/*#############################################################

Program Name    : ex4_KEYPAD_DISCO_F429I_PressAndHoldKeys
Author          : Grant Phillips
Date Modified   : 10/05/2016
Compiler        : ARMmbed
Tested On       : STM32F4-Discovery

Description     : Example program that demonstrates the use of
                  the KEYPAD_DISCO_F429I class to implement a 4x4
                  keypad on the STM32F429I-Discovery board. The
                  characters are added to a string and displayed 
                  as a string as they are pressed. '*' is used 
                  to clear the string. When '#' is held in for 
                  +/- 2 seconds, a '$' will be added to the
                  string.

Requirements    : * STM32F4-Discovery Board
              
Circuit         : * NONE

##############################################################*/
//

#include "mbed.h"
#include "TS_DISCO_F429ZI.h"
#include "LCD_DISCO_F429ZI.h"
#include "KEYPAD_DISCO_F429ZI.h"

KEYPAD_DISCO_F429ZI keypad;
                           
int main() {
    char buf[20];       //string variable
    int bufpos=0;
    char k, key;
    uint32_t holdcounter=0;
    
    keypad.Show(1, 1);                              //Display the keypad, enable the Message and Output Box areas
    keypad.WriteMsgBoxLine(0, "Press keys..(* clear)");    //display a message in the
    keypad.WriteMsgBoxLine(1, "(hold # for surprise)");      //Message Box area of the keypad
   
    while(1) {
        k = keypad.ReadKey();                           //read the current key pressed
        if(k != '\0') {                                 //if a key is pressed
            if(k == '#') {
                holdcounter++;                          //increment a counter while the # key is held in
                if(holdcounter >= 150) {                //a nominal value which the counter much reach to indicate the key was held in long enough
                    holdcounter = 0;                    //reset counter
                    buf[bufpos] = '$';                  
                    buf[bufpos+1] = '\0';               
                    bufpos++;
                    keypad.WriteOutBox(buf);
                }
            }
            else {
                key = k;                                //store the key in a variable
                do                                      //read until key is released
                    k = keypad.ReadKey();
                while(k != '\0');
                
                if(key == '*') {
                    buf[0] = '\0';                      //'clear' the string
                    bufpos = 0;                         //start at character 0
                    keypad.WriteOutBox("              ");   //clear the line
                }
                else {
                    buf[bufpos] = key;                  //add current keypressed to the string
                    buf[bufpos+1] = '\0';               //add NULL to end of string
                    bufpos++;
                }
                keypad.WriteOutBox(buf);                //display result in Output Box area of keypad
            }
        }
        else {
            holdcounter = 0;                            //reset counter when keys are released   
        }
    }
}