Inside the Thermotalk Plus

The thermotalk plus by Miniland Baby is a clinical IR thermometer with pulse reading. The main features are:

  • Ultra-quick thermometer with infrared temperature measurement in 1 second.
  • Measures body pulse in just 15 seconds.
  • Communicates measurements by voice through its LCD display.

The thermotalk opens from the bottom just removing four screws. Inside, a single board contains all the electronics. In the top-down view, you can see some interesting components.

First off, an infrared temperature sensor. This type of sensor will transform the infrared light into an electric current. This electric current is then measured by an amperage or voltage detector.

Secondly, a segmented LCD display that is used to show the temperature and various other information. The display is connected to the circuit board directly, without connectors.

Finally, there is the speaker usedto communicate measurements in different languages.

The circuit board looks a two-layer board with green solder mask and white silkscreen on both sides. The PCB is comprised of surface-mount components and some through hole electrolytic capacitors.

The brains of the thermometer is a microprocessor that is die-mounted to the circuit board. A dome of black epoxy is used to keep it in place. It is most likely a custom IC designed especially for this application.

Attached to this microcontroller is a 24C08 EEPROM that most likely saves calibration constants and settings. The EEPROM is in a SOIC-8 package.

And on one tip of the board, there is a Biometric Pulse Rate or Heart Rate detecting sensor.

After disassembling, there are some components to reuse:

  • Segmented LCD display
  • IR temperature sensor
  • Speaker
  • EEPROM
  • Heart rate sensor
  • Mechanical button

OpenSUSE on a Lenovo Yoga 530 14IKB

The Three Wise Men bring me a new Lenovo Yoga 530 14IKB. As this will be a shared computer I need both operating systems installed, Windows and Linux. After finishing the Windows 10 setup, I decided to give openSUSE Tumbleweed a try.

First of all, you should get the installation media for your desired Linux and prepare a USB stick for the installation. For openSUSE Tumbleweed you can download a network installation image from ‘https://software.opensuse.org/distributions/tumbleweed’

To have some space for Linux, I’ve reduced the Windows partition to about 256GB so that Linux has about 256GB too. To do that you have to do the following steps in Windows:

  • Right-click Computer on the desktop, choose Manage.
  • Select Storage > Disk Management.
  • Right-click the partition that you want to reduce, select Shrink Volume.
  • Edit the proper size for the new partition, then click Shrink.

To boot from the USB stick rather than the Windows partition, you have to press F12 at boot time. Choose the prepared USB stick and boot into the openSUSE Linux installer.

Unfortunately wifi didn’t work out of the box in the live environment, so I had to insert a USB to LAN adapter.

The default installation options worked for me, just I took special attention at the disk partitioning step to make sure didn’t break the Windows 10 installation.

After all, OpenSUSE has been installed to the spare partition, the bootloader has been installed to the EFI partition and a boot entry for Windows has been created. Awesome.

UPDATE 2019/01/30

  • Athough the installation when fine I had a high CPU load problem related to btrfs that causes lock up and make the system unusable for a while. On a first try to fix I ran zypper dup (which is shorthand for zypper dist-upgrade) to upgrade all packages, just in case the problem magically disappears, but far from solve the problem the new kernel hung due the btrfs filesystem, again. And my system didn’t start anymore going to the recovery system. Looks to me that btrfs is still no well supported so I hightly recommend use ext4 instead.

WiFi-controlled camera slider

I have been helping one of my friends build a WiFi-controlled camera slider. He did all the mechanical design and I implemented the electronic and software parts. The camera slider is motorized using a single NEMA-17 stepper driven by the EasyDriver Stepper Motor Driver on top of an Arduino MKR1000.

Connection diagram

The electronics has been populated on a perforated prototype board.

The MKR1000 allows us to remotely control the movement of the camera slider by connecting to the MKR1000’s web interface. To access to the web interface, you’ll first need to connect to the slider’s ESSID and wait for a local IP address. Then you can connect to the control interface through http://192.168.1.1 and you will see something like this.

Slider Web interface

With the basic functionality working the next steps to be taken are:

  • Improve the mechanics to have less friction.
  • Improve the Control Web Interface style.

Links

Linux Kernel 4.17

Linus Torvalds has now released the official Linux 4.17, so it’s time for our traditional blog post summing up our contributions to the latest version of the Linux kernel. Collabora contributions were made by 9 different developers, at the same time we added our Reviewed-by tag to 60 patches, the Signed-off-by tag to 93 patches and the Tested-by tag to 4 patches.

This round, the DRM subsystem is the one that received more contributions from the Collaborans.  Read the original article here.