Introducing DÆLOC – A Modern Data Acquisition Extension for LibreOffice Calc
DÆLOC (formerly LibreCalcDAQ) is a data acquisition extension for LibreOffice Calc, inspired by PLX-DAQ but with new features and modern capabilities. If you’ve used PLX-DAQ to log real-time data from your Arduino, DÆLOC is a powerful alternative with a familiar workflow and new capabilities.
What is DÆLOC?
DÆLOC is a LibreOffice Calc extension that allows real-time serial data logging directly into spreadsheets—perfect for Arduino projects, scientific experiments, and IoT applications.
It works just like PLX-DAQ but runs on LibreOffice, making it fully cross-platform (Windows, macOS, Linux).
Key Features
PLX-DAQ Compatibility – Supports most PLX-DAQ commands for easy migration. Real-Time Serial Data Logging – Stream live sensor readings from Arduino. Auto-scrolling support – Keep only the last N rows visible for live monitoring. MQTT Support (Pro Version) – Connect IoT devices wirelessly. Dynamic Charts (Pro Version) – Automatically visualize incoming data. Support for JSON (Pro Version) – Handle structured data.
DÆLOC Pro Now Available – Lifts Free Version Limits
Hello,
A quick update: DÆLOC Pro is now available for those who need unlimited data logging. This version removes the 250-row and 5-minute limits and supports all baud rates.
For the next 7 days, you can get 50% off with the code DAELOCROCKS (valid until).
I've now installed the free version to play (I'm not a frequent Calc user), it suites my current needs. At the moment that the limits become an issue I will more than likely buy.
But that is not holding me back working on this. I'm adding support for an alternative to the Excel data streamer functionality and a few other things...
Simply doesn’t work. Raspberry Pi 5 8Gb using Visual studio 1.105.1, PlatformIO and LibreOffice Calc 25.2.3.2 and DAELOC does absolutely nothing. PLX-DAQ on the Windows PC with Excel and the exact same code (also built with VSCode/ PlatformIO) works perfectly. USB connection to the target is detected but after that it’s blank boxes throughout.
In addition, there’s no option to Connect/Disconnect nor reset on connection.
Sorry to hear that DAELOC does not work with your setup. It should be possible to use DAELOC on an RPI5 as I use it on an RPI400.
First question, which version of DAELOC do you use? It should be 2.0.0
(Download from: https://daeloc.tektonica.com/)
On Raspberry Pi, if LibreOffice was installed via flatpak, it runs sandboxed and often can’t access serial ports in /dev by default. That makes DAELOC look like it does nothing even though the UI opens.
I’ve been through your suggestions and the results are as follows;
Flatpak is not installed and I don’t use it. Tried it once and the results were not positive. Ended up rebuilding the system!! LibreOffice was installed using “sudo apt etc” .
/dev/ttyUSB0 exists with crw-rw------+ permissions.
Groups returns around 20 results including my username as a group and sudo (I am a member of sudo).
Don’t have picocom but VSCode/PlatformIO terminal talks to the target with no problems.
One thing I have noticed is that the board is sending a spurious , non-printable character immediately after Serial.begin and before the CLEARSHEET command. Because there is no terminator after the character, it becomes the first character in the CLEARSHEET string so it is obviously corrupting the command. This appears to be an issue with ESP8266 and ESP32 boards.
Sending a standalone ‘\n’ immediately after Serial.begin separates the CLEARSHEET command from the character but the command and all subsequent commands still fail.
Curiously, I occasionally have had some messages pop up in the debug screen but the first few messages sent are missing then they stop again after four or five have been captured. Furthermore, the first few characters are missing from the first message that is captured. I cannot work out what causes this nor can I reproduce it reliably.
It’s all a bit flaky and, because it’s an embedded macro, I can’t even get into it to debug it and find out what’s going on.
Would you mind sharing a screenshot of what you see, or a copy of the serial output? I'm curious how it actually looks and also what serial output you get, as it can be a bug in the PLX-DAQ parsing on the side of DAELOC.
I think I have discovered the problem. As I said earlier, the ESP32 and ESP8266 modules I am using appear to throw out a stream of spurios characters after initialising the serial port. I’ve placed a blank line before the CLEARSHEET command to separate the giberish from the real output but that does not help. The only solution I have found is to start the target in Monitor mode to absorb the rubbish, disconnect the PlatformIO terminal then start up DAELOC. It then appears to work correctly.
It appears to me that DAELOC can’t cope with characters or strings outside of what it is expecting, particularly non-printables.
Now I have worked this out, it’s a bit of a pain but it is something I can live with in this application which is simply a cobbled together tool to debug some hardware. Not sure how acceptable it would be in a real world application.
This is a really useful tool, just needs a bit of work to improve it’s robustness and maybe some mechanism to report out-of-bounds input.
Thank you for the update. I'm glad you sorted it out for your application.
However, this is indeed an area I need to work on for DAELOC. Making it more robust to deal with unexpected data. Your input gives me something to work with.
Hi, I'm on Fedora 43 and calc 25.8.4.2, daeloc 2.0.0-1 free tier. Arduino 2560 mega over USB.
I'm running into an issue where the Daeloc interface stops responding every time I attempt to start recording data. Calc must be restarted as the Daeloc window won't close.
I have had Daeloc work in the past on this computer, so I wonder if something updated to break it. It freezes wether or not my Arduino is plugged in.
How did you install libreoffice? If you installed it with something like flatpak, then that can be the problem. If the permission are not set OK, you may not have access to serial ports.
Please run:
flatpak list | grep -i libreoffice
If you see LibreOffice there, try:
flatpak override --user org.libreoffice.LibreOffice --device=all
Restart LibreOffice and try again.
If you’re not using Flatpak, please paste:
ls -l /dev/ttyACM* /dev/ttyUSB*
permissions may block access
Also something to consider is uninstalling and installing DAELOC again.
It was installed through flatpak. It's the only choice through the OS's package manager. I ran both commands and it works now while the arduino is plugged in. The ACM and USB ports seem to stop existing when the arduino is not plugged in, so "ls -l /dev/ttyACM* /dev/ttyUSB*" fails to execute in that scenario.
DAELOC becomes unresponsive when trying to collect data from the wrong port.
Don’t forget you can log data straight into Excel spreadsheets and also grab data from web pages as well as the use/serial inputs . No cost MS addin required.
Comma delimited stuff can be sent straight to individual columns .
It works just like PLX-DAQ but runs on LibreOffice, making it fully cross-platform (Windows, macOS, Linux).
PLX-DAQ Compatibility – Supports most PLX-DAQ commands for easy migration.
Download & Install
Connect Your Arduino
Visit DÆLOC for more details and downloads.
I’d love to hear your feedback! Feel free to ask questions, request features, or share your Arduino projects using DÆLOC. 
