diff --git a/index.html b/index.html
index 36e64fe..68b1506 100644
--- a/index.html
+++ b/index.html
@@ -99,9 +99,13 @@
         methods: {
             async askForSerialPort() {
                 this.connection = await SerialConnection.open();
+                this.connection.on("tx", (data) => console.log("tx", data));
+                this.connection.on("rx", (data) => console.log("rx", data));
             },
             async askForBleDevice() {
                 this.connection = await BleConnection.open();
+                this.connection.on("tx", (data) => console.log("tx", data));
+                this.connection.on("rx", (data) => console.log("rx", data));
             },
             async disconnect() {
                 if(this.connection){
diff --git a/src/connection/ble_connection.js b/src/connection/ble_connection.js
index 5eee2ac..c8beff1 100644
--- a/src/connection/ble_connection.js
+++ b/src/connection/ble_connection.js
@@ -88,8 +88,9 @@ class BleConnection extends Connection {
         }
     }
 
-    async sendToRadioFrame(data) {
-        await this.write(data);
+    async sendToRadioFrame(frame) {
+        this.emit("tx", frame);
+        await this.write(frame);
     }
 
 }
diff --git a/src/connection/connection.js b/src/connection/connection.js
index eb95f3c..f34977e 100644
--- a/src/connection/connection.js
+++ b/src/connection/connection.js
@@ -1,8 +1,9 @@
 import BufferWriter from "../buffer_writer.js";
 import BufferReader from "../buffer_reader.js";
 import Constants from "../constants.js";
+import EventEmitter from "../events.js";
 
-class Connection {
+class Connection extends EventEmitter {
 
     async close() {
         throw new Error("This method must be implemented by the subclass.");
@@ -130,7 +131,8 @@ class Connection {
 
     onFrameReceived(frame) {
 
-        // console.log("onFrameReceived", frame);
+        // emit received frame
+        this.emit("rx", frame);
 
         const bufferReader = new BufferReader(frame);
         const responseCode = bufferReader.readByte();
@@ -164,32 +166,32 @@ class Connection {
     }
 
     onAdvertPush(bufferReader) {
-        console.log("onAdvertPush", {
+        this.emit("AdvertPush", {
             publicKey: bufferReader.readBytes(32),
         });
     }
 
     onSendConfirmedPush(bufferReader) {
-        console.log("onSendConfirmedPush", {
+        this.emit("SendConfirmedPush", {
             ackCode: bufferReader.readBytes(4),
             roundTrip: bufferReader.readUInt32LE(),
         });
     }
 
     onMsgWaitingPush(bufferReader) {
-        console.log("onMsgWaitingPush", {
+        this.emit("MsgWaitingPush", {
 
         });
     }
 
     onContactsStartResponse(bufferReader) {
-        console.log("onContactsStartResponse", {
+        this.emit("ContactsStartResponse", {
             count: bufferReader.readUInt32LE(),
         });
     }
 
     onContactResponse(bufferReader) {
-        console.log("onContactResponse", {
+        this.emit("ContactResponse", {
             publicKey: bufferReader.readBytes(32),
             type: bufferReader.readByte(),
             flags: bufferReader.readByte(),
@@ -204,19 +206,19 @@ class Connection {
     }
 
     onEndOfContactsResponse(bufferReader) {
-        console.log("onEndOfContactsResponse", {
+        this.emit("EndOfContactsResponse", {
             mostRecentLastmod: bufferReader.readUInt32LE(),
         });
     }
 
     onSentResponse(bufferReader) {
-        console.log("onSentResponse", {
+        this.emit("SentResponse", {
 
         });
     }
 
     onSelfInfoResponse(bufferReader) {
-        console.log("onSelfInfoResponse", {
+        this.emit("SelfInfoResponse", {
             type: bufferReader.readByte(),
             txPower: bufferReader.readByte(),
             maxTxPower: bufferReader.readByte(),
@@ -233,19 +235,19 @@ class Connection {
     }
 
     onCurrTimeResponse(bufferReader) {
-        console.log("onCurrTimeResponse", {
+        this.emit("CurrTimeResponse", {
             epochSecs: bufferReader.readUInt32LE(),
         });
     }
 
     onNoMoreMessagesResponse(bufferReader) {
-        console.log("onNoMoreMessagesResponse", {
+        this.emit("NoMoreMessagesResponse", {
 
         });
     }
 
     onContactMsgRecvResponse(bufferReader) {
-        console.log("onContactMsgRecvResponse", {
+        this.emit("ContactMsgRecvResponse", {
             pubKeyPrefix: bufferReader.readBytes(6),
             pathLen: bufferReader.readByte(),
             txtType: bufferReader.readByte(),
diff --git a/src/connection/serial_connection.js b/src/connection/serial_connection.js
index ec69dab..4b40276 100644
--- a/src/connection/serial_connection.js
+++ b/src/connection/serial_connection.js
@@ -82,6 +82,7 @@ class SerialConnection extends Connection {
 
     async sendToRadioFrame(data) {
         // write "app to radio" frame 0x3c "<"
+        this.emit("tx", data);
         await this.writeFrame(0x3c, data);
     }
 
diff --git a/src/events.js b/src/events.js
new file mode 100644
index 0000000..1a8f238
--- /dev/null
+++ b/src/events.js
@@ -0,0 +1,42 @@
+class EventEmitter {
+
+    constructor() {
+        this.eventListenersMap = new Map();
+    }
+
+    on(event, callback) {
+
+        // create list of listeners for event if it doesn't exist
+        if(!this.eventListenersMap.has(event)){
+            this.eventListenersMap.set(event, []);
+        }
+
+        // add listener for event
+        this.eventListenersMap.get(event).push(callback);
+
+    }
+
+    off(event, callback) {
+
+        // remove callback from listeners for this event
+        if(this.eventListenersMap.has(event)){
+            const callbacks = this.eventListenersMap.get(event).filter(cb => cb !== callback);
+            this.eventListenersMap.set(event, callbacks);
+        }
+
+    }
+
+    emit(event, ...data) {
+
+        // invoke each listener for this event
+        if(this.eventListenersMap.has(event)){
+            for(const eventListener of this.eventListenersMap.get(event)){
+                setTimeout(() => eventListener(...data), 0);
+            }
+        }
+
+    }
+
+}
+
+export default EventEmitter;