How to Use JLINK Script in VS Code: A Complete Guide

For MCU developers, VS Code is popular for its lightweight, cross‑platform nature, but many still switch to traditional IDEs (Keil, IAR) for compiling, flashing, and debugging. NXP’s MCUXpresso plugin for VS Code bridges this gap, yet custom actions often require JLINK Script, which is not part of the default JLINK logic.

Method 1 – Configure the .jlink Build Configurations file

Open the .jlink file located under the project’s Build Configurations directory. Set the “Script File” entry to the path of the script, e.g., flexspi_nor_release. Edit the corresponding JLink_hello_world.jlink file and add a line such as Report("JLINK Script TEST Mode 1 !!!");. Start a debug session; the message appears in the VS Code DEBUG CONSOLE , confirming the script was executed.

Method 2 – Place a .jlinkscript file alongside the .jlink file

Create a .jlinkscript file with the same base name as the .jlink file (e.g., JLink_hello_world.jlinkscript) in the same directory. Inside, add Report("JLINK Script TEST Mode 2 !!!");. When debugging, the same message is printed in the DEBUG CONSOLE , providing the same verification as Method 1.

Method 3 – Use the Flash Programmer’s Custom Script field

When flashing only, open the MCUXpresso plugin’s Flash Programmer and locate the CUSTOM SCRIPT option. Specify the path to a .jlinkscript file, then click Run . The script runs during flashing, but its output is not shown in the DEBUG CONSOLE ; instead, it appears in the Log view. Internally this method behaves like Method 1, as the plugin generates a temporary script.jlink file after clicking Preview .

Recommendation

If you need both debugging and script‑based initialization, use Method 1 or Method 2, as both provide console output for easy verification. If you only need to run a script during flashing, Method 3 is more direct, though it lacks immediate debug‑console feedback.

As the MCUXpresso VS Code plugin matures, developers can move away from traditional IDEs; JLINK Script’s flexibility enhances VS Code’s debugging capabilities, allowing fine‑grained control over hardware initialization and custom tasks, thereby improving overall development efficiency.