fix(picker): preserve GPS-free RAK UART1 firmware

docs/_javascript/firmware_picker.js

@@ -614,9 +614,14 @@
       const sensorSuffix = (target.match(/-(?:full|reduced)$/) || [""])[0];
       const baseTarget = sensorSuffix ? target.slice(0, -sensorSuffix.length) : target;
       const rs232Replacement = mergedRs232Targets[baseTarget];
+      // Qualified RAK Full/Reduced images retain powered WisBlock GPS and
+      // reserve UART1 even when its bounded probe saw no receiver. The exact
+      // GPS-free Serial1 image remains a distinct, usable hardware choice.
+      const reservedRakUart1 = sensorSuffix &&
+        /^rak_4631_repeater_bridge_rs232_serial1(?:_lora_ota_no_external_sensors)?$/.test(baseTarget);
       // Preserve the exact sensor policy: a Full image does not replace a
       // missing Reduced image, or an older unsuffixed compatibility image.
-      const replacedRs232 = Boolean(rs232Replacement &&
+      const replacedRs232 = Boolean(!reservedRakUart1 && rs232Replacement &&
         [].concat(rs232Replacement).some(function (replacement) {
           return targets.has(replacement + sensorSuffix);
         }));
@@ -1677,7 +1682,9 @@
     if (info.rs232 && infrastructure) {
       const mode = chosen.mode;
       const uartNote = /^RAK_4631_repeater_unified_lora_ota-(?:full|reduced)$/i.test(profile.target) && profile.sensorProfile
-        ? "Use the UART and pin map for this exact board. Unified RAK4631 supports set bridge.uart 1 or set bridge.uart 2 while the bridge is stopped. UART1 pauses UART GPS while the bridge runs and restores it when stopped."
+        ? "Unified RAK4631 uses UART2 for the RS-232 bridge; select it with set bridge.uart 2 while the bridge is stopped. GPS safety guards reserve UART1 even when no GPS was detected. Use the separate GPS-free Serial1 image for UART1, with no powered UART GPS or header-connected W25 flash on those pins."
+        : /^RAK_4631_repeater_bridge_rs232_serial1(?:_lora_ota_no_external_sensors)?-(?:full|reduced)$/i.test(profile.target)
+          ? "This GPS-free Serial1 image uses UART1. Do not fit a powered UART GPS or header-connected W25 flash on the same UART1 pins. Use the unified UART2 image when those pins are occupied."
         : "Use the UART and pin map for this exact board. Canonical GPS-enabled RAK4631 uses UART2; select it with set bridge.uart 2 while the bridge is stopped. UART1 needs a compatible GPS-free image.";
       // MQTT images keep the historical bridge.enabled ESP-NOW alias.
       // Their independently saved UART uses the transport-specific controls.

docs/firmware_picker.md

@@ -28,8 +28,10 @@ or storage differences when a choice between different images is needed.
 RAK3401 and RAK4631 repeaters use one unified image per sensor policy for
 supported internal and external OTA storage. **Full** and **Reduced** choose
 optional sensor drivers; they do not select a storage module. The unified
-RAK4631 image also includes runtime RS-232 UART selection. Ethernet remains
-a separate RAK4631 hardware image. LoRa OTA still requires the matching
+RAK4631 image also includes RS-232 on UART2. A GPS-free Serial1 image remains
+separate because the unified image reserves UART1 for potentially powered
+GPS hardware. Header-connected W25 flash also occupies UART1 pins. Ethernet
+remains a separate RAK4631 hardware image. LoRa OTA still requires the matching
 OTAFIX bootloader and a package compatible with the installed target.
 
 The picker reads public release metadata from GitHub. It does not upload device

mkdocs.yml

@@ -127,7 +127,7 @@ extra_javascript:
   - _javascript/hosted_doc_links.js?v=20261007-1
   - _javascript/notification_builder.js?v=20261006-channel9
   - https://unpkg.com/leaflet@1.9.4/dist/leaflet.js
-  - _javascript/firmware_picker.js?v=20261008-rak-combined-1
+  - _javascript/firmware_picker.js?v=20261008-rak-combined-2
   - _javascript/telemetry_decoder.js?v=20261007-hosted-form
   - _javascript/management_decoder.js
   - _javascript/filter_tool.js?v=20261002-hashbytes-2plus

test/test_firmware_picker.js

@@ -1177,14 +1177,15 @@ const currentCatalog = picker.buildCatalog([
 assert.strictEqual(currentCatalog.rows.length, currentAssets.length);
 assert(currentCatalog.profiles.every(profile => profile.controls && profile.chipFamily !== 'unknown'));
 for (const [hardware, bases] of [
-  ['RAK_4631', ['RAK_4631_repeater_unified_lora_ota', 'RAK_4631_repeater_ethernet']],
+  ['RAK_4631', ['RAK_4631_repeater_unified_lora_ota', 'RAK_4631_repeater_ethernet',
+    'RAK_4631_repeater_bridge_rs232_serial1_lora_ota_no_external_sensors']],
   ['RAK_3401', ['RAK_3401_repeater_unified_lora_ota']],
 ]) {
   const context = {hardware, role: 'repeater'};
   const expected = bases.flatMap(base => ['full', 'reduced'].map(policy => base + '-' + policy));
   const visible = currentCatalog.profiles.filter(profile => picker.profileMatchesFacets(profile, context));
   assert.deepStrictEqual(visible.map(profile => profile.target).sort(), expected.sort(),
-    hardware + ' must recommend only combined storage/bridge images and genuine Ethernet variants');
+    hardware + ' must retain only combined storage/UART2 images, GPS-free UART1 and Ethernet variants');
   const choices = picker.firmwareProfileChoices(currentCatalog.profiles, context);
   assert.strictEqual(choices.length, expected.length, hardware + ' must have one choice per real image');
   assert.strictEqual(new Set(choices.map(choice => choice.label)).size, choices.length,
@@ -1195,12 +1196,19 @@ for (const [hardware, bases] of [
     if (hardware === 'RAK_4631') {
       const bridge = picker.runtimeDirections(profile, {mode: 'rs232'})
         .find(section => section.title.startsWith('RS232 bridge'));
-      assert(bridge && bridge.note.includes('set bridge.uart 1') && bridge.note.includes('pauses UART GPS'),
-        'Both combined sensor policies must explain runtime UART selection and GPS sharing');
-      assert(!bridge.note.includes('GPS-free image'));
+      assert(bridge && bridge.note.includes('set bridge.uart 2') && bridge.note.includes('reserve UART1'),
+        'Both combined sensor policies must explain the powered-GPS UART1 restriction');
+      assert(!bridge.note.includes('pauses UART GPS'));
     }
   }
 }
+for (const policy of ['full', 'reduced']) {
+  const serial1 = currentCatalog.profiles.find(profile => profile.target ===
+    'RAK_4631_repeater_bridge_rs232_serial1_lora_ota_no_external_sensors-' + policy);
+  assert(serial1 && serial1.controls.gps === false,
+    'The UART1 image must remain usable without the combined image\'s GPS reservation');
+  assert(!picker.runtimeDirections(serial1, {mode: 'rs232'}).some(section => section.title === 'GPS'));
+}
 const rakBridgeBase = 'RAK_4631_repeater_bridge_rs232_serial1_lora_ota_no_external_sensors';
 const rakPartialAssets = currentAssets.filter(file =>
   file.name.startsWith('RAK_4631_repeater_unified_lora_ota-full-') ||