diff --git a/sensor/platformio.ini b/sensor/platformio.ini
index bf58527..05cafd2 100644
--- a/sensor/platformio.ini
+++ b/sensor/platformio.ini
@@ -37,3 +37,14 @@ upload_flags =
 [env:d1_mini_lite]
 board = d1_mini_lite
 platform = espressif8266
+
+[env:t-rsc3] ; Lilygo T-RSC3
+platform = espressif32
+board = esp32-c3-devkitm-1
+lib_deps = 
+	${env.lib_deps}
+	https://github.com/adafruit/Adafruit_NeoPixel.git#1.11.1
+build_flags =
+ -D RSC3
+ -DARDUINO_USB_MODE=1
+ -DARDUINO_USB_CDC_ON_BOOT=1
diff --git a/sensor/src/constants.h b/sensor/src/constants.h
index 9ea0834..ddd8e60 100644
--- a/sensor/src/constants.h
+++ b/sensor/src/constants.h
@@ -25,3 +25,9 @@
 #else
 #define PUMP2_STATE_HIGH 1
 #endif 
+
+#define STATUS_BOOT 0
+#define STATUS_WIFI 2
+#define STATUS_OK 1
+#define STATUS_WAITING_DATA 3
+#define STATUS_WAITING_PANEL 4
\ No newline at end of file
diff --git a/sensor/src/sensor.ino b/sensor/src/sensor.ino
index 607c0b0..9a23df0 100644
--- a/sensor/src/sensor.ino
+++ b/sensor/src/sensor.ino
@@ -57,7 +57,18 @@ const int MINUTES_PER_DEGC = 45;
 #define DELAY_TIME_DEFAULT 40
 int delayTime = DELAY_TIME_DEFAULT;
 
-#ifdef ESP32
+
+#ifdef RSC3
+#define tub Serial1
+#define RX_PIN 3
+#define TX_PIN 10
+#define RTS_PIN 5  // RS485 direction control, RequestToSend TX or RX, required for MAX485 board.
+#define PIN_5_PIN 6
+
+#include <Adafruit_NeoPixel.h>
+Adafruit_NeoPixel pixels(1, 4, NEO_GRB + NEO_KHZ800);
+
+#elif ESP32
 #define tub Serial2
 #define RX_PIN 19
 #define TX_PIN 23
@@ -231,13 +242,42 @@ void onTargetTemperatureCommand(HANumeric temperature, HAHVAC* sender) {
     // the control unit reports that assume our commands worked
 }
 
+void setPixel(uint8_t color) {
+#ifdef RSC3
+    switch(color) {
+        case 0:
+            pixels.setPixelColor(0, pixels.Color(255,0,0));
+            break;
+        case 1:
+            pixels.setPixelColor(0, pixels.Color(0,255,0));
+            break;
+        case 2:
+            pixels.setPixelColor(0, pixels.Color(0,0,255));
+            break;
+        case 3:
+            pixels.setPixelColor(0, pixels.Color(255,255,0));
+            break;
+        case 4:
+            pixels.setPixelColor(0, pixels.Color(255,0,255));
+            break;
+    }     
+    pixels.show();
+#endif
+}
+
 boolean isConnected = false;
 void setup() {
     Serial.begin(115200);
     delay(1000);
 
+#ifdef RSC3
+    pixels.begin();
+    pixels.setBrightness(255);
+    setPixel(STATUS_BOOT);
+#else    
     pinMode(LED_BUILTIN, OUTPUT);
     digitalWrite(LED_BUILTIN, HIGH);
+#endif
 
     // Make sure you're in station mode
     WiFi.mode(WIFI_STA);
@@ -264,6 +304,7 @@ void setup() {
             Serial.print(".");
         }
     }
+    setPixel(STATUS_WIFI);
 
     if (WiFi.status() != WL_CONNECTED) {
 #ifdef AP_FALLBACK
@@ -416,7 +457,7 @@ String lastRaw5 = "";
 String lastRaw6 = "";
 String lastRaw7 = "";
 String lastJSON = "";
-int lastUptime = 0;
+uint32_t lastUptime = 0;
 String timeString = "";
 int msgLength = 0;
 boolean panelDetected = false;
@@ -426,6 +467,7 @@ void handleBytes(size_t len, uint8_t buf[]);
 void loop() {
     bool panelSelect = digitalRead(PIN_5_PIN);  // LOW when we are meant to read data
     if (tub.available() > 0) {
+        setPixel(STATUS_OK);
         size_t len = tub.available();
         //    Serial.printf("bytes avail = %u\n", len);
         uint8_t buf[len];  // TODO: swap to fixed buffer to help prevent fragmentation of memory
@@ -438,6 +480,14 @@ void loop() {
             msgLength = 0;
         }
     }
+    else {
+        if(panelDetected) {
+            setPixel(STATUS_WAITING_DATA);
+        }
+        else {
+            setPixel(STATUS_WAITING_PANEL);
+        }
+    }
 
     if (panelSelect == HIGH || !panelDetected) {  // Controller talking to other topside panels - we are in effect idle
 
@@ -454,7 +504,7 @@ void loop() {
 
         telnetLoop();
 
-        if (sendBuffer.isEmpty()) {  // Only handle status is we aren't trying to send commands, webserver and websocket
+        if (sendBuffer.isEmpty() || !panelDetected) {  // Only handle status is we aren't trying to send commands, webserver and websocket
                                      // can both block for a long time
 
             webserver.handleClient();
@@ -681,7 +731,7 @@ void handleMessage() {
                             float timeToTempValue = (tempDiff * MINUTES_PER_DEGC);
                             timeToTemp.setValue(timeToTempValue);
                         } else {
-                            timeToTemp.setValue(0);
+                            timeToTemp.setValue((float) 0);
                         }
                     }
                 } else if (result.substring(10, 12) == "2d") {  // "-"