Add raw access to RX buffer.

src/CANController.cpp

@@ -167,6 +167,23 @@ int CANControllerClass::read()
   return _rxData[_rxIndex++];
 }
 
+size_t CANControllerClass::readBytes(char *buffer, size_t length) {
+  int bytesAvailable = available();
+  if (bytesAvailable <= 0) {
+    // No data left to consume.
+    return 0;
+  } 
+
+  if (bytesAvailable < length) {
+    // Limit to actually available data.
+    length = bytesAvailable;
+  }
+
+  memcpy(buffer, _rxData, length);
+  _rxIndex += length; // Consume the data.
+  return length;
+}
+
 int CANControllerClass::peek()
 {
   if (!available()) {

src/CANController.h

@@ -31,6 +31,10 @@ class CANControllerClass : public Stream {
   virtual int read();
   virtual int peek();
   virtual void flush();
+  virtual size_t readBytes(char *buffer, size_t length); // read chars from stream into buffer
+  virtual size_t readBytes(uint8_t *buffer, size_t length) {
+    return readBytes((char*)buffer, length);
+  }
 
   virtual void onReceive(void(*callback)(int));
 
@@ -44,6 +48,9 @@ class CANControllerClass : public Stream {
   virtual int sleep();
   virtual int wakeup();
 
+  /// Return the raw RX buffer for more efficient data access in high-performance scenarios.
+  uint8_t* getRxBuf() { return _rxData; }
+
 protected:
   CANControllerClass();
   virtual ~CANControllerClass();

src/ESP32SJA1000.h

@@ -26,6 +26,10 @@ class ESP32SJA1000Class : public CANControllerClass {
 
   virtual void onReceive(void(*callback)(int));
 
+  uint8_t getRmc() {
+    return readRegister(29);
+  }
+
   using CANControllerClass::filter;
   virtual int filter(int id, int mask);
   using CANControllerClass::filterExtended;