Published May 9, 2022 © CC BY-SA

FM Radio with Clock Function

Clock radio using the RDA5807M and RTC DS1302

IntermediateProtip4,201

Things used in this project

Hardware components

RDA5807M FM Radio Module

PAM8403 + Volume Control

Arduino Nano

Breadboard and hook up wire

rtc ds1302 module

SSD1306 OLED Display

Software apps and online services

Arduino IDE

Story

I liked the original radio design and use of the miniature RDA5807M Stereo radio module and decided to modify the code and add a clock to the design. After trying to use RDS I realised I needed a way to show the time when the radio is off.. (maybe later adding an alarm to turn it back on).. so I used the RTC DS1302 module to show the time instead. In this project, I assume the DS1302 is already set to the correct time ( covered in the library examples).

When the radio is on, the time is show in small characters on the top of the screen.

When the button is pressed, the radio is turned off and the time, day and date is displayed. I have the radio in stereo mode with a set volume of 8 expecting the PAM8403 module will have a volume control.

The frequency list will have to be edited in the code as these are mine (North West UK)

The RDA5807M module is quite small and requires some ingenuity to adapt it to use with a breadboard.

And of course the processor I used is the Arduino Nano.. although it may be possible to use others (maybe add bluetooth station select).. but i'll leave that to someone else. :)

ps: I added Low-Power in clock mode : Library from GitHub - rocketscream/Low-Power: Low Power Library for Arduino

If You plan to cut the power completely, do it in radio mode. I have found that cutting the power off in clock mode may reset the RTC.. I added a 100uf Capacitor across the power leads on the RTC to allow the data lines to become inactive before the RTC actually powered off. This seemed to help.

When the project is powered from a power bank or computer, the power off is likely to be sudden enough to cause a RTC reset. I found the capacitor held the RTC on just long enough to allow a soft power down while the data lines became inactive.

My completed 3D printed unit. I have provided the stl's as a guide.

The completed circuit board using vero stripboard.

Schematics

Code

Clock Radio Final

#include <Adafruit_SSD1306.h>
#include <Wire.h>
#include <RDA5807M.h>
#include <Arduino.h>
#include <Ds1302.h>
#include <LowPower.h>
#include <SPI.h>
#define OLED_RESET -1
#define FIX_BAND RADIO_BAND_FM   
#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 32 // OLED display heightint setButton = 9;
Ds1302 rtc(8,6,7); // RST , CLK , DAT

int dsplyButton = 11;
int setButton = 9;
int backButton = 10;
int potPin = A0;


float displayStation;
int stationNum, val;

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);
RDA5807M radio;

// Select Your own radio frequencies for your area
int stations[10] = {9110,9370,9580,9670,9740,9890,10040,10540,10590,10760};
const static char* WeekDays[] =
{
    "Monday    ",
    "Tuesday   ",
    "Wednesday ",
    "Thursday  ",
    "Friday    ",
    "Saturday  ",
    "Sunday    "
};
const static char* MonthText[] =
{
    "Jan",
    "Feb",
    "Mar",
    "Apr",
    "May",
    "Jun",
    "Jul",
    "Aug",
    "Sep",
    "Oct",
    "Nov",
    "Dec"
};

void setup() {

  rtc.init();
  pinMode(dsplyButton,INPUT_PULLUP);
  pinMode(setButton,INPUT_PULLUP);
  pinMode(backButton, INPUT_PULLUP);
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C); 
  display.display();
  delay(2000);
  display.clearDisplay();
    
  radio.init();
  radio.setBandFrequency(FIX_BAND, 9110);
  radio.setVolume(8);
  radio.setMono(false);
  radio.setMute(false);
  display.setTextSize(3);
  display.setTextColor(WHITE);
  display.setCursor(20,10);
  display.print("91.10");
  display.display();
}

void loop() {
    radio.setVolume(8);
    Ds1302::DateTime now;
    rtc.getDateTime(&now);
    static uint8_t last_second = 0;
  

       if (last_second != now.second)
    {
        last_second = now.second;
        display.setTextColor(SSD1306_WHITE);
        display.setTextSize(1);
        display.setCursor(40,0);
        if (now.hour <= 9) { //If Hour is single figures, put a 0 in front
        display.print("0");
        }
        display.print(now.hour);
        display.print(":");
     if (now.minute <= 9) {  //If Minute is single figures, put a 0 in front
        display.print("0");
     }
        display.print(now.minute);
        display.print(":"); 
        if (now.second <= 9) {  //If Seconds is single figures, put a 0 in front
        display.print("0");
     } 
        display.print(now.second);

        display.display();
                       
        display.setTextColor(SSD1306_BLACK);
        display.setCursor(40,0);
     if (now.hour <= 9) {
        display.print("0");
    }
       display.print(now.hour);
       display.print(":");
     if (now.minute <= 9) {
       display.print("0");
  }
       display.print(now.minute);
       display.print(":");
     if (now.second <= 9) {
       display.print("0");
  } 
      display.print(now.second); 
  }

    if (digitalRead(backButton)== LOW) {
  
    setFrequency();
}
if (digitalRead(dsplyButton) == LOW) {

  while (digitalRead(dsplyButton) == LOW) {
    
  }

    radio.term();
    DplyClock();

}



}
void setFrequency(){
  display.setTextColor(SSD1306_WHITE);

//  radio.setMute(false);
  while(digitalRead(setButton) == HIGH){
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(0,0);
    display.print("Select Station");
    display.setTextSize(3);
    display.setTextColor(WHITE);
    display.setCursor(20,10);
    val = analogRead(potPin);
    stationNum = map(val, 0, 1023, 0, 9);
    displayStation = stations[stationNum]/100.0;
    display.print(displayStation);
    display.display();
    display.clearDisplay();
  }
  delay(500);
  radio.setBandFrequency(FIX_BAND, stations[stationNum]);
  display.setCursor(20,10);
  display.print(displayStation);
  display.display();
}


void DplyClock() {


    display.clearDisplay();
    while (digitalRead(dsplyButton) == HIGH) {
  
      // get the current time
    Ds1302::DateTime now;
    rtc.getDateTime(&now);
    static uint8_t last_second = 0;
    if (last_second != now.second)
    {
        last_second = now.second;
        display.setTextColor(SSD1306_WHITE);
        display.setTextSize(2);
        display.setCursor(15,2);
        if (now.hour <= 9) { //If Hour is single figures, put a 0 in front
        display.print("0");
        }
        display.print(now.hour);
        display.print(":");
     if (now.minute <= 9) {  //If Minute is single figures, put a 0 in front
        display.print("0");
     }
        display.print(now.minute);
        display.print(":"); 
        if (now.second <= 9) {  //If Seconds is single figures, put a 0 in front
        display.print("0");
     } 
        display.print(now.second);

        display.setTextSize(1);
        display.setCursor(17,22);
        display.print(WeekDays[now.dow -1]);
        display.print(now.day);
        display.print(" ");
        display.print(MonthText[now.month -1]);
        
        display.display();

        
        display.setTextColor(SSD1306_BLACK);
        display.setCursor(17,22);
        display.print(WeekDays[now.dow -1]);
        display.print(now.day);
        display.print(" ");
        display.print(MonthText[now.month -1]);           
        
                
        
        display.setTextSize(2);
        display.setCursor(15,2);
     if (now.hour <= 9) {
        display.print("0");
    }
       display.print(now.hour);
       display.print(":");
     if (now.minute <= 9) {
       display.print("0");
  }
       display.print(now.minute);
       display.print(":");
     if (now.second <= 9) {
       display.print("0");
  } 
      display.print(now.second);
  
}
    LowPower.powerDown(SLEEP_250MS,ADC_OFF,BOD_OFF);  // Sleep for 250MS/Sec in Low Power
}
while (digitalRead(dsplyButton) == LOW){
  }
  display.setTextColor(SSD1306_WHITE);
  radio.init();
  radio.setBandFrequency(FIX_BAND, stations[stationNum]);
  display.clearDisplay();
  display.setTextSize(3);
  display.setCursor(20,10);
  stationNum = map(val, 0, 1023, 0, 9);
  displayStation = stations[stationNum]/100.0;
  display.print(displayStation);
  display.display();
}

Credits

stevie135s

25 projects • 11 followers

Neeraj Rane

18 projects • 47 followers

Electrical Engineer and a Maker from India. Engineering is fun once you start applying it!

FM Radio with Clock Function

Things used in this project

Hardware components

Software apps and online services

Story

Custom parts and enclosures

Radio Housing

Radio Fascia

Schematics

Clock Radio Wiring Diagram

Vero Schematic

Code

Clock Radio Final

Credits

stevie135s

Neeraj Rane

Comments

Embed the widget on your own site

FM Radio with Clock Function

FM Radio with Clock Function

Things used in this project

Hardware components

Software apps and online services

Story

Custom parts and enclosures

Radio Housing

Radio Fascia

Schematics

Clock Radio Wiring Diagram

Vero Schematic

Code

Clock Radio Final

Credits

stevie135s

Neeraj Rane

Comments

Related channels and tags