Files
JCButton/examples/UpDown/UpDown.ino
2018-05-10 17:37:47 -04:00

88 lines
4.0 KiB
C++

/*----------------------------------------------------------------------*
* Example sketch for Arduino Button Library by Jack Christensen *
* *
* An example that uses both short and long button presses to adjust *
* a number up and down, between two limits. Short presses increment *
* or decrement by one, long presses repeat at a specified rate. *
* Every time the number changes, it is written to the serial monitor. *
* *
* This work is licensed under the Creative Commons Attribution- *
* ShareAlike 3.0 Unported License. To view a copy of this license, *
* visit http://creativecommons.org/licenses/by-sa/3.0/ or send a *
* letter to Creative Commons, 171 Second Street, Suite 300, *
* San Francisco, California, 94105, USA. *
*----------------------------------------------------------------------*/
#include <JC_Button.h> //https://github.com/JChristensen/JC_Button
#define DN_PIN 7 //Connect two tactile button switches (or something similar)
#define UP_PIN 8 //from Arduino pin 7 to ground and from pin 8 to ground.
#define PULLUP true //To keep things simple, we use the Arduino's internal pullup resistor.
#define INVERT true //Since the pullup resistor will keep the pin high unless the
//switch is closed, this is negative logic, i.e. a high state
//means the button is NOT pressed. (Assuming a normally open switch.)
#define DEBOUNCE_MS 25 //A debounce time of 20 milliseconds usually works well for tactile button switches.
#define REPEAT_FIRST 500 //ms required before repeating on long press
#define REPEAT_INCR 100 //repeat interval for long press
#define MIN_COUNT 0
#define MAX_COUNT 59
Button btnUP(UP_PIN, PULLUP, INVERT, DEBOUNCE_MS); //Define the buttons
Button btnDN(DN_PIN, PULLUP, INVERT, DEBOUNCE_MS);
enum {WAIT, INCR, DECR}; //The possible states for the state machine
uint8_t STATE; //The current state machine state
int count; //The number that is adjusted
int lastCount = -1; //Previous value of count (initialized to ensure it's different when the sketch starts)
unsigned long rpt = REPEAT_FIRST; //A variable time that is used to drive the repeats for long presses
void setup()
{
Serial.begin(115200);
}
void loop()
{
btnUP.read(); //read the buttons
btnDN.read();
if (count != lastCount) { //print the count if it has changed
lastCount = count;
Serial.println(count, DEC);
}
switch (STATE) {
case WAIT: //wait for a button event
if (btnUP.wasPressed())
STATE = INCR;
else if (btnDN.wasPressed())
STATE = DECR;
else if (btnUP.wasReleased()) //reset the long press interval
rpt = REPEAT_FIRST;
else if (btnDN.wasReleased())
rpt = REPEAT_FIRST;
else if (btnUP.pressedFor(rpt)) { //check for long press
rpt += REPEAT_INCR; //increment the long press interval
STATE = INCR;
}
else if (btnDN.pressedFor(rpt)) {
rpt += REPEAT_INCR;
STATE = DECR;
}
break;
case INCR: //increment the counter
count = min(count++, MAX_COUNT); //but not more than the specified maximum
STATE = WAIT;
break;
case DECR: //decrement the counter
count = max(count--, MIN_COUNT); //but not less than the specified minimum
STATE = WAIT;
break;
}
}