diff --git a/cores/arduino/Arduino.h b/cores/arduino/Arduino.h
index 44e5a9a45..32ee32529 100644
--- a/cores/arduino/Arduino.h
+++ b/cores/arduino/Arduino.h
@@ -131,15 +131,23 @@ void noInterrupts(void);
 
 int digitalPinToInterrupt(pin_size_t pin);
 
+// These defines can be overridden by variant.h if implemented
 #define digitalPinToPort(x)    (x)
 #define digitalPinToBitMask(x) (x)
 #define portOutputRegister(x)  (x)
 #define portInputRegister(x)   (x)
 
+const struct device *digitalPinToPortDevice(pin_size_t pinNumber);
+int digitalPinToPinIndex(pin_size_t pinNumber);
+
 #if defined(CONFIG_PWM) || defined(CONFIG_DAC)
 void analogWriteResolution(int bits);
 #endif
 
+#if defined(__arm__)
+#define F_CPU (SystemCoreClock)
+#endif
+
 #include <variant.h>
 
 #if !defined(LED_BUILTIN) && defined(ZARD_LED_BUILTIN)
diff --git a/cores/arduino/zephyrCommon.cpp b/cores/arduino/zephyrCommon.cpp
index 894b6e8fc..8e8aa5052 100644
--- a/cores/arduino/zephyrCommon.cpp
+++ b/cores/arduino/zephyrCommon.cpp
@@ -218,6 +218,18 @@ void yield(void) {
 	k_yield();
 }
 
+const struct device *digitalPinToPortDevice(pin_size_t pinNumber) {
+	RETURN_ON_INVALID_PIN(pinNumber, nullptr);
+
+	return arduino_pins[pinNumber].port;
+}
+
+int digitalPinToPinIndex(pin_size_t pinNumber) {
+	RETURN_ON_INVALID_PIN(pinNumber, -1);
+
+	return arduino_pins[pinNumber].pin;
+}
+
 /*
  *  The ACTIVE_HIGH flag is set so that A low physical
  *  level on the pin will be interpreted as value 0.