Table of contents

RoadTest: Microchip SAMA5D2 (Rev. B) Xplained Ultra Evaluation Kit

Author: matfur92

Creation date: 5 Nov 2017

Evaluation Type: Development Boards & Tools

Did you receive all parts the manufacturer stated would be included in the package?: True

What other parts do you consider comparable to this product?: SAMA5D3 Xplained, Atmel SAMA5D4 Xplained Ultra, Arduino Yun, Raspberry Pi 3

What were the biggest problems encountered?: Poky Yocto with a package manager (ex: apt-get) Ubuntu or Debian working images already compiled and compatible with SDHC

Detailed Review:

Hi to all.

This is my review of SAMA5D2 (Rev. B) Xplained Ultra Evaluation Kit.

Let's we started with the unboxing :

As you can see the box contains only the board and one USB cable to connect it to the PC.
No paper manual is included, only a cardboard with some details regarding how and where is possible to find documentation and some files like drivers o SO images / demo .

To do a complete review of this board, my idea was to install OctoPrint enviroment, create a plugin for it that was able to read temperature from an attached sensor on Arduiono pins.

My first step was in order to install the Octoprint environment.

1) Install USB drivers for Atmel and Segger tools : https://gallery.atmel.com/Products/Details/6272a8fd-68fe-43d8-a990-741878cfe7b6

2) Open JP1 to enable EDBG

3) Close JP2 to disable de DEBUG port J1 (needed to avoid conflict on the UART TX line)

4) Connect the USB cable to the board (J14 EDBG-USB)

5) Install putty on my PC: https://www.chiark.greenend.org.uk/~sgtatham/putty/latest.html

6) On windows : Device management > Ports > EDBG Virtual COM Port (COM3) > Properties > Port Setting

    Baud rate    115200

    Data    8 bits

    Parity    None

    Stop    1 bit

    Flow control    None

7) Open putty serial session with the same settings

8) Type enter button on the console session to see :

Poky (Yocto Project Reference Distro) 2.0.1 sama5d2-xplained /dev/ttyS0
sama5d2-xplained login:

9) Type "root" to enter as root user.

10) Type "uname -a" to have more informations :

root@sama5d2-xplained:~# uname -a
    Linux sama5d2-xplained 4.1.0-linux4sam_5.3 #1 Sat Apr 16 10:19:57 CEST 2016 armv7l GNU/Linux
root@sama5d2-xplained:~# df -h
    Filesystem      Size  Used Avail Use% Mounted on
    /dev/root       939M  258M  634M  29% /
    devtmpfs        219M     0  219M   0% /dev
    tmpfs           251M  156K  251M   1% /run
    tmpfs           251M   96K  251M   1% /var/volatile
root@sama5d2-xplained:~# free -m
              total        used        free      shared  buff/cache   available
    Mem:            500           7         472           0          20         482
    Swap:             0           0           0
    
root@sama5d2-xplained:~# ifconfig
    eth0      Link encap:Ethernet  HWaddr fc:c2:3d:04:70:72
              UP BROADCAST MULTICAST  MTU:1500  Metric:1
              RX packets:0 errors:0 dropped:0 overruns:0 frame:0
              TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
              collisions:0 txqueuelen:1000
              RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
              Interrupt:33 Base address:0x8000

    lo        Link encap:Local Loopback
              inet addr:127.0.0.1  Mask:255.0.0.0
              UP LOOPBACK RUNNING  MTU:65536  Metric:1
              RX packets:10 errors:0 dropped:0 overruns:0 frame:0
              TX packets:10 errors:0 dropped:0 overruns:0 carrier:0
              collisions:0 txqueuelen:0
              RX bytes:700 (700.0 B)  TX bytes:700 (700.0 B)
    
root@sama5d2-xplained:~# python -V
    Python 2.7.9
    
root@sama5d2-xplained:~# pip -V
    pip 7.1.0 from /usr/lib/python2.7/site-packages (python 2.7)

11) Install virtualenv (prerequisite for OctoPrint)

curl -O --insecure https://pypi.python.org/packages/d4/0c/9840c08189e030873387a73b90ada981885010dd9aea134d6de30cd24cb8/virtualenv-15.1.0.tar.gz
tar xvfz virtualenv-15.1.0.tar.gz
cd virtualenv-15.1.0
python setup.py install
virtualenv --version

    With these commands the "15.1.0" version of virtualenv is installed

12) Install OctoPrint

date -s "05 NOV 2017 14:22:00"
mkdir octoprint
cd octoprint
wget --no-check-certificate https://github.com/foosel/OctoPrint/archive/master.zip
unzip master.zip
cd OctoPrint-master
pip install --trusted-host pypi.python.org autopep8 certifi
pip install --trusted-host pypi.python.org pip --upgrade
virtualenv venv    
./venv/bin/python setup.py install

At this point one thing block me to the next steps : the absence of the gcc compiler, it block the setup.py.

My intention was to install it from a repository, but I find no precompiled version ready to download. No Advanced Packaging Tool or something like that is present in this board. The only idea that I had was to make it :

On Sama :

mkdir gcc
cd gcc

On my PC (with Bash on Ubuntu on Windows):

wget http://ftp.it.debian.org/debian/pool/main/g/gcc-defaults/gcc_6.3.0-4_armhf.deb
ar x gcc_6.3.0-4_armhf.deb
tar xf data.tar.xz
tar -cvf gccArmV7.tar ./usr
scp gccArmV7.tar root@192.168.1.6:/home/root/gcc

On sama:

tar -xvf gccArmV7.tar

But at this point I was blocked by the space, the expand process was in error. This wasn't the correct way.

Frustrated by this point, I tryed to found a new way to have a more flexible environment. My choose was to get a working Ubuntu distro on Sama5D2 on a SDHC card of 8GB.

I found a splendid guide that, step-by-step, illustrated the wawy to create a working Ubuntu distro at http://www.eewiki.net/display/linuxonarm/SAMA5D2+Xplained+Ultra .

I followed this with some details on the steps:

ARM Cross Compiler: GCC

cd ~/
wget -c https://releases.linaro.org/components/toolchain/binaries/6.4-2017.08/arm-linux-gnueabihf/gcc-linaro-6.4.1-2017.08-x86_64_arm-linux-gnueabihf.tar.xz
tar xf gcc-linaro-6.4.1-2017.08-x86_64_arm-linux-gnueabihf.tar.xz
export CC=`pwd`/gcc-linaro-6.4.1-2017.08-x86_64_arm-linux-gnueabihf/bin/arm-linux-gnueabihf-
${CC}gcc --version

And the last response was :

arm-linux-gnueabihf-gcc (Linaro GCC 6.4-2017.08) 6.4.1 20170707
Copyright (C) 2017 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Bootloader: U-Boot

cd ~/
git clone https://github.com/u-boot/u-boot
cd u-boot/
git checkout v2017.09 -b tmp
wget -c https://rcn-ee.com/repos/git/u-boot-patches/v2017.09/0001-sama5dX-fixes.patch
patch -p1 < 0001-sama5dX-fixes.patch
make ARCH=arm CROSS_COMPILE=${CC} distclean
make ARCH=arm CROSS_COMPILE=${CC} sama5d2_xplained_mmc_defconfig
make ARCH=arm CROSS_COMPILE=${CC}

Linux Kernel

cd ~/
git clone https://github.com/RobertCNelson/armv7_devel
cd armv7_devel/

For v4.9.x-sama5-armv7 (Longterm 4.9.x):

git checkout origin/v4.9.x-sama5-armv7 -b tmp

For v4.14.x-sama5-armv7 (Longterm 4.14.x): <-- I selected this

git checkout origin/v4.14.x-sama5-armv7 -b tmp

Build

./build_kernel.sh

Root File System

Debian 9

debian|temppwd

root|root

cd ~/
wget -c https://rcn-ee.com/rootfs/eewiki/minfs/debian-9.2-minimal-armhf-2017-10-10.tar.xz
sha256sum debian-9.2-minimal-armhf-2017-10-10.tar.xz
31419dacdde26c62ea17670d262c01bc562881f5129b43b822c5de1286ba29d3  debian-9.2-minimal-armhf-2017-10-10.tar.xz
tar xf debian-9.2-minimal-armhf-2017-10-10.tar.xz

Ubuntu 16.04 LTS

ubuntu|temppwd

cd ~/
wget -c https://rcn-ee.com/rootfs/eewiki/minfs/ubuntu-16.04.3-minimal-armhf-2017-10-10.tar.xz
sha256sum ubuntu-16.04.3-minimal-armhf-2017-10-10.tar.xz
b9c56cc566978addd00e9187fbf19bea3f3ef9ac4256927451043341a9ca1ad6  ubuntu-16.04.3-minimal-armhf-2017-10-10.tar.xz
tar xf ubuntu-16.04.3-minimal-armhf-2017-10-10.tar.xz

Setup microSD card

For these instruction we are assuming, DISK=/dev/sdX, lsblk is very useful for determining the device id.

NOTE : I deleted all partitions on the SD card. The space was totally empty.

export DISK=/dev/sda

Create Partition Layout: With util-linux v2.26, sfdisk was rewritten and is now based on libfdisk.

sudo sfdisk --version
sfdisk from util-linux 2.27.1

If sfdisk >= 2.26.x <-- I selected this

sudo sfdisk ${DISK} --force <<-__EOF__
1M,48M,0xE,*
49M,,,-
__EOF__

If sfdisk <= 2.25.x

sudo sfdisk --unit M ${DISK} <<-__EOF__
1,48,0xE,*
49,,,-
__EOF__

Format Partition for DISK=/dev/mmcblk0 :

sudo mkfs.vfat -F 16 -n BOOT ${DISK}p1
sudo mkfs.ext4 -L rootfs ${DISK}p2

Format Partition for DISK=/dev/sdX :

sudo mkfs.vfat -F 16 -n BOOT ${DISK}1
sudo mkfs.ext4 -L rootfs ${DISK}2

Mount Partition:

sudo mkdir -p /media/boot/
sudo mkdir -p /media/rootfs/

Mount Partition for DISK=/dev/mmcblk0 :

sudo mount ${DISK}p1 /media/boot/
sudo mount ${DISK}p2 /media/rootfs/

Mount Partition for DISK=/dev/sdX :

sudo mount ${DISK}1 /media/boot/
sudo mount ${DISK}2 /media/rootfs/

Install Bootloader:

sudo cp -v ./u-boot/boot.bin /media/boot/BOOT.BIN
sudo cp -v ./u-boot/u-boot.img /media/boot/

Install Kernel and Root File System

To help new users, since the kernel version can change on a daily basis. The kernel building scripts listed on this page will now give you a hint of what kernel version was built.
Copy and paste that "export kernel_version=4.X.Y-Z" exactly as shown in your own build/desktop environment and hit enter to create an environment variable to be used later.

export kernel_version=4.14.0-rc4-sama5-armv7-r0

Copy Root File System

sudo tar xfvp ./*-*-*-armhf-*/armhf-rootfs-*.tar -C /media/rootfs/
sync
sudo chown root:root /media/rootfs/
sudo chmod 755 /media/rootfs/

Copy Kernel Image

sudo cp -v ./armv7_devel/deploy/${kernel_version}.zImage /media/boot/zImage

Copy Kernel Device Tree Binaries

sudo mkdir -p /media/boot/dtbs/
sudo tar xfvo ./armv7_devel/deploy/${kernel_version}-dtbs.tar.gz -C /media/boot/dtbs/

Copy Kernel Modules

sudo tar xfv ./armv7_devel/deploy/${kernel_version}-modules.tar.gz -C /media/rootfs/

File Systems Table (/etc/fstab)

sudo sh -c "echo '/dev/mmcblk1p2  /  auto  errors=remount-ro  0  1' >> /media/rootfs/etc/fstab"
sudo sh -c "echo '/dev/mmcblk1p1  /boot/uboot  auto  defaults  0  2' >> /media/rootfs/etc/fstab"

Remove microSD/SD card

sync
sudo umount /media/boot
sudo umount /media/rootfs

At thi point the SD was complete.

The first run had this response :

reading /dtbs/at91-sama5d2_xplained.dtb
30424 bytes read in 153 ms (193.4 KiB/s)
reading zImage
sdhci_transfer_data: Transfer data timeout
Error reading cluster
** Unable to read file zImage **
## Flattened Device Tree blob at 21000000
   Booting using the fdt blob at 0x21000000
   Loading Device Tree to 3fb58000, end 3fb626d7 ... OK

Starting kernel ...

..and nothing happened.

I try to change the SD with a SDHC and this was I saw: [look at sdHc1.log in attachment]

I try to change the SDHC with a SDHC that I had into the Raspberry Pi 3 and this was I saw: [look at sdHc2.log in attachment]

This is my actual situation and I still working on a fix for these problems.

My experience with this board is not very good. I can resume this with "frustrating" because the it is not a fast development board for my scopes.

I think that only if I need to run a python script or a c++ compiled app is very fast to use, but not if I want to have a different linux distro.

For me this is a new challange to do what I want with this board, but, If someone need to be very fast in development and need to have some alternatives distros, I suggest to use a more common board like the Raspberry Pi 3.

I think that this board is very customizable, as I can see into the documentation, but it have a few complicated setup to do it.

In my opinion a better step-by-step and simple documentation to do some operations [like build apps, change distro, configure pin-out] is very appreciated.

The compatibility with arduino mega shields is very impressive, as also the ARM Cortex-A5 and the pin-out for LCD monitor.

Thanks a lot for this opportunity of review

Matteo