1KARPES_DAQ

Data acquisition software for the ultra low temperature ARPES system at the electronic structure research laboratory at Korea Advanced Institute of Science and Technology (KAIST).

User guide

Starting the software

1. Make sure that the HV rack switch is turned OFF.

2. Power on the DAQ PC (left) and log in with appropriate credentials.

3. Once the DAQ PC is on, power on the monitoring PC (right) and check if the network drive (D:) is connected.

4. On the monitoring PC, start the following programs from the desktop (order does not matter):

   • MG15
   • 🥶 Temperature controller
   • 😇 Motion controller
   • 🎛️ F70H (recommended to be always running): see here

   Check if each program is running correctly by looking at value updates.

5. Once the programs are running, double click on Start Servers in the desktop. In the window that appears, click the three Start Server buttons.

6. On the DAQ PC, start SES.exe from the desktop.

7. In SES, click on Calibration -> Voltages.... Close the voltage calibration window after making sure that the lens mode is angular and the pass energy is sufficiently low.

8. In SES, click on DA30 -> Control Theta... and close the control theta window that appears.

9. Double click on Start DAQ in the desktop. The system is now ready for data acquisition.

Stopping the software

Stopping the software is a reverse process of starting it. Close each program in the reverse order of starting them. Remember to not close the terminal window that appears when starting some programs; they will close automatically when the main window of the program is closed.

Conducting scans

Setting up scans

The DAQ software serves as a front-end for the SES software. All scans must be started with the Start button in the DAQ software, not SES. The user will not have to interact with SES menu items directly.

The slit indicator in the GUI determines the analyzer slit information recorded in the data file. Remember to set the slit indicator to the correct value when changing the analyzer slit.

All attributes are recorded when the scan ends.

Troubleshooting

Running scans without the DAQ software

SES grabs data attributes such as temperature and pressure from the user extension library UIExtension_Library.dll (source) program when a scan ends. The user extension library requests data from the DAQ software (Python) via a socket connection. If the DAQ program is not running, SES will not be able to grab the data attributes, and will hang indefinitely upon scan completion.

If this happens and for some reason the DAQ software cannot be started, the user can remove the user extension library with the following steps:

1. Click on Setup -> User Interfaces... in SES.
2. Select UIExtension_Library.dll in the list and click Delete.
3. Click Close to close the window.

Now, you can run scans from the SES software without the DAQ software running. Note that the data saved this way will not contain temperature, pressure, position, and other attributes that are grabbed from the DAQ software.

Starting the F70H Helium compressor program

The F70H program (🎛️) is used to monitor the helium compressor status and send notifications through slack. The program is started by double clicking on the desktop icon.

Upon starting the program, the user will be prompted to select a COM port. The Helium compressor is connected via a RS-232 serial connection to a USB-to-serial multiport adapter (4 ports), which is connected to a USB isolator and then to the monitoring PC. The COM port numbers are assigned by Windows and is subject to change, but the 4 ports of the multiport adapter are usually assigned to consecutive COM port numbers. In the list of available COM ports, look for 4 consecutive COM port numbers. The largest COM port number is the one assigned to the F70H, and the smallest COM port number is used for the RGA. The two middle ports are unused. If this is ambiguous, power on the RGA and check the COM port number assigned to it through the RGA software. Add 3 to this number to get the COM port number assigned to the F70H.

Once a valid COM port is selected, the program will start. Check the alarm status and make sure all indicators are showing 🟢.

Development

Prerequisites

• Python 3.11 or higher
• Additional dependencies for each program are listed in the pyproject.toml file in each subdirectory under src

Installation

1. Install uv

2. Clone the repository and navigate to the root directory.

3. Run:

   uv sync --all-extras --dev

4. Install pre-commit hooks by running pre-commit install in the root directory.

Notes

• Builds must be trigerred manually from the GitHub Actions page.
• When adding or modifying dependencies, use uv to manage them. Do not modify the pyproject.toml files manually.

Build status