N2 EMMC AND ETHERNET notworking

[ziya]

Device: Odroid N2+ 4Gb / 32 Gb EMMC
Hello, I was trying to connect an UART module to the onboard UART socket of the N2+ then I guess I mistakenly shorted somewhere and my bootloader got corrupted. I downloaded the Petitboot (dev.20211112) Recovery image and flashed on an SD card then I powered the device with SPI/EMMC switch on the EMMC side. New petitboot is installed. When I re-powered the device with switch on SPI side Petit boot menu came. There I can make the necessary configuration. EMMC module is not recognized. I bought an EMMC card reader and flased Android on it. EMMC attached on the EMMC reader on the SD card slot worked fine. The system booted Android. Ethenet has gone although the link is up.
When EMMC is attached to the EMMC socket on the board and SD card inserted to the SD card slot petitboot doesn't see EMMC. Only mmcblk1 is recognized that is the SD card. Ethernet link is up. I search this issue and in some posts people suggest updating the u-boot.
I followed the instrustions on the link below
https://wiki.odroid.com/odroid-n2/softw ... ing_u-boot

At the final stage I'm stuck.
u-boot is writen on the blank sd card and ejected.

What am I supposed to do with this sd card? Shall I insert it to the sd slot of odroid with SPI/EMMC switched to EMMC and restart the device?
I tried this but nothing happened.
Any advice please?
Thanks in advance.
Ziya

[ziya]

Here below is the screen shot from my isntallation

[ziya]

Here below is the screen shot from my isntallation

[ziya]

Here below petitboot photos

[tobetter]

I doubt eMMC hardware on your N2 is damaged so it cannot access to eMMC if it does not appear in Petitboot. If so, updating U-Boot won't help you.

For sure, let's try this and share the result.

1. Flash Hardkernel's Ubuntu image to "SD" card.
2. Attach your eMMC to its slot on N2, no need to change or flash it.
3. Flip the boot select switch to "MMC" and do power cycle. So expecting to boot from SD.
4. In Ubuntu, check if "/dev/mmcblk0" exists or not. If not exists, eMMC slot is somehow does not work.

[ziya]

Hello Thank you for the reply. Attached the list of disks on the device.
Ethernet is also not working on the Ubuntu.
As you mentioned it's a hardware issue on the board.
I found this repair guide:
https://wiki.odroid.com/odroid-n2/hardware/repairs
I checkked the Q1 transistor. It looks fine by shape. Not blown like the pictures shown in the guide, but maybe it is still damaged.
Can replacing this Q1 transistor help?
Are there any test points on the board to verify if it is working properly or not by measuring voltages somewhere?

[ziya]

I checked the voltage on GPIO pin 1 and pin 17. They are 3.3V

[Moan]

Your petitboot isn't the newest available version. The newest version is: 20220317.

Try to update it as described here: viewtopic.php?p=362378#p362378

Then copy spiboot-20220317.img to the first partition of the same SD card as spiboot.img, so that update starts on next booting. Once the update is over, place the boot select switch to SPI and do power cycle again.

If you flash the Recovery image 20211112, then simply delete the existing spiboot.img file, paste spiboot-20220317.img and rename it to spiboot.img.

From my experience though, petitboot doesn't work good (or doesn't start at all) when eMMC is in the slot. I had to remove it each time in order to be able to use SPI.

By the way, if your Ethernet port is damaged, then maybe it's easier to buy a cheap USB Ethernet adapter? I recently upgraded my N2 to inexpensive 2.5Gbs Ethernet this way, and I can write with ~200MB/s and read with 130-160MB/s from USB HDDs. Obviously I use it as NAS so it's more needed, but you could also get just 1gb/s.

[ziya]

Hello Moan,
Thank you for the reply. I will repeat flashing as you described. Yes you are right, when EMMC is attached on the boardt, petitboot doesn't function well if EMMC is not accessible.
By the way, I read the repairs guide;

https://wiki.odroid.com/odroid-n2/hardware/repairs

and I checked the FK3407 mosfet if it is damaged or not. The mofset is damaged. I learnt how to check from a few youtube videos using a multimeter. As explained, these types of mosfets can be damaged even without showing any physical damage on the surface like burn outs. I will take the board to a repair shop for part replacement.
I will write the progress here
Thanks & have a good day