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How to fix the LIBUSB_ERROR_ACCESS error when launching OpenOCD from Visual Studio Code on Linux?

This error typically occurs due to missing or incorrect udev rules, which prevent user-space access to USB debug interfaces. Follow these steps to resolve the issue:

Open or create the udev rules file:

sudo nano /etc/udev/rules.d/60-openocd.rules

Add the appropriate rule based on your device’s lsusb output. For example:

SUBSYSTEM=="usb", ATTR{idVendor}=="<vendor_id>", ATTR{idProduct}=="<product_id>", MODE="0666", GROUP="plugdev"
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Reload the udev rules:

sudo udevadm control --reload-rules
sudo udevadm trigger
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Reconnect the EVK to apply the new rules.
Add your user to the appropriate group (typically plugdev or dialout):
sudo usermod -aG plugdev $USER
Log out and log back in, or reboot your system for the group changes to take effect.
Retry launching OpenOCD from Visual Studio Code.

How to fix issues when starting a new debug session?

If you experience problems when launching a new debug session, it may be due to stale or lingering openocd processes from previous sessions. To resolve this:

Check for any running openocd processes.
Terminate them using the following command:
pkill openocd
After terminating the stale processes, retry starting the debug session.

How to ensure reliable USB connectivity?

To ensure stable communication between EVK and your host computer:

Verify that the USB cable is firmly connected and not damaged.
Avoid using USB cables designed for charging only, because they may not support data transfer and can cause OpenOCD errors such as “No device found.”
Whenever possible, connect directly to the workstation’s USB ports instead of using USB hubs, which can introduce instability.

How to add a new project in Visual Studio Code QCC IDE?

In the QCC IDE view, open the QCC74x SDK folder as an existing project. In the Explorer pane, you’ll see example applications listed under the QCC IDE workspace dropdown. These applications are defined in the configuration file located at <SDK>/tools/qccide/qccIdeProjConfig.json.

In the Explorer pane, right‑click inside the folder where you want the new project directory. Select New > Folder. Enter a name for the folder (for example, new_project).
Open qccIdeProjConfig.json and add a new entry for your project. Use the format shown in template.jsont in the same directory as a reference.

Navigate to your new project folder and open the Makefile. Update the QCC74x_SDK_BASE variable so it points to the correct SDK base path on your system.