on another post. Depending on when the supply fails the internal indexes of the eMMC may go wrong rendering the IC unusable (although I suposse it would be possible to read back from it). As it looks like UBOOT is not present (no output on the console even if I press a key during start-up) I assumed the whole eMMC has been erased or is failing.
I have downloaded the MfgTool2 that is supposed to support my device. I intend to follow the steps on the "PW2 eMMC upgrade" thread, but I need to build the uboot image to test and were wondering if someone could provide such an image to check if at least the device is recoverable.
Thank you very much for your answer. I'll try to build the image and check with MfgTool if I get something from the serial console port or I can flash fastboot.