...added getMotorRPM Function

DShotRMT.cpp

@@ -97,59 +97,76 @@ void DShotRMT::setThrottle(uint16_t throttle)
 // Receives and decodes a response frame from ESC containing eRPM info
 uint32_t DShotRMT::getERPM()
 {
-    static size_t rx_size = sizeof(_rx_symbols);
+    if (_isBidirectional)
-
-    if (_rmt_rx_channel == nullptr)
-        return _last_erpm;
-
-    // Attempt to receive a new frame
-    if (!rmt_receive(_rmt_rx_channel, _rx_symbols, rx_size, &_receive_config))
-        return _last_erpm;
-
-    uint16_t received_bits = 0;
-    _received_packet = 0;
-
-    // Decode raw RMT encoded bits
-    for (int i = 0; i < DSHOT_BITS_PER_FRAME; ++i)
     {
-        rmt_symbol_word_t symbols = _rx_symbols[i];
+        static size_t rx_size = sizeof(_rx_symbols);
 
-        // Validate signal polarity
+        if (_rmt_rx_channel == nullptr)
-        if (symbols.level0 != 1 || symbols.level1 != 0)
+            return _last_erpm;
-            break;
 
-        uint32_t total_ticks = symbols.duration0 + symbols.duration1;
+        // Attempt to receive a new frame
-        bool bit = (symbols.duration0 > (total_ticks / 2));
+        if (!rmt_receive(_rmt_rx_channel, _rx_symbols, rx_size, &_receive_config))
+            return _last_erpm;
 
-        _received_packet <<= 1;
+        uint16_t received_bits = 0;
-        _received_packet |= bit ? 1 : 0;
+        _received_packet = 0;
 
-        received_bits++;
+        // Decode raw RMT encoded bits
+        for (int i = 0; i < DSHOT_BITS_PER_FRAME; ++i)
+        {
+            rmt_symbol_word_t symbols = _rx_symbols[i];
+
+            // Validate signal polarity
+            if (symbols.level0 != 1 || symbols.level1 != 0)
+                break;
+
+            uint32_t total_ticks = symbols.duration0 + symbols.duration1;
+            bool bit = (symbols.duration0 > (total_ticks / 2));
+
+            _received_packet <<= 1;
+            _received_packet |= bit ? 1 : 0;
+
+            received_bits++;
+        }
+
+        if (received_bits < 16)
+            return _last_erpm;
+
+        // Extract data & checksum from packet
+        uint16_t packet_data = _received_packet >> 4;
+        uint8_t recalc_packet_crc = (packet_data ^ (packet_data >> 4) ^ (packet_data >> 8)) & 0x0F;
+        uint8_t packet_crc = _received_packet & 0x0F;
+
+        if (recalc_packet_crc != packet_crc)
+            return _last_erpm;
+
+        // Assume received value is DShot eRPM
+        uint16_t throttle = packet_data >> 1;
+
+        // Filter noise values
+        if (throttle < DSHOT_THROTTLE_MIN || throttle > DSHOT_THROTTLE_MAX)
+            return _last_erpm;
+
+        // Approximate eRPM (ESC dependent, scale factor can be tuned)
+        _last_erpm = throttle * 100;
+        return _last_erpm;
     }
-
+    // Nothing to do here
-    if (received_bits < 16)
-        return _last_erpm;
-
-    // Extract data & checksum from packet
-    uint16_t packet_data = _received_packet >> 4;
-    uint8_t recalc_packet_crc = (packet_data ^ (packet_data >> 4) ^ (packet_data >> 8)) & 0x0F;
-    uint8_t packet_crc = _received_packet & 0x0F;
-
-    if (recalc_packet_crc != packet_crc)
-        return _last_erpm;
-
-    // Assume received value is DShot eRPM
-    uint16_t throttle = packet_data >> 1;
-
-    // Filter noise values
-    if (throttle < DSHOT_THROTTLE_MIN || throttle > DSHOT_THROTTLE_MAX)
-        return _last_erpm;
-
-    // Approximate eRPM (ESC dependent, scale factor can be tuned)
-    _last_erpm = throttle * 100;
     return _last_erpm;
 }
 
+// Translate eRPM value to RPM taking magnet count as parameter
+uint32_t DShotRMT::getMotorRPM(uint8_t magnet_count)
+{
+    uint8_t pole_count = magnet_count / 2;
+
+    if (pole_count == 0)
+        pole_count = 1;
+
+    uint32_t rpm = getERPM() / pole_count;
+    return rpm;
+}
+
 // --- Encode DShot TX Frame ---
 // Converts a 16-bit packet into a valid DShot Frame for RMT
 void DShotRMT::encodeDShotTX(uint16_t dshot_packet, rmt_symbol_word_t *symbols, size_t &count)

DShotRMT.h

@@ -55,19 +55,17 @@ public:
     // Initializes the RMT TX and RX channels
     void begin();
 
-    // Sets a new throttle value (0-2047) and sends it repeatedly
+    // Sets a new throttle value (48-2047) and sends it repeatedly
     void setThrottle(uint16_t throttle);
 
-    // Receives and decodes the latest eRPM value from ESC, if available
+    // Receives and decodes the latest value from ESC, if available
     uint32_t getERPM();
+    uint32_t getMotorRPM(uint8_t magnet_count);
 
     // Accessors for GPIO and DShot mode
     gpio_num_t getGPIO() const { return _gpio; }
     dshot_mode_t getDShotMode() const { return _mode; }
 
-    // Stores the last valid eRPM received from the ESC
-    uint32_t _last_erpm = 0;
-
 private:
     // Converts a 16-bit DShot packet into RMT symbols and appends pause
     void encodeDShotTX(uint16_t dshot_packet, rmt_symbol_word_t *symbols, size_t &count);
@@ -96,4 +94,7 @@ private:
     // --- RMT Symbol Buffer ---
     rmt_symbol_word_t _rx_symbols[RX_BUFFER_SIZE] = {};
     rmt_symbol_word_t _tx_symbols[TX_BUFFER_SIZE] = {};
+
+    // Stores the last valid eRPM received from the ESC
+    uint32_t _last_erpm = 0;
 };

examples/dshot300/dshot300.ino

@@ -20,6 +20,9 @@ constexpr auto DSHOT_MODE = DSHOT300;
 // BiDirectional DShot Support (default: false)
 constexpr auto IS_BIDIRECTIONAL = true;
 
+// Motor Magnet count for RPM calculation
+constexpr auto MOTOR01_MAGNET_COUNT = 14;
+
 // Setup Motor Pin, DShot Mode and optional BiDirectional Support
 DShotRMT motor01(MOTOR01_PIN, DSHOT_MODE, IS_BIDIRECTIONAL);
 
@@ -37,7 +40,7 @@ void setup()
   //
   USB_Serial.println("**********************");
   USB_Serial.println("DShotRMT Demo started.");
-  USB_Serial.println("Enter a throttle value (48 – 2047):");
+  USB_Serial.println("Enter a throttle value (48–2047):");
 }
 
 void loop()
@@ -58,12 +61,12 @@ void loop()
     {
       last_print_time = now;
 
-      uint32_t erpm = motor01.getERPM();
+      uint32_t rpm = motor01.getMotorRPM(MOTOR01_MAGNET_COUNT);
 
-      USB_Serial.print("Sent Throttle: ");
+      USB_Serial.print("Throttle: ");
       USB_Serial.print(throttle_input);
-      USB_Serial.print(" | eRPM: ");
+      USB_Serial.print(" | RPM: ");
-      USB_Serial.println(erpm);
+      USB_Serial.println(rpm);
     }
   }
 }
@@ -86,7 +89,7 @@ int readSerialThrottle()
     USB_Serial.print("Throttle set to: ");
     USB_Serial.println(last_throttle);
     USB_Serial.println("***********************************");
-    USB_Serial.println("Enter a throttle value (48 – 2047):");
+    USB_Serial.println("Enter a throttle value (48–2047):");
   }
 
   return last_throttle;