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Hello Digilent community, I am currently taking my first digital electronics class and my final project is a calculator written in VHDL using a Basys3 board, 16-key keypad, and a 16x2 LCD display with parallel interface, all provided by Digilent. I took a look at the provided example code from the resource library and I just had some questions about how it works. Now, the example code declares a constant before any of the processes, and this constant is an array of std_logic_vectors so it holds a preloaded message "Hello From Digilent" with the necessary function sets and all that preceding the message. In my case, I have to have a way to display the inputs from the keypad on the display and also display the output on the 2nd line of the display. I have the main logic part of the calculator settled, I just want to know how I can direct these signals from the keypad and the output of the computational module (as in the sum, difference, product, etc.) to the LCD display. I have never played with a display before now and never used VHDL or any type of board like the Basys3 before this class, so I guess I'm still quite novice and don't understand a good part of what the example code is telling me. I do get that the state machine is just cycling through the values in the constant and waits for certain delays to pass through before transitioning between certain states. Since the values on the display have to be updated live as the user inputs numbers from the keypad and also when there is a value computed, how can I shift from having a constant with a preloaded message to something that can update itself as needed? My idea was keep the idea of the array of std_logic_vectors but only have one value (rather than the 23 or 24 that are preloaded in the current example code) that will update with every key press. I'll have two of these, one for the inputs (to show the numbers and operations on the first line) and one for the output (to show on the second line). I'm thinking maybe I declare a variable within a process that will update and be sensitive to the key presses? Also, I tried looking around the reference manual and such but I could not find the function code for how to display information on the 2nd line; so far, stuff only displays on the first line. Sorry this is such a bulky post. I have had a lot of questions and my professor hasn't been around much. Also, part of this project is learning to interface with new components, so in my case the keypad and lcd display, and I'm not having much luck without any guidance unfortunately. Thank you for taking the time to read this! P.S. Attached the example vhd file from Digilent here for easy access in case anyone wants to look! PmodCLP.vhd