Configuring the virtual COM port

  1. Overview
  2. Determining the COM port number
  3. Setting the latency


If your device is connected over FTDI virtual COM port, you can achieve an improved update rate by minimizing the latency of the connection. This can only be done after installing CLS2Sim and connecting at least once to the device.

Determining the COM port number

Ensure that your device is connected to your PC over USB and start CLS2Sim. Open the connection settings and choose "Serial Port" as connection type. The "Serial port" drop-down list should now show the COM port of your device. Write down your COM port number and close CLS2Sim.

Setting the latency

Open the device manager in the Control Panel using an account with administrator rights. Open the section "Ports (COM & LPT)". Listed in that section you should find the entry "USB Serial Port (COM[X])", where [X] is the number of the COM port you determined before.

Right click the entry and select "Properties". The property window will open. In this window select the Tab "Port settings" and click on the button "Advanced...". If you see a message with the content "You must have write privileges in the registry for this device in order to modify the device's advanced settings.", that means you did not open the device manager as administrator. Close the properties and device manager windows and try again.

If you have adequate rights, the "Advanced Settings for COM[X]" window will open. Under "BM Options", set the "Latency Timer (msec)" to "1".

Click the "OK" button. The advanced settings window will close. In the properties window click the "OK" button again. Again the window will close. Now you can close the device manager. Unplug your device for at least 5 seconds and plug it in again. When connecting to your hardware with CLS2Sim you should now have a slightly improved hardware update rate.

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