The 7-Segment Display
7-Segment displays are another common component in the world of electronics. These displays have 8 LEDs split into different segments designed to be able to display numerals from 0-9 and a dot. All The LEDs have a common ground / supply line. There are 5 pins at the top and 5 pins at the bottom. The middle pins in the top and bottom are connected to each other internally and have to be connected to Ground / Supply depending upon the type of the 7-segment Display. You can control each segment like an individual LED. However, this method of controlling the 7-segment LED to display numbers would be hectic. So, we will use a technique called Port Manipulation. Pins on the Arduino are grouped together as a PORT. You can control a whole PORT at a time. Read the following write up on the Arduino website before you proceed => Port Manipulation
The 7-Segment Display included in the starter kit is a Common Cathode Type.
First Try the following program that cycles from digits 0 - 9. [SEV_SEG.ino]
Now Try the following program - An extension of our Remote Control Program. Here the Value of the Button being pressed is displayed on the 7-segment display. [SEV_SEG_TSOP.ino]
7-Segment displays are another common component in the world of electronics. These displays have 8 LEDs split into different segments designed to be able to display numerals from 0-9 and a dot. All The LEDs have a common ground / supply line. There are 5 pins at the top and 5 pins at the bottom. The middle pins in the top and bottom are connected to each other internally and have to be connected to Ground / Supply depending upon the type of the 7-segment Display. You can control each segment like an individual LED. However, this method of controlling the 7-segment LED to display numbers would be hectic. So, we will use a technique called Port Manipulation. Pins on the Arduino are grouped together as a PORT. You can control a whole PORT at a time. Read the following write up on the Arduino website before you proceed => Port Manipulation
The 7-Segment Display included in the starter kit is a Common Cathode Type.
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| 7 - Segment LED |
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| Segment & Pin Mapping of a 7-Segment LED / We will be connecting segments A-G & P to digital pins 0-6 & 7 of the Arduino |
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| Place the 7-segment Display on the Breadboard. |
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| Place a 1K resistor between the middle pin on the top and the '-'ve terminal |
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| Connect a Wire from Segment A to digital pin 0 of the Arduino |
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| Connect a Wire from Segment B to digital pin 1 of the Arduino |
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| Connect a Wire from Segment C to digital pin 2 of the Arduino |
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| Connect a Wire from Segment D to digital pin 3 of the Arduino |
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| Connect a Wire from Segment E to digital pin 4 of the Arduino |
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| Connect a Wire from Segment F to digital pin 5 of the Arduino |
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| Connect a Wire from Segment G to digital pin 6 of the Arduino |
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| Connect a Wire from Segment P to digital pin 7 of the Arduino |
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| Our Final Setup with a Program |
/* This is to Display numbers 0-9 on the seven segment LED */ /* Wiring Seg A - Pin 0 Seg B - Pin 1 Seg C - Pin 2 Seg D - Pin 3 Seg E - Pin 4 Seg F - Pin 5 Seg G - Pin 6 Seg H - Pin 7 */ /* To Display '0' we need to make high All Segments except G & H based on this lets make a list of values to write to port D [pins 0-7 are grouped together as port D] When we write a binary value to the port the MSB or the 8th bit will be written to pin 7 and the lsb will be written to pin 0 0 => B00111111 1 => B00000110 2 => B01011011 3 => B01001111 4 => B01100110 5 => B01101101 6 => B01111101 7 => B00000111 8 => B01111111 9 => B01101111 */ int val[]={B00111111,B00000110,B01011011,B01001111,B01100110, B01101101,B01111101, B00000111, B01111111, B01101111}; void setup() { DDRD = B11111111; } void loop() { for(int i=0; i<10;i++) { PORTD = val[i]; delay(1000); } }
Now Try the following program - An extension of our Remote Control Program. Here the Value of the Button being pressed is displayed on the 7-segment display. [SEV_SEG_TSOP.ino]
/* This is to Display numbers 0-9 on the seven segment LED based on Remote Control INPUT */ /* Wiring Seg A - Pin 0 Seg B - Pin 1 Seg C - Pin 2 Seg D - Pin 3 Seg E - Pin 4 Seg F - Pin 5 Seg G - Pin 6 Seg H - Pin 7 */ /* To Display '0' we need to make high All Segments except G & H based on this lets make a list of values to write to port D [pins 0-7 are grouped together as port D] When we write a binary value to the port the MSB or the 8th bit will be written to pin 7 and the lsb will be written to pin 0 0 => B00111111 1 => B00000110 2 => B01011011 3 => B01001111 4 => B01100110 5 => B01101101 6 => B01111101 7 => B00000111 8 => B01111111 9 => B01101111 */ #include <IRremote.h> int RECV_PIN = 12; IRrecv irrecv(RECV_PIN); decode_results results; int remote = 0, display_value=0; int val[]={B00111111,B00000110,B01011011,B01001111,B01100110, B01101101,B01111101, B00000111, B01111111, B01101111}; void setup() { DDRD = B11111111; // Declares PORT D as Output, PORTD is digital pins 0-7 irrecv.enableIRIn(); // Start the receiver } void loop() { if (irrecv.decode(&results)) { remote = results.value; switch(remote) { case 16 : display_value=1; break; case 2064 : display_value=2; break; case 1040 : display_value=3; break; case 3088 : display_value=4; break; case 528 : display_value=5; break; case 2576 : display_value=6; break; case 2960 : display_value=7; break; case 3600 : display_value=8; break; case 272 : display_value=9; break; case 2320 : display_value=0; break; } PORTD = val[display_value]; irrecv.resume(); // Receive the next value } }
