Add MEDIUM_TURBO modem preset (#10988)

* Protobufs

* Wire up MEDIUM_TURBO modem preset

MEDIUM_TURBO (500 kHz, SF9, CR 4/5) already existed in the protobuf enum but
was never wired into firmware, so selecting it silently fell through to the
LONG_FAST default and rendered an "Invalid" display name.

Add its bw/sf/cr mapping (modemPresetToParams), display name (MediumTurbo/MedT),
PRESETS_STD membership (standard regions only — 500 kHz does not fit EU868's
250 kHz band, so it stays out of PRESETS_EU_868 and is rejected/clamped there),
and the MEDIUM SNR-grading bucket. Includes positive coverage in test_radio,
EU868-reject + US-accept coverage in test_admin_radio and test_mesh_beacon,
the STD preset count 9->10, an extended fuzz range, and the client-spec doc.

* Address review feedback on MEDIUM_TURBO tests

- test_mesh_beacon: assert has_mesh_beacon before checking the invalid preset was
  cleared, so the EU868-cleared test can't pass on a dropped message (matches the
  existing SHORT_TURBO test).
- test_fuzz_packets: draw modem presets from _ModemPreset_ARRAYSIZE instead of a
  hard-coded 17 so the fuzz range tracks future enum additions automatically.

.gitignore

@@ -1,5 +1,6 @@
 .pio
 pio
+.pio-docker
 pio.tar
 web
 web.tar

docs/lora_region_preset_compatibility_client_spec.md

@@ -69,7 +69,7 @@ message LoRaRegionPresetMap {
 ### 2.3 Why grouped (and the size envelope clients should respect)
 
 A `FromRadio` packet is capped at **512 bytes** (`MAX_TO_FROM_RADIO_SIZE`). Most regions
-share one identical preset list (the "standard" 9-preset list), so the map is delivered
+share one identical preset list (the "standard" 10-preset list), so the map is delivered
 **grouped**: `groups` holds each _distinct_ preset list once, and `region_groups` maps every
 known region to one of those groups by index. This keeps the encoded size additive
 (`groups` + `region_groups`) rather than multiplicative, well under the cap.
@@ -247,8 +247,8 @@ indices are assigned in region-table order (first region to use a profile create
 so they are stable as listed here:
 
 | group_index             | default_preset | licensed_only | presets                                                                                                                      |
-| ----------------------- | -------------- | ------------- | -------------------------------------------------------------------------------------------------------------- |
+| ----------------------- | -------------- | ------------- | ---------------------------------------------------------------------------------------------------------------------------- |
-| 0 (standard)            | `LONG_FAST`    | false         | LONG_FAST, LONG_SLOW, MEDIUM_SLOW, MEDIUM_FAST, SHORT_SLOW, SHORT_FAST, LONG_MODERATE, SHORT_TURBO, LONG_TURBO |
+| 0 (standard)            | `LONG_FAST`    | false         | LONG_FAST, LONG_SLOW, MEDIUM_SLOW, MEDIUM_FAST, SHORT_SLOW, SHORT_FAST, LONG_MODERATE, SHORT_TURBO, LONG_TURBO, MEDIUM_TURBO |
 | 1 (EU 868)              | `LONG_FAST`    | false         | LONG_FAST, LONG_SLOW, MEDIUM_SLOW, MEDIUM_FAST, SHORT_SLOW, SHORT_FAST, LONG_MODERATE                                        |
 | 2 (EU 866 SRD / "lite") | `LITE_FAST`    | false         | LITE_FAST, LITE_SLOW                                                                                                         |
 | 3 (EU 868 narrow)       | `NARROW_SLOW`  | false         | NARROW_FAST, NARROW_SLOW                                                                                                     |

src/DisplayFormatters.cpp

@@ -27,6 +27,9 @@ const char *DisplayFormatters::getModemPresetDisplayName(meshtastic_Config_LoRaC
     case PRESET(MEDIUM_FAST):
         return useShortName ? "MedF" : "MediumFast";
         break;
+    case PRESET(MEDIUM_TURBO):
+        return useShortName ? "MedT" : "MediumTurbo";
+        break;
     case PRESET(LONG_SLOW):
         return useShortName ? "LongS" : "LongSlow";
         break;

src/graphics/draw/UIRenderer.cpp

@@ -844,6 +844,7 @@ void UIRenderer::drawFavoriteNode(OLEDDisplay *display, OLEDDisplayUiState *stat
             return -6.0f;
         case PRESET(MEDIUM_SLOW):
         case PRESET(MEDIUM_FAST):
+        case PRESET(MEDIUM_TURBO):
             return -5.5f;
         case PRESET(SHORT_SLOW):
         case PRESET(SHORT_FAST):

src/mesh/MeshRadio.h

@@ -229,6 +229,11 @@ static inline void modemPresetToParams(meshtastic_Config_LoRaConfig_ModemPreset
         cr = 5;
         sf = 10;
         break;
+    case PRESET(MEDIUM_TURBO):
+        bwKHz = wideLora ? 1625.0f : 500.0f;
+        cr = 5;
+        sf = 9;
+        break;
     case PRESET(LONG_TURBO):
         bwKHz = wideLora ? 1625.0f : 500.0f;
         cr = 8;

src/mesh/RadioInterface.cpp

@@ -39,8 +39,8 @@
 #endif
 
 static const meshtastic_Config_LoRaConfig_ModemPreset PRESETS_STD[] = {
-    PRESET(LONG_FAST),  PRESET(LONG_SLOW),     PRESET(MEDIUM_SLOW), PRESET(MEDIUM_FAST), PRESET(SHORT_SLOW),
+    PRESET(LONG_FAST),     PRESET(LONG_SLOW),   PRESET(MEDIUM_SLOW), PRESET(MEDIUM_FAST),  PRESET(SHORT_SLOW), PRESET(SHORT_FAST),
-    PRESET(SHORT_FAST), PRESET(LONG_MODERATE), PRESET(SHORT_TURBO), PRESET(LONG_TURBO),  MODEM_PRESET_END};
+    PRESET(LONG_MODERATE), PRESET(SHORT_TURBO), PRESET(LONG_TURBO),  PRESET(MEDIUM_TURBO), MODEM_PRESET_END};
 
 static const meshtastic_Config_LoRaConfig_ModemPreset PRESETS_EU_868[] = {
     PRESET(LONG_FAST),  PRESET(LONG_SLOW),  PRESET(MEDIUM_SLOW),   PRESET(MEDIUM_FAST),

src/mesh/generated/meshtastic/config.pb.h

@@ -374,7 +374,11 @@ typedef enum _meshtastic_Config_LoRaConfig_ModemPreset {
  Note: TCXO with tight tolerances (±5 ppm or better) is *absolutely required* at these narrow bandwidths.
  Only compatible with SX127x and SX126x chipsets.
  Comparable link budget and data rate to LONG_MODERATE. */
-    meshtastic_Config_LoRaConfig_ModemPreset_TINY_SLOW = 15
+    meshtastic_Config_LoRaConfig_ModemPreset_TINY_SLOW = 15,
+    /* Medium Range - Turbo
+ This preset performs similarly to MEDIUM_FAST, but with 500kHz bandwidth.
+ It is not legal to use in all regions due to this wider bandwidth. */
+    meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_TURBO = 16
 } meshtastic_Config_LoRaConfig_ModemPreset;
 
 typedef enum _meshtastic_Config_LoRaConfig_FEM_LNA_Mode {
@@ -767,8 +771,8 @@ extern "C" {
 #define _meshtastic_Config_LoRaConfig_RegionCode_ARRAYSIZE ((meshtastic_Config_LoRaConfig_RegionCode)(meshtastic_Config_LoRaConfig_RegionCode_ITU2_125CM+1))
 
 #define _meshtastic_Config_LoRaConfig_ModemPreset_MIN meshtastic_Config_LoRaConfig_ModemPreset_LONG_FAST
-#define _meshtastic_Config_LoRaConfig_ModemPreset_MAX meshtastic_Config_LoRaConfig_ModemPreset_TINY_SLOW
+#define _meshtastic_Config_LoRaConfig_ModemPreset_MAX meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_TURBO
-#define _meshtastic_Config_LoRaConfig_ModemPreset_ARRAYSIZE ((meshtastic_Config_LoRaConfig_ModemPreset)(meshtastic_Config_LoRaConfig_ModemPreset_TINY_SLOW+1))
+#define _meshtastic_Config_LoRaConfig_ModemPreset_ARRAYSIZE ((meshtastic_Config_LoRaConfig_ModemPreset)(meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_TURBO+1))
 
 #define _meshtastic_Config_LoRaConfig_FEM_LNA_Mode_MIN meshtastic_Config_LoRaConfig_FEM_LNA_Mode_DISABLED
 #define _meshtastic_Config_LoRaConfig_FEM_LNA_Mode_MAX meshtastic_Config_LoRaConfig_FEM_LNA_Mode_NOT_PRESENT

src/modules/CannedMessageModule.cpp

@@ -2118,6 +2118,7 @@ static float getSnrLimit(meshtastic_Config_LoRaConfig_ModemPreset preset)
         return -6.0f;
     case PRESET(MEDIUM_SLOW):
     case PRESET(MEDIUM_FAST):
+    case PRESET(MEDIUM_TURBO):
         return -5.5f;
     case PRESET(SHORT_SLOW):
     case PRESET(SHORT_FAST):

test/test_admin_radio/test_main.cpp

@@ -484,7 +484,7 @@ static void test_validateConfigLora_allStdPresetsValidForUS()
         meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_SLOW,   meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_FAST,
         meshtastic_Config_LoRaConfig_ModemPreset_SHORT_SLOW,    meshtastic_Config_LoRaConfig_ModemPreset_SHORT_FAST,
         meshtastic_Config_LoRaConfig_ModemPreset_LONG_MODERATE, meshtastic_Config_LoRaConfig_ModemPreset_SHORT_TURBO,
-        meshtastic_Config_LoRaConfig_ModemPreset_LONG_TURBO,
+        meshtastic_Config_LoRaConfig_ModemPreset_LONG_TURBO,    meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_TURBO,
     };
 
     for (size_t i = 0; i < sizeof(stdPresets) / sizeof(stdPresets[0]); i++) {
@@ -498,7 +498,8 @@ static void test_validateConfigLora_allStdPresetsValidForUS()
 
 static void test_validateConfigLora_turboPresetsInvalidForEU868()
 {
-    // EU_868 has PRESETS_EU_868 which excludes SHORT_TURBO and LONG_TURBO
+    // EU_868 has PRESETS_EU_868 which excludes the 500 kHz turbo presets
+    // (SHORT_TURBO, LONG_TURBO, MEDIUM_TURBO)
     meshtastic_Config_LoRaConfig cfg = meshtastic_Config_LoRaConfig_init_zero;
     cfg.region = meshtastic_Config_LoRaConfig_RegionCode_EU_868;
     cfg.use_preset = true;
@@ -508,6 +509,9 @@ static void test_validateConfigLora_turboPresetsInvalidForEU868()
 
     cfg.modem_preset = meshtastic_Config_LoRaConfig_ModemPreset_LONG_TURBO;
     TEST_ASSERT_FALSE_MESSAGE(RadioInterface::validateConfigLora(cfg), "LONG_TURBO should be invalid for EU_868");
+
+    cfg.modem_preset = meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_TURBO;
+    TEST_ASSERT_FALSE_MESSAGE(RadioInterface::validateConfigLora(cfg), "MEDIUM_TURBO should be invalid for EU_868");
 }
 
 static void test_validateConfigLora_validPresetsForEU868()
@@ -598,13 +602,13 @@ static void test_validateConfigLora_unsetRegionOnlyAcceptsLongFast()
 
 static void test_validateConfigLora_allPresetsValidForLORA24()
 {
-    // LORA_24 uses PROFILE_STD (9 presets) with wideLora=true
+    // LORA_24 uses PROFILE_STD (10 presets) with wideLora=true
     meshtastic_Config_LoRaConfig_ModemPreset stdPresets[] = {
         meshtastic_Config_LoRaConfig_ModemPreset_LONG_FAST,     meshtastic_Config_LoRaConfig_ModemPreset_LONG_SLOW,
         meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_SLOW,   meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_FAST,
         meshtastic_Config_LoRaConfig_ModemPreset_SHORT_SLOW,    meshtastic_Config_LoRaConfig_ModemPreset_SHORT_FAST,
         meshtastic_Config_LoRaConfig_ModemPreset_LONG_MODERATE, meshtastic_Config_LoRaConfig_ModemPreset_SHORT_TURBO,
-        meshtastic_Config_LoRaConfig_ModemPreset_LONG_TURBO,
+        meshtastic_Config_LoRaConfig_ModemPreset_LONG_TURBO,    meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_TURBO,
     };
 
     for (size_t i = 0; i < sizeof(stdPresets) / sizeof(stdPresets[0]); i++) {
@@ -792,11 +796,11 @@ static void test_validateConfigLora_siblingLockedPresetStillFailsValidation()
 // RegionInfo preset list integrity tests
 // -----------------------------------------------------------------------
 
-static void test_presetsStd_hasNineEntries()
+static void test_presetsStd_hasTenEntries()
 {
-    // PROFILE_STD should have exactly 9 presets
+    // PROFILE_STD should have exactly 10 presets (adds MEDIUM_TURBO to the turbo cluster)
     const RegionInfo *us = getRegion(meshtastic_Config_LoRaConfig_RegionCode_US);
-    TEST_ASSERT_EQUAL(9, us->getNumPresets());
+    TEST_ASSERT_EQUAL(10, us->getNumPresets());
     TEST_ASSERT_EQUAL_PTR(PROFILE_STD.presets, us->getAvailablePresets());
 }
 
@@ -1320,7 +1324,7 @@ void setup()
     RUN_TEST(test_validateConfigLora_siblingLockedPresetStillFailsValidation);
 
     // RegionInfo preset list integrity
-    RUN_TEST(test_presetsStd_hasNineEntries);
+    RUN_TEST(test_presetsStd_hasTenEntries);
     RUN_TEST(test_presetsEU868_hasSevenEntries);
     RUN_TEST(test_presetsUndef_hasOneEntry);
     RUN_TEST(test_defaultPresetIsInAvailablePresets);

test/test_fuzz_packets/test_main.cpp

@@ -450,7 +450,8 @@ static meshtastic_AdminMessage fuzzAdminMessage()
         // manual bandwidth==0 path that used to SIGFPE the validator.
         r.set_config.which_payload_variant = meshtastic_Config_lora_tag;
         r.set_config.payload_variant.lora.region = (meshtastic_Config_LoRaConfig_RegionCode)rngRange(32);
-        r.set_config.payload_variant.lora.modem_preset = (meshtastic_Config_LoRaConfig_ModemPreset)rngRange(16);
+        r.set_config.payload_variant.lora.modem_preset =
+            (meshtastic_Config_LoRaConfig_ModemPreset)rngRange(_meshtastic_Config_LoRaConfig_ModemPreset_ARRAYSIZE);
         r.set_config.payload_variant.lora.use_preset = (rngRange(2) == 0);
         r.set_config.payload_variant.lora.bandwidth = rngRange(512); // includes 0
         r.set_config.payload_variant.lora.channel_num = rngNext();
@@ -553,7 +554,7 @@ static meshtastic_MeshBeacon fuzzBeacon()
         fuzzChannelSettings(b.offer_channel);
     b.offer_region = (meshtastic_Config_LoRaConfig_RegionCode)rngRange(32);
     b.has_offer_preset = (rngRange(2) == 0);
-    b.offer_preset = (meshtastic_Config_LoRaConfig_ModemPreset)rngRange(16);
+    b.offer_preset = (meshtastic_Config_LoRaConfig_ModemPreset)rngRange(_meshtastic_Config_LoRaConfig_ModemPreset_ARRAYSIZE);
     return b;
 }
 

test/test_mesh_beacon/test_main.cpp

@@ -251,6 +251,44 @@ static void test_adminValidation_turboPresetOnUS_isAccepted(void)
     TEST_ASSERT_EQUAL(meshtastic_Config_LoRaConfig_ModemPreset_SHORT_TURBO, moduleConfig.mesh_beacon.broadcast_on_preset);
 }
 
+/**
+ * Verify MEDIUM_TURBO is also cleared for EU_868. Like SHORT_TURBO/LONG_TURBO it is a 500 kHz preset
+ * that does not fit EU_868's 250 kHz band, so it must not survive admin validation there.
+ */
+static void test_adminValidation_mediumTurboPresetOnEU868_isCleared(void)
+{
+    resetConfig();
+
+    meshtastic_ModuleConfig_MeshBeaconConfig bcfg = meshtastic_ModuleConfig_MeshBeaconConfig_init_zero;
+    bcfg.has_broadcast_on_preset = true;
+    bcfg.broadcast_on_preset = meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_TURBO;
+
+    testAdmin->handleSetModuleConfig(makeBeaconModuleConfig(bcfg));
+
+    TEST_ASSERT_TRUE(moduleConfig.has_mesh_beacon);
+    TEST_ASSERT_FALSE(moduleConfig.mesh_beacon.has_broadcast_on_preset);
+}
+
+/**
+ * Verify MEDIUM_TURBO passes validation for US (PROFILE_STD allows the full turbo family).
+ * The same 500 kHz preset that is illegal in EU_868 must be preserved in permissive regions.
+ */
+static void test_adminValidation_mediumTurboPresetOnUS_isAccepted(void)
+{
+    resetConfig();
+    config.lora.region = meshtastic_Config_LoRaConfig_RegionCode_US;
+    initRegion();
+
+    meshtastic_ModuleConfig_MeshBeaconConfig bcfg = meshtastic_ModuleConfig_MeshBeaconConfig_init_zero;
+    bcfg.has_broadcast_on_preset = true;
+    bcfg.broadcast_on_preset = meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_TURBO;
+
+    testAdmin->handleSetModuleConfig(makeBeaconModuleConfig(bcfg));
+
+    TEST_ASSERT_TRUE(moduleConfig.mesh_beacon.has_broadcast_on_preset);
+    TEST_ASSERT_EQUAL(meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_TURBO, moduleConfig.mesh_beacon.broadcast_on_preset);
+}
+
 /**
  * Verify an out-of-range region code (255) is sanitised to UNSET rather than stored verbatim.
  * Important to prevent invalid proto enum values from reaching the broadcaster and being broadcast
@@ -1360,6 +1398,8 @@ BEACON_TEST_ENTRY void setup()
     RUN_TEST(test_adminValidation_turboPresetOnEU868_isCleared);
     RUN_TEST(test_adminValidation_longTurboPresetOnEU868_isCleared);
     RUN_TEST(test_adminValidation_turboPresetOnUS_isAccepted);
+    RUN_TEST(test_adminValidation_mediumTurboPresetOnEU868_isCleared);
+    RUN_TEST(test_adminValidation_mediumTurboPresetOnUS_isAccepted);
     RUN_TEST(test_adminValidation_unknownOfferRegion_isCleared);
     RUN_TEST(test_adminValidation_validOfferRegion_isPreserved);
     RUN_TEST(test_adminValidation_targetUnknownRegion_isCleared);

test/test_radio/test_main.cpp

@@ -195,6 +195,47 @@ static void test_applyModemConfig_customCodingRateLowerThanPreset()
     TEST_ASSERT_EQUAL_UINT8(8, testRadio->getCr());
 }
 
+// MEDIUM_TURBO performs like MEDIUM_FAST (sf=9, cr=5) but at 500 kHz. Verify the params resolve.
+static void test_applyModemConfig_mediumTurbo()
+{
+    config.lora = meshtastic_Config_LoRaConfig_init_zero;
+    config.lora.region = meshtastic_Config_LoRaConfig_RegionCode_US;
+    config.lora.use_preset = true;
+    config.lora.modem_preset = meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_TURBO;
+
+    testRadio->reconfigure();
+
+    TEST_ASSERT_EQUAL_UINT8(5, testRadio->getCr());
+    TEST_ASSERT_EQUAL_UINT8(9, testRadio->getSf());
+    TEST_ASSERT_FLOAT_WITHIN(0.01f, 500.0f, testRadio->getBw());
+}
+
+// MEDIUM_TURBO is a 500 kHz preset, so it is invalid for EU_868 and must clamp to the region default.
+static void test_clampConfigLora_mediumTurboInvalidForEU868()
+{
+    meshtastic_Config_LoRaConfig cfg = meshtastic_Config_LoRaConfig_init_zero;
+    cfg.use_preset = true;
+    cfg.region = meshtastic_Config_LoRaConfig_RegionCode_EU_868;
+    cfg.modem_preset = meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_TURBO;
+
+    RadioInterface::clampConfigLora(cfg);
+
+    TEST_ASSERT_EQUAL(meshtastic_Config_LoRaConfig_ModemPreset_LONG_FAST, cfg.modem_preset);
+}
+
+// MEDIUM_TURBO is valid for US (PROFILE_STD) and must be left unchanged.
+static void test_clampConfigLora_mediumTurboValidForUS()
+{
+    meshtastic_Config_LoRaConfig cfg = meshtastic_Config_LoRaConfig_init_zero;
+    cfg.use_preset = true;
+    cfg.region = meshtastic_Config_LoRaConfig_RegionCode_US;
+    cfg.modem_preset = meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_TURBO;
+
+    RadioInterface::clampConfigLora(cfg);
+
+    TEST_ASSERT_EQUAL(meshtastic_Config_LoRaConfig_ModemPreset_MEDIUM_TURBO, cfg.modem_preset);
+}
+
 // -----------------------------------------------------------------------
 // getRegionPresetMap() - region->valid-preset map sent to clients during want_config
 // -----------------------------------------------------------------------
@@ -317,6 +358,9 @@ void setup()
     RUN_TEST(test_applyModemConfig_codingRateMatchesPreset);
     RUN_TEST(test_applyModemConfig_customCodingRateHigherThanPreset);
     RUN_TEST(test_applyModemConfig_customCodingRateLowerThanPreset);
+    RUN_TEST(test_applyModemConfig_mediumTurbo);
+    RUN_TEST(test_clampConfigLora_mediumTurboInvalidForEU868);
+    RUN_TEST(test_clampConfigLora_mediumTurboValidForUS);
     RUN_TEST(test_regionPresetMap_coversAllRegionsWithinBounds);
     RUN_TEST(test_regionPresetMap_matchesRegionTable);
     exit(UNITY_END());