22 Aug 2021

[Howto] upgrade DEBIAN if distribution name has changed

by | posted in: computer | 0

problem: if the name of the DEBIAN distribution has changed (e.g. testing-version changes from “bullseye” to “bookworm”), aptitude denies the update procedure. It requests a manual command to proceed. solution: execute the command apt-get update –allow-releaseinfo-change (it updates the file … Continued

20 Oct 2020

[Facts] Raspberry Pi + I²C + MCP23017: digital output toggle timespan (Bash, Python, C)

by | posted in: computer, electronics | 0

purpose: measuring the timespan between rising/falling-edge (=off/on/off-change) of a digital-output-bank (GPA0…GPA7) testing equipment: -Raspberry Pi 3 Modell B-I2C-adress of MCP23017-chip = 0x20-MCP23017 register-adress of 8 digital-outputs: 0x14-Owon SDS7102 digital ocsilloscope conclusion: I²C-baudrate bash Python C 100.000 5,18 ms @ 75 … Continued

13 Oct 2020

[Howto] GTK+ and poppler (minimal example)

by | posted in: computer | 0

minimal working example, which creates a GTK-window and displays the first page of the given pdf-file.(compile with command: gcc example.c -o example `pkg-config –cflags –libs gtk+-3.0 poppler poppler-glib`) versions: GTK+ 3.24.23-2 and poppler-20.09.0-2

13 Oct 2020

[Howto] GTK+ and cairo (minimal example)

by | posted in: computer | 0

minimal working example, which creates a GTK-drawing-area and draws ‘Test.’ inside.(compile with command: gcc example.c -o example `pkg-config –cflags –libs gtk+-3.0`) versions: GTK+ 3.24.23-2 and cairo 1.16.0-4

18 Aug 2020

[FAQ] QElectroTech

by | posted in: computer, electronics | 0

Q: How to show power-contacts in contact-table?A: menu “project” –> menu-entry “project-properties” –> Tab “new folio” –> Tab “cross-references” –> type-entry “coil” –> enable “show the power contacts in the cross” Q: What is the difference between “label formula” and … Continued