My third attempt at using an Arduino to make a master clock with dividers and multipliers.
This is a good beginners circuit.
My earlier attempts are here:
You can of course just buy a clock multiplier / divider, but where's the fun in that.
i'M USING a basic Arduino Uno
The OLED communicates via i2c
| Pin | Wiring to Arduino Uno |
| Vin | 5V |
| GND | GND |
| SCL | A5 |
| SDA | A4 |
The POT is wired thus:
centre (wiper) to A0
Right to GND
Left to 5V
The pot supplies an analog voltage which is converted into a digital
signal by the Arduino's ADCs.
Maybe an encoder would be better used??
The 4 LEDs
Cathode to gnd via 220 ohm resistors
Anode to pins 8, 9, 10, 11. I played around with the delay function, but the Millis function works much better.
I'm not a coder so if you can suggest any improvements, let me know.
Feel free to hack & improve the code.
The code:
// &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&
/*
This is part of a project to build a Synth master clock module with multipliers and dividers
Hopefully will add MIDI later.
jondent808@gmail.com
https://djjondent.blogspot.com/2018/03/arduino-index.html
*/
#include <SPI.h>#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
const int ledPin = 8;// the number of the LED pin 8
int ledState = LOW; // ledState used to set the LED 8
const int ledPin9 = 9;// the number of the LED pin 9
int ledState9 = LOW; // ledState used to set the LED 9
const int ledPin10 = 10;// the number of the LED pin 10
int ledState10 = LOW; // ledState used to set the LED 10
const int ledPin11 = 11;// the number of the LED pin 11
int ledState11 = LOW; // ledState used to set the LED 11
#define MIN_BPM 20 /*write here the min BPM that you want */
#define MAX_BPM 300 /* write here the max BPM that you want */
#define POT A0 // the potentiometer connects to analog pin A0
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);
// Variables
int bpm;
unsigned long previousMillis = 0; // will store last time LED was updated
unsigned long previousMillis9 = 0; // will store last time LED9 was updated
unsigned long previousMillis10 = 0; // will store last time LED10 was updated
unsigned long previousMillis11 = 0; // will store last time LED11 was updated
const long interval = 60000; // interval at which to blink (milliseconds)
const long interval2 = 30000; // interval * 2
const long interval4 = 15000; // interval * 4
const long interval8 = 7500; // interval * 8
void setup() {
// set the digital pin as output:
pinMode(ledPin, OUTPUT);
pinMode(ledPin9, OUTPUT);
pinMode(ledPin10, OUTPUT);
pinMode(ledPin11, OUTPUT);
digitalWrite(ledPin,ledState);// set initial state of pin 8 LED
digitalWrite(ledPin9,ledState9);// set initial state of pin 9 LED
digitalWrite(ledPin10,ledState10);// set initial state of pin 10 LED
digitalWrite(ledPin11,ledState11);// set initial state of pin 11 LED
display.begin(SSD1306_SWITCHCAPVCC, 0x3C); // initialize with the I2C addr 0x3C
display.clearDisplay(); // Clear the buffer.
}
void loop() {
bpm = map(analogRead(POT), 0, 1023, MIN_BPM, MAX_BPM);
display.clearDisplay();
display.setTextSize(3);
display.setTextColor(WHITE);
display.setCursor(0,0);
display.println(bpm);
display.setTextSize(2);
display.setTextColor(WHITE);
display.println(" BPM");
display.display();
unsigned long currentMillis = millis();
unsigned long currentMillis9 = millis();
unsigned long currentMillis10 = millis();
unsigned long currentMillis11 = millis();
if (currentMillis - previousMillis >= interval/bpm) {
// save the last time you blinked the LED
previousMillis = currentMillis;
// if the LED 8 is off turn it on and vice-versa:
if (ledState == LOW) {
ledState = HIGH;
} else {
ledState = LOW;
}
// set the LED 8 with the ledState of the variable:
digitalWrite(ledPin, ledState);
}
// **********************************
if (currentMillis9 - previousMillis9 >= interval2/bpm) {
// save the last time you blinked the LED
previousMillis9 = currentMillis9;
// if the LED 9 is off turn it on and vice-versa:
if (ledState9 == LOW) {
ledState9 = HIGH;
} else {
ledState9 = LOW;
}
// set the LED 9 with the ledState of the variable:
digitalWrite(ledPin9, ledState9);
}
// ********************************************
if (currentMillis10 - previousMillis10 >= interval4/bpm) {
// save the last time you blinked the LED
previousMillis10 = currentMillis10;
// if the LED 10 is off turn it on and vice-versa:
if (ledState10 == LOW) {
ledState10 = HIGH;
} else {
ledState10 = LOW;
}
// set the LED 10 with the ledState of the variable:
digitalWrite(ledPin10, ledState10);
}
//*******************************************
if (currentMillis11 - previousMillis11 >= interval8/bpm) {
// save the last time you blinked the LED
previousMillis11 = currentMillis11;
// if the LED 11 is off turn it on and vice-versa:
if (ledState11 == LOW) {
ledState11 = HIGH;
} else {
ledState11 = LOW;
}
// set the LED 11 with the ledState of the variable:
digitalWrite(ledPin11, ledState11);
}
}
// &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&
---------------------------------
-------------------------------------