diff --git a/RFM69.cpp b/RFM69.cpp
index aac4530..b3bc30d 100644
--- a/RFM69.cpp
+++ b/RFM69.cpp
@@ -37,8 +37,10 @@ uint8_t RFM69::ACK_REQUESTED;
 uint8_t RFM69::ACK_RECEIVED; // should be polled immediately after sending a packet with ACK request
 int16_t RFM69::RSSI;          // most accurate RSSI during reception (closest to the reception)
 volatile bool RFM69::_haveData;
+RFM69 *RFM69::_instance = nullptr;
 
 RFM69::RFM69(uint8_t slaveSelectPin, uint8_t interruptPin, bool isRFM69HW_HCW, SPIClass *spi) {
+  _instance = this;
   _slaveSelectPin = slaveSelectPin;
   _interruptPin = interruptPin;
   _mode = RF69_MODE_STANDBY;
@@ -227,6 +229,12 @@ void RFM69::setNetwork(uint8_t networkID)
   writeReg(REG_SYNCVALUE2, networkID);
 }
 
+//set user's ISR callback
+void RFM69::setIsrCallback(void (*callback)())
+{
+  _isrCallback = callback;
+}
+
 // Control transmitter output power (this is NOT a dBm value!)
 // the power configurations are explained in the SX1231H datasheet (Table 10 on p21; RegPaLevel p66): http://www.semtech.com/images/datasheet/sx1231h.pdf
 // valid powerLevel parameter values are 0-31 and result in a directly proportional effect on the output/transmission power
@@ -446,7 +454,11 @@ void RFM69::interruptHandler() {
 }
 
 // internal function
-ISR_PREFIX void RFM69::isr0() { _haveData = true; }
+ISR_PREFIX void RFM69::isr0() {
+  _haveData = true;
+  if (_instance->_isrCallback)
+    _instance->_isrCallback();
+}
 
 // internal function
 void RFM69::receiveBegin() {
diff --git a/RFM69.h b/RFM69.h
index 491fa7e..c5f029c 100644
--- a/RFM69.h
+++ b/RFM69.h
@@ -203,6 +203,7 @@ class RFM69 {
     bool initialize(uint8_t freqBand, uint16_t ID, uint8_t networkID=1);
     void setAddress(uint16_t addr);
     void setNetwork(uint8_t networkID);
+    void setIsrCallback(void (*callback)());
     virtual bool canSend();
     virtual void send(uint16_t toAddress, const void* buffer, uint8_t bufferSize, bool requestACK=false);
     virtual bool sendWithRetry(uint16_t toAddress, const void* buffer, uint8_t bufferSize, uint8_t retries=2, uint8_t retryWaitTime=RFM69_ACK_TIMEOUT);
@@ -247,6 +248,7 @@ class RFM69 {
     void interruptHandler();
     virtual void interruptHook(uint8_t CTLbyte __attribute__((unused))) {};
     static volatile bool _haveData;
+    static RFM69 *_instance;
     virtual void sendFrame(uint16_t toAddress, const void* buffer, uint8_t size, bool requestACK=false, bool sendACK=false);
 
     // for ListenMode sleep/timer
@@ -260,6 +262,7 @@ class RFM69 {
     uint8_t _powerLevel;
     bool _isRFM69HW;
     SPIClass *_spi;
+    void (*_isrCallback)() = nullptr;
 #if defined (SPCR) && defined (SPSR)
     uint8_t _SPCR;
     uint8_t _SPSR;