Arduino Menu System 16x2 LCD Display

Arduino Menu System 16x2 LCD Display

I was looking for a simple menu system for a 16x2 LCD with a setup mode and a running mode.

What i took was the core code developed by 'polepole' on the Arduino forums and have adapted it and documented as best as I can.

Compiled and uploaded it uses 3 buttons up, down and select  - to enter the menu system press the up and down together as the arduino is rebooted. Once completed in the setup function it then drops out to the main void loop.

Ive tried to comment it as much as is sensible in order to help another plagarist like me to hack it into what they need.

Also given some rough guide on how to switch it to running as a menu based app i.e. the Menu is the core code and not a setup function.

I am no professional coder and generally look for snippets of code other have produced learning from them to achieve what I need.

Code posted below

Hope someone finds it useful

//Define Various Variables used throughout int timer = 0; byte totalRows = 2; // total rows of LCD byte totalCols = 16; // total columns of LCD int returndata = 0; // Used for return of button presses unsigned long timeoutTime = 0; // this is set and compared to millis to see when the user last did something. const int menuTimeout = 20000; // time to timeout in a menu when user doesn't do anything. unsigned long lastButtonPressed; // this is when the last button was pressed. It's used to debounce. const int debounceTime = 150; // this is the debounce and hold delay. Otherwise, you will FLY through the menu by touching the button. const int buttonUp = 8; // Set pin for UP Button const int buttonDown = 9; // Set pin for DOWN Button const int buttonSelect = 11; // Set pin for SLELECT Button const int buttonCancel = 12; // Set pun for CANCEL Button (No currently used) int buttonStateUp = 0; // Initalise ButtonStates int buttonStateDown = 0; int buttonState; int count = 0; // Temp variable for void demo // constants for indicating whether cursor should be redrawn #define MOVECURSOR 1 // constants for indicating whether cursor should be redrawn #define MOVELIST 2 // Main setup routine void setup() { // Setup stuff that needs to be done regardless of whether entering setup mode or not // set up the LCD's number of columns and rows: lcd.begin(totalCols, totalRows); // Turn on the LCD Backlight lcd.setLED1Pin(1); // initialize the serial communications port: Serial.begin(9600); // Set Buttons as input for testing whether to enter setup mode pinMode(buttonUp, INPUT); pinMode(buttonDown, INPUT); // Read the Button States buttonStateUp = digitalRead(buttonUp); buttonStateDown = digitalRead(buttonDown); // Start Setup Mode if both up and down buttons pressed together if (buttonStateUp == HIGH && buttonStateDown == HIGH) { byte topItemDisplayed = 0; // stores menu item displayed at top of LCD screen byte cursorPosition = 0; // where cursor is on screen, from 0 --> totalRows. // redraw = 0 - don't redraw // redraw = 1 - redraw cursor // redraw = 2 - redraw list byte redraw = MOVELIST; // triggers whether menu is redrawn after cursor move. byte i=0; // temp variable for loops. byte totalMenuItems = 0; //a while loop below will set this to the # of menu items. // Create list of Menu Items char* menuItems[]={ "Menu Item 1", "Menu Item 2", "Menu Item 3", "Menu Item 4 ", "Menu Item 5", "Menu Item 6", "", }; // count how many items are in list. while (menuItems[totalMenuItems] != ""){ totalMenuItems++; } //subtract 1 so we know total items in array. totalMenuItems--; lcd.clear(); // clear the screen so we can paint the menu. boolean stillSelecting = true; // set because user is still selecting. timeoutTime = millis() + menuTimeout; // set initial timeout limit. do // Run a loop while waiting for user to select menu option. { // Call any other setup actions required and/or process anything else required whilst in setup mode as opposed to things setup regardless of setup mode // Call read buttons routine which analyzes buttons and gets a response. Default response is 0. switch(read_buttons()) { // Case responses depending on what is returned from read buttons routine case 1: // 'UP' BUTTON PUSHED timeoutTime = millis()+menuTimeout; // reset timeout timer // if cursor is at top and menu is NOT at top // move menu up one. if(cursorPosition == 0 && topItemDisplayed > 0) // Cursor is at top of LCD, and there are higher menu items still to be displayed. { topItemDisplayed--; // move top menu item displayed up one. redraw = MOVELIST; // redraw the entire menu } // if cursor not at top, move it up one. if(cursorPosition>0) { cursorPosition--; // move cursor up one. redraw = MOVECURSOR; // redraw just cursor. } break; case 2: // 'DOWN' BUTTON PUSHED timeoutTime = millis()+menuTimeout; // reset timeout timer // this sees if there are menu items below the bottom of the LCD screen & sees if cursor is at bottom of LCD if((topItemDisplayed + (totalRows-1)) < totalMenuItems && cursorPosition == (totalRows-1)) { topItemDisplayed++; // move menu down one redraw = MOVELIST; // redraw entire menu } if(cursorPosition<(totalRows-1)) // cursor is not at bottom of LCD, so move it down one. { cursorPosition++; // move cursor down one redraw = MOVECURSOR; // redraw just cursor. } break; case 4: // SELECT BUTTON PUSHED timeoutTime = millis()+menuTimeout; // reset timeout timer switch(topItemDisplayed + cursorPosition) // adding these values together = where on menuItems cursor is. { case 0: // menu item 1 selected lcd.clear(); lcd.print("Run Item1 code"); lcd.setCursor(0,1); lcd.print("from here"); Serial.print("Menu item "); Serial.print(topItemDisplayed + cursorPosition); Serial.print(" selected - "); Serial.println(menuItems[topItemDisplayed + cursorPosition]); delay(2000); stillSelecting = false; break; case 1: // menu item 2 selected lcd.clear(); lcd.print("Run Item2 code"); lcd.setCursor(0,1); lcd.print("from here"); Serial.print("Menu item "); Serial.print(topItemDisplayed + cursorPosition); Serial.print(" selected - "); Serial.println(menuItems[topItemDisplayed + cursorPosition]); break; case 2: // menu item 3 selected lcd.clear(); lcd.print("Run Item3 code"); lcd.setCursor(0,1); lcd.print("from here");Serial.print("Menu item "); Serial.print(topItemDisplayed + cursorPosition); Serial.print(" selected - "); Serial.println(menuItems[topItemDisplayed + cursorPosition]); break; case 3: // menu item 4 selected lcd.clear(); lcd.print("Run Item4 code"); lcd.setCursor(0,1); lcd.print("from here");Serial.print("Menu item "); Serial.print("Menu item "); Serial.print(topItemDisplayed + cursorPosition); Serial.print(" selected - "); Serial.println(menuItems[topItemDisplayed + cursorPosition]); break; case 4: // menu item 5 selected lcd.clear(); lcd.print("Run Item5 code"); lcd.setCursor(0,1); lcd.print("from here");Serial.print("Menu item ");Serial.print("Menu item "); Serial.print(topItemDisplayed + cursorPosition); Serial.print(" selected - "); Serial.println(menuItems[topItemDisplayed + cursorPosition]); break; case 5: // menu item 6 selected lcd.clear(); lcd.print("Run Item6 code"); lcd.setCursor(0,1); lcd.print("from here");Serial.print("Menu item "); Serial.print("Menu item "); Serial.print(topItemDisplayed + cursorPosition); Serial.print(" selected - "); Serial.println(menuItems[topItemDisplayed + cursorPosition]); break; } break; //case 8: // CANCEL BUTTON PUSHED - Not currently used // stillSelecting = false; // Serial.println("Button held for a long time"); // break;