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Yocto Linux BSP Ver.B User Guide

Introduction​

This document describes how to obtain, build, customize, and recover Advantech’s Yocto 3.3 (hardknott) BSP for i.MX8-based platforms.

Getting Started

Building Yocto Image — System Requirements​

  • CPU Cores: Quad‑core processor (or higher recommended)
  • Memory: 8 GB RAM (more is recommended for better performance)
  • Disk Space: 350 GB (SSD recommended for better performance)

Conventions​

  • \${PREBUILT_IMAGE} — compressed prebuilt image (*.img.gz)

  • \${CONTAINER_NAME} — container name (e.g. imx8LBVB0016)

  • \${BSP_TARBALL} — BSP tarball (*.tgz)

  • \${BSP_HOME} — home directory of the BSP

  • \${BDIR} — build directory (e.g. build_x11)

  • \${MX8PROC} — i.MX8 processor

    • mx8mq for i.MX8M Quad/Dual
    • mx8mm for i.MX8MM
    • mx8mp for i.MX8MP
    • mx8qm for i.MX8QM
    • mx8qxp for i.MX8QXP

  • \${IMX8PROC} — shorthand processor string: imx8mq / imx8mm / imx8mp / imx8qm / imx8qxp

  • \${BOARD} — available targets: rom5720 rom5721 rom7720 rom5620 rom3620 rom5722 rsb3720

  • \${BOARD_REV} — board revision, e.g. a1

  • \${MC} — machine code combined as \${IMX8PROC}\${BOARD}\${BOARD_REV}
    Examples:

    • imx8mqrom5720a1 (ROM‑5720 A1)
    • imx8qmrom7720a1 (ROM‑7720 A1)
    • imx8qxprom5620a1 (ROM‑5620 A1)
    • imx8qxprom3620a1 (ROM‑3620 A1)
    • imx8mmrom5721a1 (ROM‑5721 A1)
    • imx8mprom5722a1 (ROM‑5722 A1)
    • imx8mprsb3720a1 (RSB‑3720 A1)

    You can also list supported machines:

    $ source setup-environment

  • \${MEM_SIZE} — memory size, e.g. 2G / 4G

  • \${UC} — U‑Boot config, e.g. 1G / 2G / 4G / FSPI_1G / FSPI_2G …

  • \${SD_DEVICE} — device name of SD card in Linux (e.g. /dev/sdf)

  • \${SDCARD_IMAGE} — sdcard image built by bitbake (*.wic.bz2)

  • \${WORKSPACE} — host workspace folder

  • \${UBOOT} — U‑Boot version (e.g. 2016.03)

  • \${KERNEL} — Linux kernel version (e.g. 4.14.98)

  • \${TOOLCHAIN} — toolchain install dir (e.g. /opt/fsl-imx-x11/4.1.15-2.0.0)

Debug/serial console: use a serial terminal (minicom/putty/teraterm …) at 115200 8N1.
Terminal console: any terminal program (gnome‑terminal, xfce4‑terminal …).

Docker install and settings​

If you don’t have Docker, please install it first (refer to the Docker Engine installation guide).

Pull base image​

$ docker pull advrisc/u18.04-imx8lbv1

Create container​

$ docker run --privileged -it --name ${CONTAINER_NAME} \
  -v ${WORKSPACE}:/home/adv/adv-release-bsp \
  -v /dev:/dev advrisc/u18.04-imx8lbv1 /bin/bash

Get BSP​

You can either download from GitHub via repo, or copy a BSP tarball into the container.

Download BSP from GitHub​

For example, using official tag imx8LBVB0209:

$ git config --global user.name "Your Name"
$ git config --global user.email you@example.com
$ sudo chown adv:adv adv-release-bsp
$ cd adv-release-bsp
$ repo init -u git://github.com/ADVANTECH-Corp/adv-arm-yocto-bsp.git \
  -b refs/tags/imx8LBVB0209 -m imx8LBVB0209.xml
$ repo sync

Other BSP manifests​

5.10.35‑2.0.0:

$ repo init -u git://github.com/ADVANTECH-Corp/adv-arm-yocto-bsp.git \
  -b imx-linux-hardknott -m imx-5.10.35-2.0.0.xml
$ repo sync

5.10.72‑2.2.0:

$ repo init -u git://github.com/ADVANTECH-Corp/adv-arm-yocto-bsp.git \
  -b imx-linux-hardknott -m imx-5.10.72-2.2.0.xml
$ repo sync

If you see “server certificate verification failed” with self‑signed certs:

$ export GIT_SSL_NO_VERIFY=1
# or
$ git config --global http.sslverify false

If you see “The unauthenticated git protocol on port 9418 is no longer supported.”:

$ git config --global url."https://".insteadOf git://

Copy BSP tarball to container​

If you already have a BSP tarball (e.g. imx8LBVB0029_2021-10-23.tgz):

  1. Exit the container
$ exit
  1. Copy tarball to \${WORKSPACE} and fix ownership
$ cp imx8LBVB0029_2021-10-23.tgz ${WORKSPACE}
$ sudo chown adv:adv ${WORKSPACE}/imx8LBVB0029_2021-10-23.tgz
  1. Back to container
$ docker start ${CONTAINER_NAME}
$ docker attach ${CONTAINER_NAME}
  1. Unpack
$ tar zxvf imx8LBVB0029_2021-10-23.tgz

Yocto will create a downloads/ during build, but fetching may fail occasionally. Using a prepared downloads tarball can help.

  • Example: downloads_imx8_5.10.35.tar.gz (md5: 912999faf861bf413cef4cf7a9f18dfa)

Steps:

  1. Exit container
$ exit
  1. Copy tarball to \${WORKSPACE} and fix ownership
$ cp downloads_imx8_5.10.35.tar.gz ${WORKSPACE}
$ sudo chown adv:adv ${WORKSPACE}/downloads_imx8_5.10.35.tar.gz
  1. Back to container
$ docker start ${CONTAINER_NAME}
$ docker attach ${CONTAINER_NAME}
  1. Unpack and link
$ tar zxvf downloads_imx8_5.10.35.tar.gz
$ cd adv-release-bsp
$ ln -s ${WORKSPACE}/downloads_imx8_5.10.35 downloads

Introducing the BSP​

The BSP is based on the Yocto Project with NXP/Freescale enhancements for i.MX8, and Advantech board support.

Key items:

  • sources/ — Yocto layers (community + Advantech)
  • meta-advantech/ — Advantech meta layer
  • meta-fsl-* — NXP/Freescale meta layers
  • fsl-setup-release.sh — create a new build env
  • setup-environment — continue an existing env
  • One or more build directories

Naming rule​

  • BSP tarball: imx8LBVA0010_2019-08-27.tgz

    • LB = Linux BSP
    • VA0010 = Version A 0010

  • Prebuilt image: 5720A1AIM20LIVA0010_iMX8M_2G_2020-08-27.img.gz

    • 5720A1 = ROM‑5720 A1
    • LI = Linux Image
    • 2G = DDR size

BSP content​

  • sources/**
    • meta-advantech/ — Advantech layer
    • meta-fsl-* — NXP/Freescale layers
  • fsl-setup-release.sh — new build env
  • setup-environment — continue env

Build Instructions​

Create a new build environment​

$ cd ${BSP_HOME}
$ MACHINE=${MC} DISTRO=fsl-imx-xwayland \
  source imx-setup-release.sh -b ${BDIR}

Specify default U‑Boot config:

$ MACHINE=${MC} UBOOT_CONFIG=${UC} DISTRO=fsl-imx-xwayland \
  source imx-setup-release.sh -b ${BDIR}

Accept the EULA when prompted.
Accept EULA

Continue an existing build environment​

$ cd ${BSP_HOME}
$ source setup-environment ${BDIR}

Build SD card image​

$ bitbake imx-image-full

The output imx-image-full-${MC}.wic.bz2 will be under ./tmp/deploy/images/${MC} when finished.

Build toolchain installer​

$ bitbake meta-toolchain

The installer will be under ./tmp/deploy/sdk, e.g.
fsl-imx-xwayland-glibc-x86_64-meta-toolchain-aarch64-toolchain-${KERNEL}-zeus.sh

Build bootloader​

$ bitbake imx-boot

Build Linux kernel​

If you’re in Docker, install tmux first:

$ sudo apt-get update && sudo apt-get install -y tmux
$ tmux

Kernel menuconfig:

$ bitbake linux-imx -c menuconfig

Exit tmux window after editing:

$ exit

Build kernel image:

$ bitbake linux-imx

Artifacts Image and Image-${IMX8PROC}-${BOARD}-${BOARD_REV}.dtb will be under ./tmp/deploy/images/${MC}.

Creating boot-up on-board flash from prebuilt image​

Create a bootable SD card​

# gunzip -c ${PREBUILT_IMAGE} | sudo dd of=${SD_DEVICE} bs=1M
# sync

Creating boot-up on-board flash from built SD card image​

Create a bootable SD card​

$ pushd ${BSP_HOME}/${BDIR}/tmp/deploy/images/${MC}
$ sudo bzcat ${SDCARD_IMAGE} | sudo dd of=${SD_DEVICE} bs=1M
$ sync
$ popd

Debug console information​

Hardware​

Please refer to your board’s debug UART header and cable mapping (Debug Port Information).

Software​

Use a serial terminal such as minicom or putty with 115200 baud.

One-step build image​

Docker must be preinstalled.

Download helper script:

$ wget https://raw.githubusercontent.com/ADVANTECH-Corp/RISC_tools_scripts/hardknott/imx8/adv_imx8_build.sh
$ sudo chmod a+x adv_imx8_build.sh

Build image:

$ sudo ./adv_imx8_build.sh ${BOARD}
# Example
$ sudo ./adv_imx8_build.sh rom5720

Result images:

workspace/${BDIR}/tmp/deploy/images/${MC}

Then follow Creating boot-up on-board flash from built SD card image.

Customization

Package addition​

Add tcf-agent & openssh-sftp-server​

$ cd ${BSP_HOME}/sources/meta-advantech/meta-fsl-imx/recipes-fsl/images
# Edit fsl-image-adv.inc and append:
IMAGE_INSTALL += " tcf-agent openssh-sftp-server "

Add Chromium browser​

Edit local.conf under ${BSP_HOME}/${BDIR}/conf.

Method 1 (recommended)

CORE_IMAGE_EXTRA_INSTALL += "chromium-ozone-wayland"

Method 2

IMAGE_INSTALL_append = "${@bb.utils.contains('DISTRO_FEATURES', 'wayland', ' chromium-ozone-wayland libexif', \
    bb.utils.contains('DISTRO_FEATURES', 'x11', ' chromium-x11 libexif', '', d), d)}"
LICENSE_FLAGS_WHITELIST = "${@bb.utils.contains('DISTRO_FEATURES', 'wayland', 'commercial', \
    bb.utils.contains('DISTRO_FEATURES', 'x11', 'commercial', '', d), d)}"

Add QtWebEngine​

# ${BSP_HOME}/${BDIR}/conf/local.conf
IMAGE_INSTALL_append += " packagegroup-qt5-webengine "

Setting up SDK​

Build the SDK installer (see above), then run it:

$ cd ${BSP_HOME}/${BDIR}/tmp/deploy/sdk
$ sudo ./fsl-imx-xwayland-glibc-x86_64-meta-toolchain-aarch64-toolchain-5.4-zeus.sh

Follow prompts and wait until the SDK finishes installing.
SDK Install

Setting up cross-compiling environment​

$ source ${TOOLCHAIN}/environment-setup-aarch64-poky-linux

Build U‑Boot in a standalone environment​

Configure U‑Boot​

$ make ${IMX8PROC}_${BOARD}${BOARD_REV}_${MEM_SIZE}_defconfig
# Example
$ make imx8mm_rom5721a1_2G_defconfig

Build U‑Boot​

$ make -j$(nproc)

Build imx-boot image with imx-mkimage​

Obtain the imx-boot tarball (example for ROM‑5721):

$ tar zxvf 5721A1AIM20LIVA0118_iMX8MM_imx-boot.tgz
$ cd 5721A1AIM20LIVA0118_iMX8MM_imx-boot/
# Copy necessary files to imx-mkimage folder
$ ./cp_uboot.sh <uboot_path> ${IMX8PROC}
# Make imx-boot image
$ ./mk_imx-boot.sh ${IMX8PROC}
# Example
$ ./cp_uboot.sh ../uboot-imx6 imx8m
$ ./mk_imx-boot.sh imx8mm

Replace imx-boot​

Write to on‑board flash:

$ sudo dd if=flash.bin of=/dev/mmcblk0 bs=1K seek=<offset> conv=fsync

Offsets:

  • 33 — i.MX 8QuadMax A0, i.MX 8QuadXPlus A0, i.MX 8M Quad, i.MX 8M Mini
  • 32 — i.MX 8M Plus, i.MX 8QuadXPlus B0/C0, i.MX 8QuadMax B0

Build & update kernel/modules/DTB manually​

Assumes cross env is sourced (see Setting up cross‑compiling environment).

Unpack kernel tarball in container​

$ sudo chown adv:adv imx8LBVA0029_2019-10-23_linux-imx.tgz
$ tar zxvf imx8LBVA0029_2019-10-23_linux-imx.tgz

Configure kernel​

$ cd linux-imx
$ make distclean
$ make imx_v8_adv_defconfig
$ make menuconfig

Build kernel​

$ make -j$(nproc) Image

If you hit link errors like the screenshot, try:

$ unset LDFLAGS

The kernel Image will be at ./arch/arm64/boot/.

Build modules​

$ make -j$(nproc) modules
$ make modules_install INSTALL_MOD_PATH=~/temp/rootfs

Build DTB​

$ make -j$(nproc) freescale/${IMX8PROC}-${BOARD}-${BOARD_REV}.dtb
# Example
$ make -j$(nproc) freescale/imx8mq-rom5720-a1.dtb

DTB will be at ./arch/arm64/boot/dts/freescale/.

Replace kernel & DTB​

Copy Image and DTB to your SD/eMMC boot partition as needed.

Improve boot speed​

Bootloader​

  1. Boot delay
u-boot> setenv bootdelay 0
u-boot> saveenv
u-boot> reset
  1. Disable console messages (quieter kernel)
u-boot> setenv mmcargs setenv bootargs ${jh_clk} console=${console} \
    modprobe.blacklist=${modprobe.blacklist} root=${mmcroot} \
    video=HDMI-A-1:${videores} quiet
u-boot> saveenv
u-boot> reset

Or disable debug port entirely:

u-boot> setenv console
u-boot> saveenv
u-boot> reset

Services​

Disable unneeded services:

$ sudo systemctl disable <service>
# e.g.
$ sudo systemctl disable boottimes

System Recovery

Restore eMMC image if the on‑board system is corrupted.

Recovery by SD card​

  1. Copy 5720A1AIM20LIVA0022_iMX8M_flash_tool.tgz to your PC.
  2. Insert SD card.
  3. Make a bootable SD:
# tar zxvf 5720A1AIM20LIVA0022_iMX8M_2G_flash_tool.tgz
# cd 5720A1AIM20LIVA0022_iMX8M_2G_flash_tool/mk_inand/
# sudo ./mksd-linux.sh /dev/sdg
  1. Copy 5720A1AIM20LIVA0022_iMX8M_flash_tool to a USB disk.
  2. Insert USB disk + SD card and boot from SD.
  3. From the USB disk, flash eMMC:
# cd /run/media/sda1/
# cd 5720A1AIM20LIVA0022_iMX8M_2G_flash_tool/mk_inand/
# sudo ./mksd-linux.sh /dev/mmcblk0

Recovery by UUU tool​

  1. Download UUU: https://github.com/ADVANTECH-Corp/uuu/releases/tag/v20200619
  2. Run:
# Linux
$ sudo ./uuu
# Windows
> uuu.exe
  1. Prepare a folder containing:
1. uuu
2. imx-boot-imx8mqrom5720a1-sd.bin-flash_evk
3. fsl-image-validation-imx-imx8mqrom5720a1-20190917152605.rootfs.sdcard
4. Image_dtb.uuu
5. rootfs.uuu
  1. Connect OTG cable PC ↔ device.
  2. Set boot mode (e.g. ROM‑5720/5721/5620: 1,2,3=off 4=on, ROM‑7720: 1,2,3,4,5,6=off or 1,2,4,5,6=off 3=on) and power on.
  3. Example burn commands (U‑Boot ≥ 2019‑11‑01 for writing to mmcblk0):
# 1) Burn U‑Boot to eMMC
## a) replace U‑Boot in mmcblk0boot0
$ sudo ./uuu -b emmc imx-boot-imx8mqrom5720a1-sd.bin-flash_evk
## b) replace U‑Boot in mmcblk0
$ sudo ./uuu -b emmc_adv imx-boot-imx8mqrom5720a1-sd.bin-flash_evk

# 2) Burn rootfs image to eMMC
## a) with U‑Boot in mmcblk0boot0
$ sudo ./uuu -b emmc_all imx-boot-imx8mqrom5720a1-sd.bin-flash_evk \
  fsl-image-validation-imx-imx8mqrom5720a1-20190917152605.rootfs.sdcard
## b) with U‑Boot in mmcblk0
$ sudo ./uuu -b emmc_all_adv imx-boot-imx8mqrom5720a1-sd.bin-flash_evk \
  fsl-image-validation-imx-imx8mqrom5720a1-20190917152605.rootfs.sdcard
  1. To update only kernel/DTB via UUU:
# Rename files
_Image
_board.dtb
# Then
$ sudo ./uuu Image_dtb.uuu
  1. To update only rootfs via UUU:
# Rename rootfs tarball
_rootfs.tar.bz2
# Then
$ sudo ./uuu rootfs.uuu
  1. Fastboot method (UUU >= 1.4.139)
# In U‑Boot
u-boot> fastboot 0
# From host
$ sudo uuu -b fat_write Image mmc 0:1
$ sudo uuu -b fat_write xxx.dtb mmc 0:1

More usage: https://github.com/NXPmicro/mfgtools/wiki

Package List

List all packages built into the image:

$ bitbake -g fsl-image-qt5-validation-imx \
  && cat recipe-depends.dot | grep -v -e '-native' | grep -v digraph \
  | grep -v -e '-image' | awk '{print $1}' | sort | uniq

(2019‑10‑25 Package List)

Show all recipes (including non-installed):

$ bitbake -s

(2019‑10‑25 Package Version List)

You can also check:

${BDIR}/tmp/deploy/images/${MC}/fsl-image-qt5-validation-imx-${MC}.manifest

On target board, list packages by rpm:

$ rpm -qa --root / --dbpath /var/lib/rpm | sort

(2019‑10‑25 RPM on Board List)

Device Tree Source file select

Choose DTB in U‑Boot to enable different devices, e.g.:

u-boot> setenv fdt_file adv-imx8mm-rom5721-a1-dsi2dp.dtb
u-boot> saveenv
u-boot> boot

ROM‑5721​

Display​

  • DSI to LVDS
    • imx8mm-rom5721-a1.dtb (g070vw01)
    • imx8mm-rom5721-a1-dsi2lvds-g150xgel05.dtb (g150xgel05)
    • imx8mm-rom5721-a1-dsi2lvds-g215hvn01.dtb (g215hvn01)
  • DSI to DP
    • imx8mm-rom5721-a1-dsi2dp.dtb
  • DSI to HDMI
    • imx8mm-rom5721-a1-adv7535.dtb
  • DSI (panels)
    • imx8mm-rom5721-a1-auog101uan02.dtb (auog101uan02)
  • M.2 SDIO
    • imx8mm-rom5721-a1-m2-sdio.dtb (adjust CN43~CN48)

ROM‑5720​

Display​

  • DSI to HDMI
    • imx8mq-rom5720-a1-dcss-adv7535.dtb
    • imx8mq-rom5720-a1-lcdif-adv7535.dtb
    • For Weston UI, set drm-device=card2 in /etc/xdg/weston/weston.ini
  • DSI (panel)
    • imx8mq-rom5720-a1-dcss-auog101uan02.dtb (auog101uan02)
  • Dual Display (DSI->HDMI + HDMI)
    • imx8mq-rom5720-a1-dual-display.dtb
    • For Weston UI, set drm-device=card1
  • M.2 SDIO
    • imx8mq-rom5720-a1-m2-sdio.dtb (adjust CN43~CN48)

ROM‑5620​

Display​

  • LVDS
    • imx8mxp-rom5620-a1.dtb (g070vw01)
    • imx8qxp-rom5620-a1-lvds-chimei.dtb (g150xgel05)
    • imx8qxp-rom5620-a1-lvds-dual.dtb (g215hvn01)
  • LVDS to HDMI
    • imx8qxp-rom5620-a1-hdmi-bridge.dtb
  • DSI to HDMI
    • imx8qxp-rom5620-a1-hdmi-bridge.dtb
  • DSI (panel)
    • imx8qxp-rom5620-a1-auog101uan02.dtb (auog101uan02)
  • M.2 SDIO
    • imx8qxp-rom5620-a1-m2-sdio.dtb (adjust CN43~CN48)

ROM‑7720​

Display​

  • HDMI
    • imx8qm-rom7720-a1.dtb
  • LVDS
    • imx8qm-rom7720-a1-lvds0.dtb (g070vw01)
    • imx8qm-rom7720-a1-lvds1.dtb (g070vw01)
    • imx8qm-rom7720-a1-lvds-dual.dtb (g215hvn01)
  • HDMI + LVDS
    • imx8qm-rom7720-a1-hdmi-lvds0.dtb (HDMI + g070vw01)
    • imx8qm-rom7720-a1-hdmi-lvds1.dtb (HDMI + g070vw01)
    • imx8qm-rom7720-a1-hdmi-lvds-dual.dtb (HDMI + g215hvn01)
  • LVDS to HDMI
    • imx8qm-rom7720-a1-it6263.dtb
  • Audio Codec
    • imx8qm-rom7720-a1-sgtl5000.dtb

RSB‑3720​

Display​

  • HDMI (default)
    • imx8mp-rsb3720-a1.dtb
  • LVDS + HDMI
    • imx8mp-rsb3720-a1-lvds0-auo.dtb (g070vw01 LVDS0 + HDMI)
    • imx8mp-rsb3720-a1-lvds1-auo.dtb (g070vw01 LVDS1 + HDMI)
    • imx8mp-rsb3720-a1-lvds-dual.dtb (g215hvn01 dual LVDS + HDMI)
  • DSI
    • imx8mp-rsb3720-a1-adv7535.dtb (DSI->HDMI) + HDMI
    • imx8mp-rsb3720-a1-auog101uan02.dtb (DSI) + HDMI

Camera​

  • OV5640 (default): imx8mp-rsb3720-a1.dtb
  • Basler: imx8mp-rsb3720-a1-basler.dtb

ROM‑5722​

Display​

  • HDMI (default): imx8mp-rom5722-a1.dtb
  • LVDS + HDMI
    • imx8mp-rom5722-a1-lvds0-auo.dtb (g070vw01 LVDS0 + HDMI)
    • imx8mp-rom5722-a1-lvds1-auo.dtb (g070vw01 LVDS1 + HDMI)
    • imx8mp-rom5722-a1-lvds-dual.dtb (g215hvn01 dual LVDS + HDMI)
  • DSI
    • imx8mp-rom5722-a1-adv7535.dtb (DSI->HDMI) + HDMI
    • imx8mp-rom5722-a1-auog101uan02.dtb (DSI) + HDMI

Camera​

  • OV5640 (default): imx8mp-rom5722-a1.dtb
  • Basler: imx8mp-rom5722-a1-basler.dtb

ROM‑3620​

Display​

  • LVDS
    • imx8mxp-rom3620-a1.dtb (g070vw01)
    • imx8qxp-rom3620-a1-lvds-chimei.dtb (g150xgel05)
    • imx8qxp-rom3620-a1-lvds-dual.dtb (g215hvn01)
  • DSI to HDMI
    • imx8qxp-rom3620-a1-hdmi-bridge.dtb
  • DSI (panel)
    • imx8qxp-rom3620-a1-auog101uan02.dtb (auog101uan02)

Burn‑in Test

Read MAC, Serial Number, Manufacture Date from QSPI​

Note: Adjust /dev/mtdblock0 and offsets for your platform.

MAC 0

READ_DATA=$(dd if=/dev/mtdblock0 bs=1 skip=$((0xd0000)) count=6 2>/dev/null | hexdump -e '6/1 "%02x:" "\n"' | sed 's/:$//')
echo "$READ_DATA"

MAC 1

READ_DATA=$(dd if=/dev/mtdblock0 bs=1 skip=$((0xd0400)) count=6 2>/dev/null | hexdump -e '6/1 "%02x:" "\n"' | sed 's/:$//')
echo "$READ_DATA"

Serial Number

READ_DATA=$(dd if=/dev/mtdblock0 bs=1 skip=$((0xd0006)) count=10 2>/dev/null)
echo "$READ_DATA"

Manufacture Date (formatted as YYYY-MM-DD_hh-mm-ss)

RAW=$(dd if=/dev/mtdblock0 bs=1 skip=$((0xd0010)) count=14 2>/dev/null)
READ_DATA="$(echo "$RAW" | cut -c1-4)-$(echo "$RAW" | cut -c5-6)-$(echo "$RAW" | cut -c7-8)_$(echo "$RAW" | cut -c9-10)-$(echo "$RAW" | cut -c11-12)-$(echo "$RAW" | cut -c13-14)"
echo "$READ_DATA"