AutoPlex7 is a simple and versatile Arduino library for controlling seven segment displays with up to four digits. Unlike many other libraries for this purpose, AutoPlex7 automatically multipexes itself using Timer2. This means no calls to refresh the display; enabling AutoPlex7 to work with delays in your code.
- Automatic multiplexing
- Built to work with delays in your code
- Works with both common cathode and common anode displays
- Has a flexible pin layout; letting you connect any display pin to any of Arduino's digital pins
- Built-in, global "display" object
When using AutoPlex7 (or any other direct seven segment display controller software), it is extremely important to use a current limiting resistor in your circuit. Failure to do this can and will damage both the microcontroller and display. With a 5V supply, it is advised to use a resistor of at least 270 ohms on the segment pins.
At the top of your sketch, you'll need to set up a few things for the library to work properly. Firstly, we'll need to state that we are using AutoPlex7, like this.
#include <AutoPlex7.h>Next, let's define a few paremeters. Right under the last line of code, you can tell the Arduino what type of display you're using, like this:
int displayType = COMMON_ANODE;If you're using a common cathode display, just replace "COMMON_ANODE" with "COMMON_CATHODE."
Now, we'll define the digital pins your seven segment display is connected to. We'll start with the digit pins.
int D1 = // Type the digital pin D1 is connected to here;
int D2 = // Type the digital pin D2 is connected to here;
int D3 = // Type the digital pin D3 is connected to here;
int D4 = // Type the digital pin D4 is connected to here;IMPOTANT NOTE: Even if your display does not have four digits, you'll still need to define the pins for the digits you don't have. Just leave these pins unconnected. For instance, if you use a two digit display, you could write that D1 is connnected to pin 1, D2 to 2, D3 to 3, and D4 is 4. You would wire it so that D1 connects to pin 3, and D2 to pin 4. Leave pins 1 and 2 unused. (Essentially, just wire it so that the largest pin number is connected to the same pin in the code as it is in the circuit, and connect each pin moving backwards from there.)
Next, we'll define what Arduino pins the display's segment pins are connected to.
int A = // Type the digital pin A is connected to here;
int B = // Type the digital pin B is connected to here;
int C = // Type the digital pin C is connected to here;
int D = // Type the digital pin D is connected to here;
int E = // Type the digital pin E is connected to here;
int F = // Type the digital pin F is connected to here;
int G = // Type the digital pin G is connected to here;
int DP = // Type the digital pin the decimal point is connected to here;That's it for the paremeters we have to define! Here's an example of what the beginning of a sketch using AutoPlex7 could look like.
#include <AutoPlex7.h>
int displayType = COMMON_CATHODE;
int D1 = 1;
int D2 = 2;
int D3 = 3;
int D4 = 4;
int A = 5;
int B = 6;
int C = 7;
int D = 8;
int E = 9;
int F = 10;
int G = 11;
int DP = 12;After you're done setting up the paremeters, you'll need to initiallize the seven segment display in setup(). This can be done by calling:
display.begin();This will complete the setup process and activate the display.
It's generally recommended that, after calling display.begin() you use the built in display test command to ensure functionality of the display.
display.testDisplay();This will light up all digits, segments, and decimals.
After this, you can use delay(1000) to wait one second, and then clear the display.
display.clearDisplay();This turns off all digits, segments, and decimals. The display is ready for use.
Now that you've initiallized ths display, you can start using it. Let's take a look at the commands you can use to control the screen. We'll start with the most straightforward:
display.showNumber(int number);This command simply shows any number you put in the parenthesis on the screen. For example, if you wish to display "1234," you can do this:
display.showNumber(1234);You can also put a variable in the parenthesis.
display.showNumber(voltageatpinA5);From time to time, you'll need to clear the display. That can be done using:
display.clearDisplay();If you need to show a decimal, you can use these two commands in combination:
display.setDigit(// Choose which digit to show the decimal on by typing it's number);
display.showDecimal():To get rid of a decimal:
display.setDigit(// Choose which digit to clear the decimal on by typing it's number);
display.clearDecimal();MIT License
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