Lämmämõõdusk

Description

A device that measures the ambient temperature in the environment in which it is located. And displays it on the screen.

Artistic description

Plant-like structures. Display like blossom. Bottom woodblock aged with brushing with a wire brush and oxidation solution (steel wool + vingar).

Animations

When the number to display changes it plays short animation.

Technical description

The first goal was to test an easier way to connect 7-segs and shift registers.
Main CPU, Arduino pro mini, uses thermistor to calculate temperature. Uses two different algorithms for this: Steinhart-hart equation and Beta model equation.
The display consists of two seven-segment displays. Drived by two 74HC595 shift registers. Which is connected to the seven-segment displays in a non-traditional way.This makes the construction easier.

Parts list

noDescriptionpcs
1Arduino pro mini Mega328p 5V1
2Shift Register SN74HC595N2
37-segment 5611BH / 5161BS2
4Resistor 12016
5CH340E USB to TTL BTE17-061
6Thermistor 10k1
7Resistor 10K1

Readin data

The simplest way to read serial data is to use Miniterm:

Also, I have made two Python scripts. read.py and simple GUI app gui.py. What display average temperature.

Links

Using AI to colourize black and white drawings

I found this deep learning project. It is meant and trained to colourize old black and white photos. And it does a very good job. But what it does when I use black and white drawings?

If the picture depicts a person it works pretty well. Although it loves yellowish red tones. But with other things, the results are not so good.

The left is original and the right is colourized by AI.

Link to Colab notebook:

Tutorial how to use Google Colab:

An easy way:

Linux special permission bits

Image: https://pamirwebhost.com/check-linux-file-permissions-with-ls/

SetUID

We can enable files to be run by the permission of the owner of the file. Like when we change password (command passwd). When you run the password command, its being run as root.

$ ls -l /usr/bin/passwd
-rwsr-xr-x 1 root root 68208 May 28 09:37 /usr/bin/passwd

The s stands for SetUID. When the s is substituted where irregular bit would be, it allows us to run the file with the permissions of the owner of the file.

To enable the SetUID bit:

$ sudo chmod u+s file.txt
or
$ sudo chmod 4755 file.txt
$ ls -l test.txt
-rwSrw-r-- 1 taunoerik taunoerik 2952 Sep  1 17:36 test.txt

Passwords are stored on /etc/shadow file.

$ ls -l /etc/shadow
-rw-r----- 1 root shadow 1377 Jul 29 09:15 /etc/shadow

SetGID

You can run a file using group permissions with setgid or set group ID. This allows you to run a file as a member of the file group.

To enable SetGID bit:

$ sudo chmod g+s file.txt
or
$ sudo chmod 2755 file.txt

Sticky Bit

This bit sticks a file or folder down. It makes it so anyone can write to a file or folder, but they can’t actually delete anything. Only the owner of root can delete anything.

Temporary files are stored /tmp. There’s a special permission but at the end here t, this means everyone can add and modify files in the slash tmp directory, but only root or the owner can delete the slash tmp directory.

To enable Sticky Bit:

$ sudo chmod +t test/
or
$ sudo chmod 1755 test/

Getting to the hill

It reminds me of a Medieval Norman castle. They call it Motte. It is a giant mound of earth with a keep, or tower, built on top.

There’s the letter A. Alpha – the beginning.

Ladder to heaven.

This golden flowers looks like a flower family Apiaceae or Umbelliferae or how it would be right to say about them … Some of them are edible (like a Parsley and carrot) but some are toxic (like a giant hogweed).