Add configurable DS18B20 temperature probe support

docs/API.md

@@ -538,3 +538,58 @@ Runtime behavior:
     AP always remains enabled.
     STA tries saved networks by priority.
     If STA disconnects, saved networks are retried every 30 seconds.
+
+---
+
+# Temperature Probe Setup API
+
+## Scan Temperature Sensors
+
+    POST /temps/scan
+
+Response:
+
+    {
+      "type": "temp_scan_response",
+      "ok": true,
+      "devices": [
+        {
+          "index": 1,
+          "address": "28:AA:BB:CC:DD:EE:FF:00"
+        }
+      ]
+    }
+
+## Assign Temperature Sensor
+
+    POST /temps/assign
+
+Request:
+
+    {
+      "id": "temp_1",
+      "index": 1
+    }
+
+Alternative request:
+
+    {
+      "slot": 1,
+      "index": 1
+    }
+
+## Clear Temperature Sensor
+
+    POST /temps/clear
+
+Request:
+
+    {
+      "id": "temp_1"
+    }
+
+Alternative request:
+
+    {
+      "slot": 1
+    }

docs/SERIAL_COMMANDS.md

@@ -414,3 +414,41 @@ Attempt STA WiFi connection using saved networks by priority.
 AP remains available at:
 
     192.168.4.1
+
+---
+
+# Temperature Probe Setup
+
+## scan temps
+
+Scans the DS18B20 1-Wire bus and prints detected sensor addresses.
+
+Example:
+
+    scan temps
+
+## assign temp <slot> <number>
+
+Assigns a detected physical sensor to a configured temp slot.
+
+Example:
+
+    assign temp 1 1
+    assign temp 2 2
+    save
+
+## clear temp <slot>
+
+Clears and disables a configured temp slot.
+
+Example:
+
+    clear temp 1
+
+Wiring reminder:
+
+    DS18B20 red    -> 3.3V
+    DS18B20 black  -> GND
+    DS18B20 yellow -> GPIO4
+
+A single 4.7k resistor is required between 3.3V and GPIO4/data.

docs/UART_PROTOCOL.md

@@ -232,3 +232,37 @@ Preferred response:
     {"type":"config_wifi","networks":[{"ssid":"Starlink","password":"password","priority":1},{"ssid":"Home WiFi","password":"password","priority":2}]}
 
 Lower priority numbers are tried first.
+
+---
+
+# Temperature Probe Setup
+
+## Scan Temperature Sensors
+
+Pico sends:
+
+    {"type":"scan_temps"}
+
+ESP32 responds:
+
+    {"type":"temp_scan_response","ok":true,"devices":[{"index":1,"address":"28:AA:BB:CC:DD:EE:FF:00"}]}
+
+## Assign Temperature Sensor
+
+Pico sends:
+
+    {"type":"assign_temp","id":"temp_1","index":1}
+
+Alternative:
+
+    {"type":"assign_temp","slot":1,"index":1}
+
+## Clear Temperature Sensor
+
+Pico sends:
+
+    {"type":"clear_temp","id":"temp_1"}
+
+Alternative:
+
+    {"type":"clear_temp","slot":1}

firmware/esp32/overland-controller/overland-controller.ino

@@ -474,9 +474,9 @@ void buildStatusDocument(JsonDocument& doc) {
         temp["id"] = appConfig.tempSensors[i].id;
         temp["name"] = appConfig.tempSensors[i].name;
         temp["enabled"] = appConfig.tempSensors[i].enabled;
-        temp["online"] = tempOnline[i];
-        if (tempOnline[i]) {
-            temp["temperature_f"] = tempValues[i];
+        temp["online"] = sensors.online[i];
+        if (sensors.online[i]) {
+            temp["temperature_f"] = sensors.tempsF[i];
         } else {
             temp["temperature_f"] = nullptr;
         }
@@ -912,6 +912,82 @@ void handleUartMessage(const String& line) {
         return;
     }
 
+    if (strcmp(type, "scan_temps") == 0) {
+        scanTempSensors();
+
+        DynamicJsonDocument response(2048);
+        response["type"] = "temp_scan_response";
+        response["ok"] = true;
+
+        JsonArray devices = response.createNestedArray("devices");
+
+        int count = getTempScanResultCount();
+        for (int i = 0; i < count; i++) {
+            JsonObject device = devices.createNestedObject();
+            device["index"] = i + 1;
+            device["address"] = getTempScanResultAddress(i);
+        }
+
+        serializeJson(response, DashboardSerial);
+        DashboardSerial.println();
+        return;
+    }
+
+    if (strcmp(type, "assign_temp") == 0) {
+        String id = doc["id"] | "";
+        int slot = doc["slot"] | 0;
+        int index = doc["index"] | 0;
+
+        int configIndex = -1;
+
+        if (id.length() > 0) {
+            configIndex = findTempConfigIndexForUart(id);
+        } else if (slot >= 1 && slot <= MAX_TEMP_SENSORS) {
+            configIndex = slot - 1;
+        }
+
+        if (configIndex < 0) {
+            sendError(DashboardSerial, "unknown_temp_sensor");
+            return;
+        }
+
+        if (!assignTempSensorByIndex(configIndex, index - 1)) {
+            sendError(DashboardSerial, "invalid_temp_selection");
+            return;
+        }
+
+        saveConfig();
+        sendConfigResponse(DashboardSerial);
+        return;
+    }
+
+    if (strcmp(type, "clear_temp") == 0) {
+        String id = doc["id"] | "";
+        int slot = doc["slot"] | 0;
+
+        int configIndex = -1;
+
+        if (id.length() > 0) {
+            configIndex = findTempConfigIndexForUart(id);
+        } else if (slot >= 1 && slot <= MAX_TEMP_SENSORS) {
+            configIndex = slot - 1;
+        }
+
+        if (configIndex < 0) {
+            sendError(DashboardSerial, "unknown_temp_sensor");
+            return;
+        }
+
+        if (!clearTempSensor(configIndex)) {
+            sendError(DashboardSerial, "unknown_temp_sensor");
+            return;
+        }
+
+        saveConfig();
+        sendConfigResponse(DashboardSerial);
+        return;
+    }
+
     if (strcmp(type, "save_config") == 0) {
         saveConfig();
         sendConfigResponse(DashboardSerial);
@@ -1191,6 +1267,47 @@ void handleDebugSerial() {
         }
     }
 
+    if (command == "scan temps") {
+        scanTempSensors();
+        printSensorAddresses();
+        return;
+    }
+
+    if (command.startsWith("assign temp ")) {
+        String rest = command.substring(12);
+        int space = rest.indexOf(' ');
+
+        if (space < 0) {
+            Serial.println("Invalid command. Use: assign temp <slot> <number>");
+            return;
+        }
+
+        int slot = rest.substring(0, space).toInt();
+        int index = rest.substring(space + 1).toInt();
+
+        if (!assignTempSensorByIndex(slot - 1, index - 1)) {
+            Serial.println("Invalid temp slot or sensor number.");
+            return;
+        }
+
+        saveConfig();
+        Serial.println("OK temp sensor assigned");
+        return;
+    }
+
+    if (command.startsWith("clear temp ")) {
+        int slot = command.substring(11).toInt();
+
+        if (!clearTempSensor(slot - 1)) {
+            Serial.println("Invalid temp slot.");
+            return;
+        }
+
+        saveConfig();
+        Serial.println("OK temp sensor cleared");
+        return;
+    }
+
     if (command.startsWith("tempname ")) {
         int firstSpace = command.indexOf(' ');
         int secondSpace = command.indexOf(' ', firstSpace + 1);
@@ -1524,6 +1641,102 @@ void handleWifiClear() {
     sendWifiConfigJson();
 }
 
+
+void sendTempScanJson() {
+    DynamicJsonDocument doc(2048);
+
+    doc["type"] = "temp_scan_response";
+    doc["ok"] = true;
+
+    JsonArray devices = doc.createNestedArray("devices");
+
+    int count = getTempScanResultCount();
+
+    for (int i = 0; i < count; i++) {
+        JsonObject device = devices.createNestedObject();
+        device["index"] = i + 1;
+        device["address"] = getTempScanResultAddress(i);
+    }
+
+    String output;
+    serializeJson(doc, output);
+    server.send(200, "application/json", output);
+}
+
+void handleTempScan() {
+    scanTempSensors();
+    sendTempScanJson();
+}
+
+void handleTempAssign() {
+    DynamicJsonDocument doc(512);
+    DeserializationError error = deserializeJson(doc, server.arg("plain"));
+
+    if (error) {
+        server.send(400, "application/json", "{\"ok\":false,\"error\":\"invalid_json\"}");
+        return;
+    }
+
+    String id = doc["id"] | "";
+    int slot = doc["slot"] | 0;
+    int index = doc["index"] | 0;
+
+    int configIndex = -1;
+
+    if (id.length() > 0) {
+        configIndex = findTempConfigIndexForUart(id);
+    } else if (slot >= 1 && slot <= MAX_TEMP_SENSORS) {
+        configIndex = slot - 1;
+    }
+
+    if (configIndex < 0) {
+        server.send(400, "application/json", "{\"ok\":false,\"error\":\"unknown_temp_sensor\"}");
+        return;
+    }
+
+    if (!assignTempSensorByIndex(configIndex, index - 1)) {
+        server.send(400, "application/json", "{\"ok\":false,\"error\":\"invalid_temp_selection\"}");
+        return;
+    }
+
+    saveConfig();
+    sendConfigJson();
+}
+
+void handleTempClear() {
+    DynamicJsonDocument doc(512);
+    DeserializationError error = deserializeJson(doc, server.arg("plain"));
+
+    if (error) {
+        server.send(400, "application/json", "{\"ok\":false,\"error\":\"invalid_json\"}");
+        return;
+    }
+
+    String id = doc["id"] | "";
+    int slot = doc["slot"] | 0;
+
+    int configIndex = -1;
+
+    if (id.length() > 0) {
+        configIndex = findTempConfigIndexForUart(id);
+    } else if (slot >= 1 && slot <= MAX_TEMP_SENSORS) {
+        configIndex = slot - 1;
+    }
+
+    if (configIndex < 0) {
+        server.send(400, "application/json", "{\"ok\":false,\"error\":\"unknown_temp_sensor\"}");
+        return;
+    }
+
+    if (!clearTempSensor(configIndex)) {
+        server.send(400, "application/json", "{\"ok\":false,\"error\":\"unknown_temp_sensor\"}");
+        return;
+    }
+
+    saveConfig();
+    sendConfigJson();
+}
+
 void handleSaveConfig() {
     saveConfig();
     sendConfigJson();

firmware/esp32/overland-controller/sensors.cpp

@@ -4,13 +4,15 @@
 
 #include "config.h"
 #include "sensors.h"
+#include "app_config.h"
 
 SensorData sensors;
 
 OneWire oneWire(ONEWIRE_PIN);
 DallasTemperature ds18b20(&oneWire);
 
-DeviceAddress sensorAddresses[4];
+DeviceAddress sensorAddresses[MAX_TEMP_SENSORS];
+String sensorAddressStrings[MAX_TEMP_SENSORS];
 int sensorCount = 0;
 
 float cToF(float c) {
@@ -21,67 +23,164 @@ bool validTempC(float tempC) {
     return tempC != DEVICE_DISCONNECTED_C && tempC > -55 && tempC < 125;
 }
 
-void printAddress(DeviceAddress address) {
+String addressToString(DeviceAddress address) {
+    String output = "";
+
     for (uint8_t i = 0; i < 8; i++) {
-        if (address[i] < 16) Serial.print("0");
-        Serial.print(address[i], HEX);
-        if (i < 7) Serial.print(":");
+        if (address[i] < 16) output += "0";
+        output += String(address[i], HEX);
+        if (i < 7) output += ":";
     }
+
+    output.toUpperCase();
+    return output;
+}
+
+void printAddress(DeviceAddress address) {
+    Serial.print(addressToString(address));
+}
+
+bool addressMatches(DeviceAddress address, const String& expected) {
+    if (expected.length() == 0) {
+        return false;
+    }
+
+    String actual = addressToString(address);
+    String normalizedExpected = expected;
+    normalizedExpected.toUpperCase();
+
+    return actual == normalizedExpected;
+}
+
+void clearSensorRuntimeData() {
+    for (int i = 0; i < MAX_TEMP_SENSORS; i++) {
+        sensors.tempsF[i] = -127.0;
+        sensors.online[i] = false;
+    }
+}
+
+int scanTempSensors() {
+    ds18b20.begin();
+
+    sensorCount = ds18b20.getDeviceCount();
+
+    if (sensorCount > MAX_TEMP_SENSORS) {
+        sensorCount = MAX_TEMP_SENSORS;
+    }
+
+    for (int i = 0; i < MAX_TEMP_SENSORS; i++) {
+        sensorAddressStrings[i] = "";
+    }
+
+    for (int i = 0; i < sensorCount; i++) {
+        if (ds18b20.getAddress(sensorAddresses[i], i)) {
+            sensorAddressStrings[i] = addressToString(sensorAddresses[i]);
+        }
+    }
+
+    return sensorCount;
+}
+
+int getTempScanResultCount() {
+    return sensorCount;
+}
+
+String getTempScanResultAddress(int index) {
+    if (index < 0 || index >= sensorCount) {
+        return "";
+    }
+
+    return sensorAddressStrings[index];
 }
 
 void printSensorAddresses() {
     Serial.println("DS18B20 Sensors Found:");
 
     for (int i = 0; i < sensorCount; i++) {
-        Serial.print("Sensor ");
-        Serial.print(i);
-        Serial.print(": ");
-        printAddress(sensorAddresses[i]);
-        Serial.println();
+        Serial.print(i + 1);
+        Serial.print(") ");
+        Serial.println(sensorAddressStrings[i]);
     }
 
     if (sensorCount == 0) {
         Serial.println("No DS18B20 sensors found.");
+    } else {
+        Serial.println("Use: assign temp <slot> <number>");
     }
 }
 
 void initSensors() {
-    ds18b20.begin();
-    sensorCount = ds18b20.getDeviceCount();
-
-    if (sensorCount > 4) {
-        sensorCount = 4;
-    }
-
-    for (int i = 0; i < sensorCount; i++) {
-        ds18b20.getAddress(sensorAddresses[i], i);
-    }
-
+    clearSensorRuntimeData();
+    scanTempSensors();
     printSensorAddresses();
 }
 
 void updateSensors() {
+    clearSensorRuntimeData();
+
     ds18b20.requestTemperatures();
 
-    float tempsF[4] = {-127, -127, -127, -127};
-    bool online[4] = {false, false, false, false};
+    for (int configIndex = 0; configIndex < MAX_TEMP_SENSORS; configIndex++) {
+        if (!appConfig.tempSensors[configIndex].enabled) {
+            continue;
+        }
 
-    for (int i = 0; i < sensorCount; i++) {
-        float tempC = ds18b20.getTempC(sensorAddresses[i]);
+        String configuredAddress = appConfig.tempSensors[configIndex].address;
+
+        if (configuredAddress.length() == 0) {
+            // Backward-compatible behavior:
+            // if no address is assigned, use physical scan order.
+            if (configIndex < sensorCount) {
+                float tempC = ds18b20.getTempC(sensorAddresses[configIndex]);
 
                 if (validTempC(tempC)) {
-            tempsF[i] = cToF(tempC);
-            online[i] = true;
+                    sensors.tempsF[configIndex] = cToF(tempC);
+                    sensors.online[configIndex] = true;
                 }
             }
 
-    sensors.temp1 = tempsF[0];
-    sensors.temp2 = tempsF[1];
-    sensors.temp3 = tempsF[2];
-    sensors.temp4 = tempsF[3];
-
-    sensors.temp1Online = online[0];
-    sensors.temp2Online = online[1];
-    sensors.temp3Online = online[2];
-    sensors.temp4Online = online[3];
+            continue;
+        }
+
+        for (int physicalIndex = 0; physicalIndex < sensorCount; physicalIndex++) {
+            if (!addressMatches(sensorAddresses[physicalIndex], configuredAddress)) {
+                continue;
+            }
+
+            float tempC = ds18b20.getTempC(sensorAddresses[physicalIndex]);
+
+            if (validTempC(tempC)) {
+                sensors.tempsF[configIndex] = cToF(tempC);
+                sensors.online[configIndex] = true;
+            }
+
+            break;
+        }
+    }
+}
+
+bool assignTempSensorByIndex(int configIndex, int scanIndex) {
+    if (configIndex < 0 || configIndex >= MAX_TEMP_SENSORS) {
+        return false;
+    }
+
+    if (scanIndex < 0 || scanIndex >= sensorCount) {
+        return false;
+    }
+
+    appConfig.tempSensors[configIndex].address = sensorAddressStrings[scanIndex];
+    appConfig.tempSensors[configIndex].enabled = true;
+
+    return true;
+}
+
+bool clearTempSensor(int configIndex) {
+    if (configIndex < 0 || configIndex >= MAX_TEMP_SENSORS) {
+        return false;
+    }
+
+    appConfig.tempSensors[configIndex].address = "";
+    appConfig.tempSensors[configIndex].enabled = false;
+
+    return true;
 }

firmware/esp32/overland-controller/sensors.h

@@ -1,19 +1,22 @@
 #pragma once
 
-struct SensorData {
-    float temp1 = -127.0;
-    float temp2 = -127.0;
-    float temp3 = -127.0;
-    float temp4 = -127.0;
+#include <Arduino.h>
+#include "app_config.h"
 
-    bool temp1Online = false;
-    bool temp2Online = false;
-    bool temp3Online = false;
-    bool temp4Online = false;
+struct SensorData {
+    float tempsF[MAX_TEMP_SENSORS];
+    bool online[MAX_TEMP_SENSORS];
 };
 
 extern SensorData sensors;
 
 void initSensors();
 void updateSensors();
+
+int scanTempSensors();
+int getTempScanResultCount();
+String getTempScanResultAddress(int index);
 void printSensorAddresses();
+
+bool assignTempSensorByIndex(int configIndex, int scanIndex);
+bool clearTempSensor(int configIndex);