Diff: main.cpp

Revision:

4:b2fc780be0b3

Parent:

3:5e25ec621190

Child:

5:a8b4e0857e8b

--- a/main.cpp	Fri Sep 06 19:55:25 2019 +0000
+++ b/main.cpp	Fri Sep 06 22:59:36 2019 +0000
@@ -27,25 +27,41 @@
 
 /******************** Setup radio transmitter ****************************/
 
+// Configure the User button as an interrupt
+InterruptIn button(USER_BUTTON, PullUp);
+
+// Initialize global variables
+uint8_t seq = 0;  //  Set initial transmit sequence to 0
 volatile bool txDone;
 CircularBuffer<uint8_t, BUF_SIZE> msg;
+MbedJSONValue message;
+Timer t;
 
+// Transmit Done Callback Handler
 void txDoneCB()
 {
     txDone = true;
+    printf("Tx Done.\r\n");
 }
 
+// Receive Done Callback Handler
 void rxDoneCB(uint8_t size, float rssi, float snr)
 {
+    printf("Rx Done.\r\n");
 }
 
-    // Define radio events for transmitter
+// Transmit Timeout Callback Handler
+void txTimeoutCB()
+{
+    printf("Tx Timeout.\r\n");
+}
 
+// Define radio events for transmitter
 const RadioEvents_t rev = {
     /* Dio0_top_half */     NULL,
     /* TxDone_topHalf */    NULL,
     /* TxDone_botHalf */    txDoneCB,
-    /* TxTimeout  */        NULL,
+    /* TxTimeout  */        txTimeoutCB,
     /* RxDone  */           rxDoneCB,
     /* RxTimeout  */        NULL,
     /* RxError  */          NULL,
@@ -53,6 +69,9 @@
     /* CadDone  */          NULL
 };
 
+/**
+* Function for printing the contents of the SX127x transmit buffer
+*/
 void print_radio_tx_buffer(uint8_t len)
 {
     printf("Tx Buffer = ");
@@ -63,6 +82,9 @@
     printf("\r\n\n");
 }
 
+/**
+* Function for adding bytes to the circular buffer for the message.
+*/
 void msg_append_bytes(uint8_t data[], uint8_t len)
 {
     for(int i=0; i < len; i++)
@@ -79,11 +101,20 @@
     }
 }
 
+/**
+* Function for adding a string to the circular buffer for the message
+*/
 void msg_append_string(string str, uint8_t len)
 {
     msg_append_bytes(reinterpret_cast<uint8_t*>(&str[0]), len);
 }    
 
+/**
+* Function for sending the message.
+*
+* @note This function copies the contents of the circular buffer to the transmit
+*       buffer.
+*/
 void msg_send()
 {
     uint8_t len = 0;
@@ -98,62 +129,92 @@
     print_radio_tx_buffer(len);
     txDone = false;
     Radio::Send(len, 0, 0, 0);   // begin transmission of payload 
+}
 
-    while (!txDone)
-    {
-        Radio::service();
-    }
-        
-    printf("Tx Done.\r\n");
+/**
+* Interrupt handler for the User button.
+*/
+void button_send()
+{
+   // Create an array to hold byte data
+    uint8_t data[] = {seq};
+    
+    // Append the byte array to the message
+    msg_append_bytes(data, sizeof(data)/sizeof(data[0]));
+    
+    // Append a new value to the message
+    data[0] = seq+1;
+    msg_append_bytes(data, sizeof(data)/sizeof(data[0]));
+    
+    // Append a string to the message
+    string myString = "Hello World!";
+    msg_append_string(myString, myString.length());
+    msg_send();
+
+    seq+=2;  // change payload (increment sequence number)
 }
 
+/**
+* Interrupt Handler for the User button.
+*/
+void button_send_json()
+{
+    string s;
+    seq++;
+    
+    //fill the object
+    message["btn_count"] = seq;
+    message["btn_timer"] = t.read();
+    message["my_str"] = "Hello World!";
+    message["my_boolean"] = false;
+    
+    //serialize it into a JSON string
+    s = message.serialize();
+    printf("json: %s\r\n", s.c_str());
+    
+    memcpy(Radio::radio.tx_buf, s.c_str(), s.length());
+    txDone = false;
+    Radio::Send(s.length(), 0, 0, 0);   // begin transmission of payload
+    t.reset();
+}
+
+/**
+* Function for initializing the SX127x radio.
+*/
 void radio_init()
 {
     // Start radio transmitter after POR or reset
-
     Radio::Init(&rev);
 
     //Set radio properties for transmitter
-
     Radio::Standby();
     Radio::LoRaModemConfig(BW_KHZ, SPREADING_FACTOR, 1);
     Radio::SetChannel(CF_HZ);
 
     // Set transmitter output power
-
     Radio::set_tx_dbm(TX_DBM);
 
     // Setup transmit packet payload  -> preambleLen, fixLen, crcOn, invIQ
-               
     Radio::LoRaPacketConfig(8, false, true, false);
 }
 
 int main()
 {        
     printf("\r\nreset-tx \n");
+//    button.fall(&button_send);
+    button.fall(&button_send_json);
     
     radio_init();
     
-    uint8_t seq = 0;  //  Set initial transmit sequence to 0
+    // Start a timer to track time between button presses
+    t.start();
 
-    for (;;) {
-        // Create an array to hold byte data
-        uint8_t data[] = {seq};
-        
-        // Append the byte array to the message
-        msg_append_bytes(data, sizeof(data)/sizeof(data[0]));
-        
-        // Append a new value to the message
-        data[0] = seq+1;
-        msg_append_bytes(data, sizeof(data)/sizeof(data[0]));
-        
-        // Append a string to the message
-        string myString = "Hello World!";
-        msg_append_string(myString, myString.length());
-        msg_send();
-
-        // Transmit payload every 500mS
-        wait(0.5);  // throttle sending rate 
-        seq+=2;  // change payload (increment sequence number)
+    for (;;)
+    {
+        // Transmit message on button press, service radio until tx complete.
+        while (!txDone)
+        {
+            Radio::service();
         }
+    }
 }