Simplified example to use less calls.

Defaults now to 32-byte payloads, but you can call in with any size under that.  Added example to docs.

examples/pingpair/pingpair.pde

@@ -29,13 +29,9 @@
 
 RF24 radio(8,9);
 
-// sets the address (and therefore the role of operation) of this unit.
-// lo = node0, hi = node1
-const int addr_pin = 7;
-
-// The actual value of the node's address will be filled in by the sketch
-// when it reads the addr_pin
-int node_address;
+// sets the role of this unit in hardware.  Connect to GND to be the 'ping' sender.
+// Connect to +5V to be the 'pong' receiver.
+const int role_pin = 7;
 
 //
 // Topology
@@ -47,21 +43,18 @@ const uint64_t pipes[2] = { 0xF0F0F0F0E1LL, 0xF0F0F0F0D2LL };
 //
 // Role management
 //
-// Set up address & role.  This sketch uses the same software for all the nodes
+// Set up role.  This sketch uses the same software for all the nodes
 // in this system.  Doing so greatly simplifies testing.  The hardware itself specifies
 // which node it is.
 //
-// This is done through the addr_pin.  Set it low for address #0, high for #1.
+// This is done through the role_pin
 //
 
 // The various roles supported by this sketch
-typedef enum { role_rx = 1, role_tx1, role_end } role_e;
+typedef enum { role_ping_out = 1, role_pong_back } role_e;
 
 // The debug-friendly names of those roles
-const char* role_friendly_name[] = { "invalid", "Receive", "Transmit"};
-
-// Which role is assumed by each of the possible hardware addresses
-const role_e role_map[2] = { role_rx, role_tx1 };
+const char* role_friendly_name[] = { "invalid", "Ping out", "Pong back"};
 
 // The role of the current running sketch
 role_e role;
@@ -69,17 +62,19 @@ role_e role;
 void setup(void)
 {
   //
-  // Address & Role
+  // Role
   //
   
-  // set up the address pin
-  pinMode(addr_pin, INPUT);
-  digitalWrite(addr_pin,HIGH);
-  delay(20); // Just to get a solid reading on the addr pin
+  // set up the role pin
+  pinMode(role_pin, INPUT);
+  digitalWrite(role_pin,HIGH);
+  delay(20); // Just to get a solid reading on the role pin
   
-  // read the address pin, establish our address and role
-  node_address = digitalRead(addr_pin) ? 0 : 1;
-  role = role_map[node_address];
+  // read the address pin, establish our role
+  if ( digitalRead(role_pin) )
+    role = role_pong_back;
+  else
+    role = role_ping_out;
 
   //
   // Print preamble
@@ -87,8 +82,7 @@ void setup(void)
   
   Serial.begin(9600);
   printf_begin();
-  printf("\n\rRF24 pingpair example\n\r");
-  printf("ADDRESS: %x\n\r",node_address);
+  printf("\n\rRF24/examples/pingpair/\n\r");
   printf("ROLE: %s\n\r",role_friendly_name[role]);
 
   //
@@ -97,32 +91,26 @@ void setup(void)
   
   radio.begin();
 
-  // Set channel (optional)
-  radio.setChannel(1);
-  
-  // Set size of payload (optional, but recommended)
-  // The library uses a fixed-size payload, so if you don't set one, it will pick
-  // one for you!
-  radio.setPayloadSize(sizeof(unsigned long));
-    
   //
-  // Open pipes to other nodes for communication (required)
+  // Open pipes to other nodes for communication
   //
   
   // This simple sketch opens two pipes for these two nodes to communicate
   // back and forth.
+  // Open 'our' pipe for writing
+  // Open the 'other' pipe for reading, in position #1 (we can have up to 5 pipes open for reading)
   
-  // We will open 'our' pipe for writing
-  radio.openWritingPipe(pipes[node_address]);
-  
-  // We open the 'other' pipe for reading, in position #1 (we can have up to 5 pipes open for reading)
-  int other_node_address;
-  if (node_address == 0)
-    other_node_address = 1;
+  if ( role == role_ping_out )
+  {
+    radio.openWritingPipe(pipes[0]);
+    radio.openReadingPipe(1,pipes[1]);
+  }
   else
-    other_node_address = 0;
-  radio.openReadingPipe(1,pipes[other_node_address]);
-  
+  {
+    radio.openWritingPipe(pipes[1]);
+    radio.openReadingPipe(1,pipes[0]);
+  }
+
   //
   // Start listening
   //
@@ -139,10 +127,10 @@ void setup(void)
 void loop(void)
 {
   //
-  // Transmitter role.  Repeatedly send the current time
+  // Ping out role.  Repeatedly send the current time
   //
   
-  if (role == role_tx1)
+  if (role == role_ping_out)
   {
     // First, stop listening so we can talk.
     radio.stopListening();
@@ -150,7 +138,7 @@ void loop(void)
     // Take the time, and send it.  This will block until complete
     unsigned long time = millis();
     printf("Now sending %lu...",time);
-    bool ok = radio.write( &time );  
+    bool ok = radio.write( &time, sizeof(unsigned long) );  
     
     // Now, continue listening
     radio.startListening();
@@ -171,7 +159,7 @@ void loop(void)
     {
       // Grab the response, compare, and send to debugging spew
       unsigned long got_time;
-      radio.read( &got_time );
+      radio.read( &got_time, sizeof(unsigned long) );
   
       // Spew it
       printf("Got response %lu, round-trip delay: %lu\n\r",got_time,millis()-got_time);
@@ -182,10 +170,10 @@ void loop(void)
   }
   
   //
-  // Receiver role.  Receive each packet, dump it out, and send it back to the transmitter
+  // Pong back role.  Receive each packet, dump it out, and send it back
   //
   
-  if ( role == role_rx )
+  if ( role == role_pong_back )
   {
     // if there is data ready
     if ( radio.available() )
@@ -196,7 +184,7 @@ void loop(void)
       while (!done)
       {
         // Fetch the payload, and see if this was the last one.
-        done = radio.read( &got_time );
+        done = radio.read( &got_time, sizeof(unsigned long) );
   
         // Spew it
         printf("Got payload %lu...",got_time);
@@ -206,7 +194,7 @@ void loop(void)
       radio.stopListening();
             
       // Send the final one back.
-      radio.write( &got_time );  
+      radio.write( &got_time, sizeof(unsigned long) );  
       printf("Sent response.\n\r");
       
       // Now, resume listening so we catch the next packets.
@@ -214,3 +202,4 @@ void loop(void)
     }
   }
 }
+// vim:ci sts=2 sw=2 ft=cpp