rotary encoder lcd display in stock

I have taken two example and put them together but there is some issues, for instance is very unstable to get into the menus, also if I spin the rotary encoder more than I have cover I will not get values, is there something already done to be used here I don"t want to re invent the wheel, thanks for you help.

In this tutorial we will learn how rotary encoder works and how to use it with Arduino. You can watch the following video or read the written tutorial below.

A rotary encoder is a type of position sensor which is used for determining the angular position of a rotating shaft. It generates an electrical signal, either analog or digital, according to the rotational movement.

There are many different types of rotary encoders which are classified by either Output Signal or Sensing Technology. The particular rotary encoder that we will use in this tutorial is an incremental rotary encoder and it’s the simplest position sensor to measure rotation.

Let’s take a closer look at the encoder and see its working principle. Here’s how the square wave pulses are generated: The encoder has a disk with evenly spaced contact zones that are connected to the common pin C and two other separate contact pins A and B, as illustrated below.

We can notice that the two output signals are displaced at 90 degrees out of phase from each other. If the encoder is rotating clockwise the output A will be ahead of output B.

So if we count the steps each time the signal changes, from High to Low or from Low to High, we can notice at that time the two output signals have opposite values. Vice versa, if the encoder is rotating counter clockwise, the output signals have equal values. So considering this, we can easily program our controller to read the encoder position and the rotation direction.

Description of the code: So first we need to define the pins to which our encoder is connected and define some variables needed for the program. In the setup section we need to define the two pins as inputs, start the serial communication for printing the results on the serial monitor, as well as read the initial value of the output A and put the value into the variable aLastState.

Then in the loop section we read the output A again but now we put the value into the aState variable. So if we rotate the encoder and a pulse is generated, these two values will differ and the first “if” statement will become true. Right after that using the second “if” statement we determine the rotation direction. If the output B state differ from the output A state the counter will be increased by one, else it will be decreased. At the end, after printing the results on the serial monitor, we need to update the aLastState variable with aState variable.

That’s all we need for this example. If upload the code, start the Serial Monitor and start rotating the encoder we will start getting the values in the serial monitor. The particular module that I have makes 30 counts each full cycle.

At first we are going to take a look at the drawMenu function. This function is responsible for drawing the Menu on the display. This function is called every few milliseconds, so if there is a change on the menu this function is responsible for updating the menu on the screen.

There are also 3 very important global variables, the variable page, the variable menuitem and variable frame. The variable page remembers which UI screen is displayed on the screen. So, if the page variable is 1, we are in the main UI screen, and if the variable is 2 we are in the secondary UI screen where we set the value on a variable. The menu item remembers the selected menu item. So, if its value is 1, the first menu item is selected, so the drawMenu function must draw this menu item as black with white letters. If the menu item is 2 the second menu item is selected and so on. The frame variable, remembers which part of the menu is displayed on the screen. Since the menu we have created contains 6 items and we can only display 3 of them at a time, we need to know which items are displayed on the screen. The frame variable, tells us exactly this. If the frame variable has the value of 1, we display the first three menu items, if it is 2, we display items 2,3,4 and so on.

At first we initialize all the global variables that are needed in the code. Next we initialize the display. In the loop function, at first we call the drawMenu function to draw the menu on the screen. Then we read the value from the Rotary encoder and check if the button is pressed. For example, if we are on the main UI screen and the first menu item is selected, if the value from the rotary encoder has increased, the menuitem variable increases and in the next loop the drawMenu function will draw the second menu item as selected. If we now press the button of the rotary encoder we navigate to the second page, where we set the value of the variable. Again using the rotary encoder we can increase or decrease the value of the variable. If we press the button we navigate back to the main menu page, and page variable decreases.

Rotary encoders are used in the myriad of common devices we see every day. From printers and photographic lenses to CNC machines and robotics, rotary encoders are closer to us than we think. The most popular example of the use of a rotary encoder in everyday life is the volume control knob of a car radio.

A rotary encoder is a type of position sensor that converts the angular position (rotation) of a knob into an output signal that is used to determine which direction the knob is being turned.

There are two types of rotary encoders – absolute and incremental. The absolute encoder reports the exact position of the knob in degrees while the incremental encoder reports how many increments the shaft has moved.

Potentiometers are used in situations where you need to know the exact position of the knob. Whereas, rotary encoders are used in situations where you need to know the change in position rather than the exact position.

Let’s connect the rotary encoder to the Arduino. The connections are quite simple. Start by connecting the +V pin on the module to 5V on the Arduino and the GND pin to Ground.

In the setup section, we first configure the connections to the rotary encoder as inputs, then we enable the input pullup resistor on the SW pin. We also setup the serial monitor.

When a change occurs, the function updateEncoder() (known as the Interrupt Service Routine or just ISR) is called automatically. The code within this function is executed and then the program returns back to what it was doing before.

Here is the sketch to precisely control the servo motor with the rotary encoder. Each time the knob is rotated one detent (click) the position of the servo arm will change by one degree.

I love this. Great job! I am in the process of trying to figure out how to do this EXACT same thing and am looking for some help. I have a Raspberry Pi running OSMC and I am trying to find a source to learn how to code the rotary encoders I have. I want 1 of the encoders to scroll and select the menu and the other to control the volume. This project is going inside an old 1941 Zenith radio. I would really appreciate any thoughts you may have or if you might be interested in taking a stab yourself. Please let me know either way.