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August 5, 2019 by Jean-Luc Aufranc (CNXSoft) - 2 Comments

How to Decode Markings on FBGA Memory Chips

SDRAM chips often come in compact FBGA (Fine-Pitch Ball Grid Array) packages, which do not leave enough space to write the full part number. So instead component manufacturers rely on abbreviated part markings that often have nothing to do with the actual part numbers. For example, the Micron SDRAM chip above has markings that read “PPE39 7LW75 D9WDL”. We know it’s a Micron part because of the logo, but if you search any on the number on the chip, you won’t find anything on the web. Instead, you need to look for the marking decoder from the chip company. Micron calls it the FBGA and Component Marking Decoder. Usually we need to use the second number on the chip, but in that case, it did not work, and I had to use the third number. I got my answer. Somehow the company does not link to any product page. Searching […]

July 26, 2019July 26, 2019 by Jean-Luc Aufranc (CNXSoft) - 21 Comments

How to Overclock Raspberry Pi 4 to 2.0 GHz

Yesterday I played with my new “ICE Tower CPU cooling fan” for Raspberry Pi 4 which cools the board just great but is clearly over the top. Regular reader and commenter m][sko mentioned it was possible to overclock Raspberry Pi 4 to 2.0 GHz after a firmware upgrade. That looks like a perfect task for my new fansink! I’ve upgraded both the firmware and operating system:

sudo rpi-update
sudo apt dist-upgrade

1 2	sudo rpi-update sudo apt dist-upgrade

then edited /boot/config.txt as root (sudo) to add the following lines to boost the maximum frequency to 2.0 GHz:

force_turbo=0
arm_freq=2000
over_voltage=6

force_turbo=0

arm_freq=2000

over_voltage=6

Do not try to set force_turbo=1, as while it would allow to further boost the voltage, it will change a fuse in the chip, and it will void your warranty. We can now reboot the board to validate the settings, and check those are applied:

vcgencmd get_config int | grep "arm\|over"
arm_freq=2000
over_voltage=6

vcgencmd get_config int | grep "arm\|over"

arm_freq=2000

over_voltage=6

Good. At idle the frequency is lower, but that normal:

vcgencmd measure_clock arm
frequency(48)=666826176

1 2	vcgencmd measure_clock arm frequency(48)=666826176

Voltage is set to 1.0335V:

vcgencmd measure_volts
volt=1.0335V

1 2	vcgencmd measure_volts volt=1.0335V

[…]

July 17, 2019July 17, 2019 by Jean-Luc Aufranc (CNXSoft) - 39 Comments

Checking Out Machine Check Exception (MCE) Errors in Linux

I recently reviewed ODROID-H2 with Ubuntu 19.04, and noticed some errors messages in the kernel log of the Intel Celeron J4105 single board computer while running SBC-Bench benchmark:

[180422.405294] mce: [Hardware Error]: Machine check events logged
[180425.656449] mce: [Hardware Error]: Machine check events logged
[180483.582825] mce_notify_irq: 17 callbacks suppressed
[180483.582827] mce: [Hardware Error]: Machine check events logged
[180484.991484] mce: [Hardware Error]: Machine check events logged
[180594.700684] mce_notify_irq: 13 callbacks suppressed
[180594.700686] mce: [Hardware Error]: Machine check events logged
[180858.202115] mce: [Hardware Error]: Machine check events logged
[181178.047031] mce: [Hardware Error]: Machine check events logged

[180422.405294] mce: [Hardware Error]: Machine check events logged

[180425.656449] mce: [Hardware Error]: Machine check events logged

[180483.582825] mce_notify_irq: 17 callbacks suppressed

[180483.582827] mce: [Hardware Error]: Machine check events logged

[180484.991484] mce: [Hardware Error]: Machine check events logged

[180594.700684] mce_notify_irq: 13 callbacks suppressed

[180594.700686] mce: [Hardware Error]: Machine check events logged

[180858.202115] mce: [Hardware Error]: Machine check events logged

[181178.047031] mce: [Hardware Error]: Machine check events logged

I did not know what do make of those errors, but I was told I would get more details with mcelog which can be installed as follows:

sudo apt install mcelog

1	sudo apt install mcelog

There’s just one little problem: it’s not in Ubuntu 19.04 repository, and a bug report mentions mcelog is not deprecated, and remove from Ubuntu 18.04 Bionic onwards. Instead, we’re being told the mcelog package functionality has been replaced by rasdaemon. But before looking into the utilities, let’s find out what Machine Check Exception (MCE) is all about from ArchLinux Wiki: A machine check exception (MCE) is an error generated by the CPU when the CPU detects that a hardware error or failure has occurred. Machine check exceptions (MCEs) can occur for a variety […]

July 1, 2019October 20, 2019 by Jean-Luc Aufranc (CNXSoft) - 15 Comments

Khadas VIM3 Review – Part 1: Kit Unboxing and Assembly

We started to read about Khadas VIM3 in May of this year as an Amlogic S922X development board with an M.2 socket for NVMe SSD, and 802.11ac WiFi 5 & Bluetooth 5.0 wireless module. Eventually, Shenzhen Wesion decided to change the processor to Amlogic A311D before the launch last month, since it does not cost much more, but includes a 5.0 TOPS neural processing engine. The company has sent me a Khadas VIM3 kit for evaluation and review. Before going through the software part, and especially the tools for the NPU which will be one of the highlights of the board, I’ll check out what I received today, and show how to assemble the kit. Khadas VIM3 Kit Unboxing The package is rather boring… But what’s really important is what’s inside… We’ve got an enclosure, a smaller package with the board itself, a USB-C power supply, a thermal pad + […]

June 24, 2019July 17, 2019 by Jean-Luc Aufranc (CNXSoft) - 8 Comments

ODROID-H2 Rev B Review – Part 1: Kit Unboxing and Assembly

ODROID-H2 was announced in October 2018 as the first x86 SBC from Hardkernel. The board features an Intel Celeron J4105 Gemini Lake processor, two SO-DIMM slots for memory, two SATA ports and M.2 NVMe slot for storage, two Gigabit Ethernet ports, a mix of USB 3.0 and 2.0 ports, as well as HDMI and DisplayPort video outputs. The board went for sale the following month for $111, and the first batch of 2,000 boards was sold within 24 hours. In normal cases, this should not be a big problem, and in a few weeks, the company should have been able to produce more boards to fulfill the demand. But Intel decided to prioritize higher-end processors, and Gemini Lake SoCs’ manufacturing was put on the back foot. That means Hardkernel had to wait over 6 months to get supply of the Celeron J4150 processors. In the meantime, the company slightly redesign […]

June 22, 2019June 28, 2019 by Jean-Luc Aufranc (CNXSoft) - 20 Comments

Create Minimal Debian Upstream Images with Debos and Armbian

Debos Armbian Debian Orange Pi Zero Plus 2 H5

[Update June 28: Post updated with correct procedure thanks to Collabora help] Armbian provides lightweight Debian or Ubuntu images for various Arm Linux SBC, and over the years has become the recommended source for stable firmware images for boards part of Orange Pi & Banana Pi families, and others. Uncompressed images are still over 1GB and come with Armbian-specific tools, kernel and bootloader. If you’d like to leverage Armbian images, but instead create a Debian upstream image with only the packages you intend to use, Collabora explains how to do just that with Orange Pi Zero +2 H5 and Libre Computer AML-S905X-CC (aka Le Potato) boards using Debos Debian OS builder. I’ve decided to give a try at the instructions for Orange Pi Zero Plus2 H5 in my laptop running Ubuntu 18.04 to better understand how this all works. I’ll assume you’ve already installed Docker, and made sure you’ve got […]

May 13, 2019April 25, 2021 by Jean-Luc Aufranc (CNXSoft) - 4 Comments

Customize Amazfit Bip Smartwatch – Thai Language and Mickey Mouse

I’ve been wearing WeLoop Hey 3S smartwatch for well over a year now, and I’m still very satisfied with it, but a small problem is that it does not support the Thai language, so when I receive messages it’s just blank, or only shows the ASCII characters part of the string. There’s also no real community for this watch, so customization options are limited, and readers recommended Amazfit Bip instead. I’ve writing about this, because one person I know looked for a smartwatch, and first wanted to get an Apple Smartwatch, but where I live it’s over one month of the minimum salary and around two to three weeks of a typical office salary. So instead I recommended the much cheaper Amazfit Bip after I was told the requirements were support for Thai language notifications, and custom watch faces in order to install a Mickey Mouse watch face, and both […]

May 3, 2019 by Jean-Luc Aufranc (CNXSoft) - 32 Comments

Enabling Two-Factor Authentication for SSH Access in Armbian

Until today, I only knew of two authentication methods for SSH: the traditional username/password and key-based login with private/public keys with the latter being more secure and not requiring any password. But I’ve just found out it’s also possible to login to SSH using two-factor authentication relying on your smartphone to get an OTP code like you would to access some banking services as it can easily be enabled in Armbian. First you’ll want to enable key-based login with private/public keys, or you won’t be able to access your board anymore after enabling 2FA except via the serial console. Now simply start armbian-config, and go to System Settings->Reconfigure SSH daemon to enable PhoneAuthentication “mobile phone one-time passcode”. We’re not done yet, so don’t close Armbian-config You’d then need an Android or iOS phone running Google Authenticator app to receive the OTP (one-time password). After enabling PhoneAuthenticator in armbian-config, you’ll see […]