I have some Question about install the Ubuntu on the our custom board

Hello. I have some question about “Jetson Nano SDMMC3”

We designed the Jetson Nano Carrier Board at our purpose.

(We attached the MicroSD Socket on the our custom Carrier Board using SDMMC3 Signal.)

1. I'm asking if I can install Ubuntu on a MicroSD Card connected to SDMMC3. -> we don't need Jetson Nano eMMC(16GByte), Because it is very small storage.
  1. If it is possible, i want know about how to install.

  2. I am wondering if it is possible to change the Jetson Nano OS boot order.
    -> If it is possible about install the ubuntu OS in SDMMC3 MicroSD Card,
    I want to change the First boot order priority to MicroSD Card and the Second boot order priority to eMMC.

Sorry for late reply. We are still checking this and I will share the answer soon.

Thanks for your patience.

i got it! I really appreciate about your kindles.

Hi yoonju,

Jetson nano is using the u-boot so you could check the boot-order by printenv in uboot console.

Hello!
we did it.

1. we fusing the kernel at Jetson Nano module (with eMMC). => Fusing kernel is "SDMMC3" Enable. 2. We program system.img to MicroSD (64GByte). => Using the "Jetson-disk-image-creator.sh" maked the system.img. 3. Starting the first boot with emmc, i fixed eMMC's extilunx.conf. => Modification is "root=/dev/mmcblk1p1" => mmcblk0p1 is eMMC => mmcblk1p1 is MicroSD 4. finally We confirmed the microSD normal booting.

We attached the MicroSD file system screenshot.
i wondering if there is anything wrong.

Please screenshot check please.
IMG_7302.jpg
IMG_7300.jpg
IMG_7301.jpg
IMG_7303.jpg

Hi,

Your method would read kernel from emmc but use the rootfs in sdcard. Your screenshot looks as expectation.

hello!

Yes!, You are right.

We using the kernel in eMMC, and rootfs is sdcard.

Can i use it like this?

SDcard seems to be unable to use both kernel and rootfs. Because the default kernel is SDMMC3 disable.

and jetson Nano Module using the SDMMC4 emmc so we must programming emmc.

so I have enabled SDMMC3 I/F in dtb. I used SDMMC3 as rootfs.

Hi yoonju,

We using the kernel in eMMC, and rootfs is sdcard.

Can i use it like this?

Sure.

SDcard seems to be unable to use both kernel and rootfs. Because the default kernel is SDMMC3 disable.

I am wondering uboot is able to detect the sdmmc4 or not. You could try to remove the extlinux.conf and Image from your emmc and see if u-boot goes to search the one on sdcard.

1 Like

Hi,

We’ve verified the function that you could fully use the kernel and rootfs from sdmmc w/o emmc.

Please refer to this thread and use the uuid method.
https://devtalk.nvidia.com/default/topic/1060950/jetson-tx2/how-can-we-flash-everything-apart-bootloader-to-extern-sdcard-on-tx2-like-jetson-nano-with-no-intern-/post/5373638/#5373638

i got it!

I really appreciate about your kindles.

I’m so thank you