feat(bmp): make SWO encoding (Manchester/UART) configurable

Refs: bmp enhancements; swo support #20
Marus · Jan 14, 2025 · 5c9a24d · 5c9a24d
1 parent 790df01
commit 5c9a24d
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Showing 4 changed files with 22 additions and 2 deletions.
diff --git a/debug_attributes.md b/debug_attributes.md
@@ -87,6 +87,7 @@ If the type is marked as `{...}` it means that it is a complex item can have mul
 | swoConfig<br>.decoders | {object} | Both | SWO Decoder Configuration |
 | swoConfig<br>.enabled | boolean | Both | Enable SWO decoding. |
 | swoConfig<br>.source | string | Both | Source for SWO data. Can either be "probe" to get directly from debug probe, or a serial port device to use a serial port external to the debug probe. |
+| swoConfig<br>.swoEncoding | string | Both | BMP only: SWO encoding data used at the line level. Depends on the probe hardware, native (the original one) supports only Manchester (self-clocked, but slower rates) while most other platforms (e.g. ST-LINK with BMP firmware) support only UART (frequency/baud rate has to match to within ~2%). |
 | swoConfig<br>.swoFrequency | number | Both | SWO frequency in Hz. |
 | swoConfig<br>.swoPath | string | Both | Path name when source is "file" or "serial", device name regex match when source is "probe" for BMP. Typically a /path-name or a serial-port-name |
 | swoConfig<br>.swoPort | string | Both | When server is "external" && source is "socket", port to connect to. Format [host:]port. For BMP, specifies the regex match of the USB interface contianing raw SWO data. |

diff --git a/package.json b/package.json
@@ -1524,6 +1524,15 @@
                                         "default": 0,
                                         "description": "SWO frequency in Hz; 0 will attempt to automatically calculate.",
                                         "type": "number"
+                                    },
+                                    "swoEncoding": {
+                                        "default": "uart",
+                                        "description": "BMP only: SWO encoding data used at the line level. Depends on the probe hardware, native (the original one) supports only Manchester (self-clocked, but slower rates) while most other platforms (e.g. ST-LINK with BMP firmware) support only UART (frequency/baud rate has to match to within ~2%).",
+                                        "type": "string",
+                                        "enum": [
+                                            "uart",
+                                            "manchester"
+                                        ]
                                     }
                                 },
                                 "required": [],
@@ -2683,6 +2692,15 @@
                                         "default": 0,
                                         "description": "SWO frequency in Hz.",
                                         "type": "number"
+                                    },
+                                    "swoEncoding": {
+                                        "default": "uart",
+                                        "description": "BMP only: SWO encoding data used at the line level. Depends on the probe hardware, native (the original one) supports only Manchester (self-clocked, but slower rates) while most other platforms (e.g. ST-LINK with BMP firmware) support only UART (frequency/baud rate has to match to within ~2%).",
+                                        "type": "string",
+                                        "enum": [
+                                            "uart",
+                                            "manchester"
+                                        ]
                                     }
                                 },
                                 "required": [],

diff --git a/src/bmp.ts b/src/bmp.ts
@@ -93,7 +93,7 @@ export class BMPServerController extends EventEmitter implements GDBServerContro
         const cpuFrequency = this.args.swoConfig.cpuFrequency;
 
         const ratio = Math.floor(cpuFrequency / swoFrequency) - 1;
-        const encoding = this.args.swoConfig.source === 'probe' ? 1 : 2;
+        const encoding = this.args.swoConfig.swoEncoding === 'manchester' ? 1 : 2;
 
         const commands: string[] = [];
 
@@ -112,7 +112,7 @@ export class BMPServerController extends EventEmitter implements GDBServerContro
         commands.push(this.args.swoConfig.profile ? 'EnablePCSample' : 'DisablePCSample');
 
         if (this.args.swoConfig.source === 'probe') {
-            commands.push('monitor traceswo');
+            commands.push(encoding === 2 ? `monitor traceswo ${swoFrequency}` : 'monitor traceswo');
         }
 
         return commands.map((c) => `interpreter-exec console "${c}"`);

diff --git a/src/common.ts b/src/common.ts
@@ -200,6 +200,7 @@ export interface SWOConfiguration {
     enabled: boolean;
     cpuFrequency: number;
     swoFrequency: number;
+    swoEncoding: 'manchester' | 'uart';
     decoders: any[];
     profile: boolean;
     source: string;