Test code that provides a shell to integrate a NRF24 transceiver, through hole, PL9823 RGB LEDs for status reporting and SDPT toggle switch to track 3 states. The code runs on a Teensy 3.2 and uses Teensy specific elapsedMillis for loop timing control. The NRF24 uses an SPI interface. It also implements a two-way communication approach with ackn…

teensyNRF24_LEDs_Toggle.ino

#include <SPI.h>
#include <RF24.h>
#include <Adafruit_NeoPixel.h>

// LED Definitions
#define NUM_LEDS 3
#define DATA_PIN 2
#define SWITCH_PIN1 3
#define SWITCH_PIN2 4

// Timing control using elapsedMillis
elapsedMillis radioLedTimer;      // LED0: Radio status update timer (100ms/10Hz)
elapsedMillis switchLedTimer;     // LED1: Switch status update timer (100ms/10Hz)
elapsedMillis blinkLedTimer;      // LED2: Simple blink timer (1000ms/1Hz)
elapsedMillis switchReadTimer;    // Switch reading timer (50ms/20Hz)
elapsedMillis rateCalcTimer;      // Radio rate calculation timer (10s)

Adafruit_NeoPixel strip = Adafruit_NeoPixel(NUM_LEDS, DATA_PIN, NEO_RGB + NEO_KHZ800);

// RF24 Configuration
RF24 radio(7, 8);

// Data structures for communication
struct RadioControlStruct {
    float steering_val;
    float throttle_val;
    float voltage;
    byte estop;
    byte control_mode;
    unsigned long counter;
    uint32_t dummy;
};

struct AckPayloadStruct {
    unsigned long counter;
    uint32_t dummy[4];
};

RadioControlStruct radioData;
AckPayloadStruct ackPayload;

const uint8_t address[][6] = {"RCTRL", "TRACT"};

// Counters and state variables
unsigned long ackCount = 0;
unsigned long shortTermAckCount = 0;
bool led2State = false;

void setup() {
    Serial.begin(115200);
    Serial.println("Starting up...");

    // Initialize LEDs
    strip.begin();
    strip.setBrightness(128);
    strip.show();

    // Initialize switch pins
    pinMode(SWITCH_PIN1, INPUT_PULLUP);
    pinMode(SWITCH_PIN2, INPUT_PULLUP);

    // Initialize SPI and Radio
    SPI.begin();
    delay(100);

    // Try to initialize the radio
    bool initialized = false;
    for (int i = 0; i < 5; i++) {
        if (radio.begin()) {
            initialized = true;
            Serial.println("Radio initialized!");
            break;
        }
        delay(1000);
    }

    if (!initialized) {
        Serial.println("Radio hardware not responding!");
        while (1) {
            strip.setPixelColor(0, 255, 0, 0);
            strip.show();
            delay(500);
            strip.setPixelColor(0, 0, 0, 0);
            strip.show();
            delay(500);
        }
    }

    // Configure radio
    radio.setPALevel(RF24_PA_HIGH);
    radio.setDataRate(RF24_250KBPS);
    radio.setChannel(124);
    radio.openWritingPipe(address[1]);
    radio.openReadingPipe(1, address[0]);
    radio.enableAckPayload();
    radio.startListening();
    radio.printDetails();

    // Initialize acknowledgment payload
    ackPayload.counter = 0;
    for (int i = 0; i < 4; i++) {
        ackPayload.dummy[i] = 0xDEADBEEF;
    }

    Serial.println("Setup complete");
}

void updateRadioLED() {
    if (radioLedTimer >= 100) {  // 10Hz update
        float rate = (float)shortTermAckCount * 10.0; // Convert to Hz
        
        // Set LED0 color based on radio rate
        if (rate < 2.0) {
            strip.setPixelColor(0, 255, 0, 0);  // Red: poor connection
        } else if (rate >= 2.0 && rate <= 5.0) {
            strip.setPixelColor(0, 255, 255, 0);  // Yellow: marginal
        } else {
            strip.setPixelColor(0, 0, 255, 0);  // Green: good connection
        }
        
        shortTermAckCount = 0;
        radioLedTimer = 0;
        strip.show();
    }
}

void updateSwitchLED() {
    if (switchLedTimer >= 100) {  // 10Hz update
        bool state1 = digitalRead(SWITCH_PIN1);
        bool state2 = digitalRead(SWITCH_PIN2);
        
        // Set LED1 color based on switch states
        if (state1 == LOW && state2 == LOW) {
            strip.setPixelColor(1, 255, 0, 0);  // Red
        } else if (state1 == LOW && state2 == HIGH) {
            strip.setPixelColor(1, 0, 0, 255);  // Blue
        } else if (state1 == HIGH && state2 == LOW) {
            strip.setPixelColor(1, 0, 255, 0);  // Green
        } else {
            strip.setPixelColor(1, 0, 0, 0);    // Off
        }
        
        switchLedTimer = 0;
        strip.show();
    }
}

void updateBlinkLED() {
    if (blinkLedTimer >= 1000) {  // 1Hz blink
        led2State = !led2State;
        strip.setPixelColor(2, 0, 0, led2State ? 128 : 0);  // Blue blink
        blinkLedTimer = 0;
        strip.show();
    }
}

void readRadio() {
    if (radio.available()) {
        uint8_t bytes = radio.getDynamicPayloadSize();
        if (bytes == sizeof(RadioControlStruct)) {
            radio.read(&radioData, sizeof(RadioControlStruct));
            
            ackPayload.counter++;
            radio.writeAckPayload(1, &ackPayload, sizeof(AckPayloadStruct));
            
            ackCount++;
            shortTermAckCount++;
        } else {
            radio.flush_rx();
        }
    }
}

void printRadioStats() {
    if (rateCalcTimer >= 10000) {  // Print stats every 10 seconds
        float rate = (float)ackCount / 10.0;  // Convert to Hz
        Serial.print("ACK Rate (Receiver): ");
        Serial.print(rate);
        Serial.println(" Hz");
        
        ackCount = 0;
        rateCalcTimer = 0;
    }
}

void loop() {
    readRadio();
    updateRadioLED();
    updateSwitchLED();
    updateBlinkLED();
    printRadioStats();
}