RTT works

.vscode/launch.json

@@ -0,0 +1,45 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "Cortex Debug",
+            "cwd": "${workspaceFolder}",
+            "executable": "./build/${workspaceFolderBasename}.elf",
+            "request": "launch",
+            "type": "cortex-debug",
+            "runToEntryPoint": "main",
+            "servertype": "jlink",
+            "device": "STM32F303RE",
+            "interface": "swd",
+            "runToMain": true,
+            "svdFile": "STM32F303xE.svd",
+            "rttConfig": {
+                "enabled": true,
+                "address": "auto",
+                "decoders": [
+                    {
+                        "label": "RTT",
+                        "port": 0,
+                        "type": "console",
+                        "timestamp": true
+                    }
+                ]
+            }
+            // "swoConfig": {
+            //     "enabled": false,
+            //     "cpuFrequency": 8000000,
+            //     "swoFrequency": 2000000,
+            //     "source": "probe",
+            //     "decoders": [{
+            //         "type": "console",
+            //         "label": "ITM",
+            //         "port": 0
+            //     }
+            //     ]
+            // }
+        }
+    ]
+}