Arduino MKR WiFi 1010 - 10 Segment LED Bar Graph
In this tutorial, we are going to learn:
- How to connect 10 Segment LED Bar Graph to Arduino MKR WiFi 1010
- How to program Arduino MKR WiFi 1010 to control the 10 Segment LED Bar Graph
Hardware Preparation
| 1 | × | Arduino MKR WiFi 1010 | |
| 1 | × | Micro USB Cable | |
| 1 | × | Optionally, DC Power Jack | |
| 1 | × | 10 Segment LED Bar Graph | |
| 10 | × | 220 Ω Resistor | |
| 1 | × | Breadboard | |
| 1 | × | Jumper Wires |
Or you can buy the following kits:
| 1 | × | DIYables Sensor Kit (18 sensors/displays) |
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Additionally, some of these links are for products from our own brand, DIYables .
Additionally, some of these links are for products from our own brand, DIYables .
Overview of 10 Segment LED Bar Graph
| 10 Segment LED Bar Graph | |
|---|---|
| Number of Segments | 10 |
| LED Color | Bright red |
| Forward Voltage | ~2V per segment |
| Forward Current | 20mA max per segment |
| Resistor Required | 220Ω per segment |
Pinout
- Anode pins (A1–A10): each needs to be connected to a GPIO pin via a 220Ω resistor
- Cathode pins (K1–K10): each needs to be connected to GND
Wiring Diagram
Connect the 10 Segment LED Bar Graph to Arduino MKR WiFi 1010 as shown in the table below.
This image is created using Fritzing. Click to enlarge image
| LED Bar Graph | Arduino MKR WiFi 1010 Pin |
|---|---|
| A1 (Anode 1) | Pin 5 (via 220Ω) |
| A2 (Anode 2) | Pin 6 (via 220Ω) |
| A3 (Anode 3) | Pin 7 (via 220Ω) |
| A4 (Anode 4) | Pin 8 (via 220Ω) |
| A5 (Anode 5) | Pin 9 (via 220Ω) |
| A6 (Anode 6) | Pin 10 (via 220Ω) |
| A7 (Anode 7) | Pin 11 (via 220Ω) |
| A8 (Anode 8) | Pin 12 (via 220Ω) |
| A9 (Anode 9) | Pin 13 (via 220Ω) |
| A10 (Anode 10) | Pin 14 (via 220Ω) |
| K1–K10 (Cathodes) | GND |
How To Program Arduino MKR WiFi 1010 for 10 Segment LED Bar Graph
- No library needed: LED Bar Graph uses only the built-in digitalWrite() function
- Define pins: const int ledPins[10] = {5, 6, 7, 8, 9, 10, 11, 12, 13, 14};
- Set each pin as output: pinMode(ledPins[i], OUTPUT);
- Light a segment: digitalWrite(ledPins[i], HIGH);
- Turn off a segment: digitalWrite(ledPins[i], LOW);
Arduino Code - 10 Segment LED Bar Graph
Detailed Instructions
- Connect Arduino MKR WiFi 1010 to PC via Micro USB cable.
- Navigate to the Arduino IDE, then select the board and port.
- Copy the above code and paste it into Arduino IDE.
- Click the Upload button on Arduino IDE to upload code to Arduino MKR WiFi 1010.
- Observe the LED bar graph fill up segment by segment, then empty back down in a repeating animation.
/*
* This Arduino MKR WiFi 1010 code was developed by newbiely.com
*
* This Arduino MKR WiFi 1010 code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/arduino-mkr/arduino-mkr-wifi-1010-10-segment-led-bar-graph
*/
const int NUM_SEGMENTS = 10;
const int ledPins[NUM_SEGMENTS] = {5, 6, 7, 8, 9, 10, 11, 12, 13, 14};
void printBar(int litCount) {
Serial.print("Bar: [");
for (int i = 0; i < NUM_SEGMENTS; i++) {
Serial.print(i < litCount ? "*" : " ");
}
Serial.println("]");
}
void setup() {
Serial.begin(9600);
for (int i = 0; i < NUM_SEGMENTS; i++) {
pinMode(ledPins[i], OUTPUT);
digitalWrite(ledPins[i], LOW);
}
}
void loop() {
for (int i = 0; i < NUM_SEGMENTS; i++) {
digitalWrite(ledPins[i], HIGH);
printBar(i + 1);
delay(100);
}
delay(500);
for (int i = NUM_SEGMENTS - 1; i >= 0; i--) {
digitalWrite(ledPins[i], LOW);
printBar(i);
delay(100);
}
delay(500);
}
Serial Monitor Output
8
Serial.println("Hello World!");
Message (Enter to send message to 'Arduino MKR WiFi 1010' on 'COM15')
New Line
9600 baud
Bar: [* ]
Bar: [** ]
Bar: [*** ]
Bar: [**** ]
Bar: [***** ]
Bar: [****** ]
Bar: [******* ]
Bar: [******** ]
Bar: [********* ]
Bar: [**********]
Bar: [********* ]
Bar: [******** ]
Bar: [******* ]
Bar: [****** ]
Bar: [***** ]
Bar: [**** ]
Bar: [*** ]
Bar: [** ]
Bar: [* ]
Bar: [ ]