09-02-2022, 07:10 PM
Disconnect all connections except power and serial console.
(If there is a connection to the USB-Port, disconnect that as well.)
1) Disable SPI (shorting pins 25+23 or 25+21). (shorting pins 25+23 or 25+21)
2) If eMMC is installed, disable it with a jumper pin.
In this state, write an image that has been confirmed to boot to the SD-CARD and boot.
(There is no need to remove the SPI jumper during the boot process.)
If you get a readable message on the serial console, you may be able to recover.
If, unfortunately, you get nothing at all from the serial console,
Try pressing the reset button several times, and the situation may change.
If there is no change in the situation after several tries, there is little hope of recovery.
(If there is a connection to the USB-Port, disconnect that as well.)
1) Disable SPI (shorting pins 25+23 or 25+21). (shorting pins 25+23 or 25+21)
2) If eMMC is installed, disable it with a jumper pin.
In this state, write an image that has been confirmed to boot to the SD-CARD and boot.
(There is no need to remove the SPI jumper during the boot process.)
If you get a readable message on the serial console, you may be able to recover.
If, unfortunately, you get nothing at all from the serial console,
Try pressing the reset button several times, and the situation may change.
If there is no change in the situation after several tries, there is little hope of recovery.
