I have a beginner's problem. I have 2 nRF24L01+ devices. They are communicating with each other great, and I can talk with the nRF via SPI.
The problem is I want to display, on the serial monitor, the number of retransmitted packets (ARC_CNT) and the number of lost packets (PLOS_CNT), which are both in the "observe_tx" register on the nRF.
I am using the "Getting Started" example from RF24 1.3.1, with Arduino 1.84, with a few more bits added, and it all works great apart from getting it to show PLOS_CNT & ARC_CNT! I have tried:
printf_P(PSTR("OBSERVE_TX=%02x: PLOS_CNT=%x ARC_CNT=%x\r\n"));
But this does not give the correct result.
As you have probably guessed, I know nothing about C or C++. There must be a simple way of showing the 2 numbers?
The code I am using is:
#include <SPI.h>
#include "RF24.h"
#include <printf.h> // Required for "radio.printDetails();"
/****************** User Config ***************************/
/*** Set this radio as radio number 0 or 1 ***/
bool radioNumber = 0;
/* Hardware configuration: Set up nRF24L01 radio on SPI bus plus pins 7 & 8 */
RF24 radio(7, 8);
/**********************************************************/
byte addresses[][6] = {"1Node", "2Node"};
// Used to control whether this node is sending or receiving
bool role = 0;
void setup() {
//pinMode(53,OUTPUT); //may not be required after all
Serial.begin(115200);
printf_begin(); //required for "radio.printDetails();" to work
Serial.println(F("RF24/examples/GettingStarted"));
Serial.println(F("*** PRESS 'T' to begin transmitting to the other node"));
radio.begin();
// Set the PA Level low to prevent power supply related issues since this is a
// getting_started sketch, and the likelihood of close proximity of the devices. RF24_PA_MAX is default.
radio.setPALevel(RF24_PA_LOW); // _MIN, _LOW, _HIGH, _MAX
radio.setDataRate(RF24_250KBPS); //250KBPS, _1MBPS, _2MBPS Lowest rate gives longest range.
radio.setChannel(108); // 0 - 124 (2.4GHz - 2.524GHz) Usually above 100 best. USA 70 - 80 best.
radio.setRetries(15, 15); // set retry delay and no of retries. delay between retries, 0=250uS, 15 = 4000uS
radio.setCRCLength(RF24_CRC_16); // 8 or 16 bit crc
radio.printDetails();
Serial.print(radio.getChannel());
radio.setAutoAck(1);
// Open a writing and reading pipe on each radio, with opposite addresses
if (radioNumber) {
radio.openWritingPipe(addresses[1]);
radio.openReadingPipe(1, addresses[0]);
} else {
radio.openWritingPipe(addresses[0]);
radio.openReadingPipe(1, addresses[1]);
}
// Start the radio listening for data
radio.startListening();
}
void loop() {
/****************** Ping Out Role ***************************/
if (role == 1) {
radio.stopListening(); // First, stop listening so we can talk.
Serial.println(F("Now sending"));
unsigned long start_time = micros();
// Take the time, and send it. This will block until complete
if (!radio.write( &start_time, sizeof(unsigned long) )) {
Serial.println(F("failed"));
}
radio.startListening(); // Now, continue listening
unsigned long started_waiting_at = micros(); // Set up a timeout period, get the current microseconds
boolean timeout = false; // Set up a variable to indicate if a response was received or not
while (!radio.available()) {
// While nothing is received
if (micros() - started_waiting_at > 200000 ) {
// If waited longer than 200ms, indicate timeout and exit while loop
timeout = true;
break;
}
}
if (timeout) {
// Describe the results
Serial.println(F("Failed, response timed out."));
printf_P(PSTR("OBSERVE_TX=%02x: PLOS_CNT=%x ARC_CNT=%x\r\n"));
} else {
unsigned long got_time;
// Grab the response, compare, and send to debugging spew
radio.read( &got_time, sizeof(unsigned long) );
unsigned long end_time = micros();
// Spew it
Serial.print(F("Sent "));
Serial.print(start_time);
Serial.print(F(", Got response "));
Serial.print(got_time);
Serial.print(F(", Round-trip delay "));
Serial.print(end_time - start_time);
Serial.println(F(" microseconds"));
}
// Try again 1s later
delay(1000);
}
/****************** Pong Back Role ***************************/
if (role == 0) {
unsigned long got_time;
if (radio.available()) {
// Variable for the received timestamp
while (radio.available()) {
// While there is data ready
radio.read(&got_time, sizeof(unsigned long));
// Get the payload
}
radio.stopListening();
// First, stop listening so we can talk
radio.write(&got_time, sizeof(unsigned long));
// Send the final one back.
radio.startListening();
// Now, resume listening so we catch the next packets.
Serial.print(F("Sent response "));
Serial.println(got_time);
}
}
/****************** Change Roles via Serial Commands ***************************/
if (Serial.available()) {
char c = toupper(Serial.read());
if (c == 'T' && role == 0) {
Serial.println(F("*** CHANGING TO TRANSMIT ROLE -- PRESS 'R' TO SWITCH BACK"));
role = 1; // Become the primary transmitter (ping out)
} else if (c == 'R' && role == 1) {
Serial.println(F("*** CHANGING TO RECEIVE ROLE -- PRESS 'T' TO SWITCH BACK"));
role = 0; // Become the primary receiver (pong back)
radio.startListening();
}
}
} // Loop
