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simpleclock/simpleclock.ino
eleksir ccb12d2076 Move Time Compensation feature under define
* move Time Compensation feature under define
* translte last few eol to unix style
* make correction: in my case with bad chrystal rtc runs faster about
  9.5 seconds per day
2019-10-07 03:02:25 +03:00

302 lines
8.4 KiB
C++

/*
* 7 Segment 4 Digits clock with digit point separator
*
* It uses display module with common anode and DS1307 RTC module to enhance
* time keeping ability of Atmega 328p based Arduino Nano microcontroller and
* 2 buttons for adjusting time.
*/
/* DS1307 lib by FrankieChu for Seeed RTC module, in my case
* Grove___RTC_DS1307-1.0.0.zip */
#include <DS1307.h>
#include <SevSeg.h>
/* disable time compensation
* as we borrow more accurate chrystal and solder it to rtc breakboard
*/
//#define TIMECOMP
/* 0.5 second/day compensation flag */
//#define OFIVECOMP
#define cbi(sfr, bit) (_SFR_BYTE(sfr) &= ~_BV(bit))
#define sbi(sfr, bit) (_SFR_BYTE(sfr) |= _BV(bit))
DS1307 clock;
SevSeg Display;
/* push button stuff */
const long initial_delay = 600; // wait a bit before spin numbers
const long adjust_interval = 200; // delay between consecutive number increments
const long bounce_delay = 20; // contact bounce compensation
const int hrs_btn = A0; // put hour adjusting button on A0 lane
const int min_btn = A1; // put minute adjusting button on A1 lane
volatile bool btn_pushed = false; // is button pushed?
unsigned long previousPushTimer = 0;
/* dot blinking stuff */
volatile bool dot = true;
#ifdef TIMECOMP
/* time inaccuracy compensation flag */
volatile bool compflag1 = true;
volatile bool compflag2 = false;
const uint8_t timeSkew = 9; // assume that clock runs faster than should
#ifdef OFIVECOMP
volatile bool timeSkewEven = false; // comp. 1 additional second per 2 days
#endif
#endif
/* ambient light compensation aka night mode */
const int photoPin = A2;
volatile bool measureAmbLight = true;
unsigned int ambLight = 0;
unsigned long previousLightTimer = 0;
const long refresh_interval = 40; // refresh rate 25Hz
/* time vars */
volatile uint8_t mysecond;
volatile uint8_t myminute;
volatile uint8_t myhour;
/* rtc sync flag */
volatile bool rtcsync = true;
void setup()
{
// setup display
byte hardwareConfig = COMMON_ANODE;
byte numDigits = 4;
byte digitPins[] = {9, 10, 11, 12};
byte segmentPins[] = {2, 3, 4, 5, 6, 7, 8, 13};
bool resistorsOnSegments = true; // 8 resistors, 330 Ohms each
/* updateWithDelays defaults to false and it is recommended value,
* but i was unable to make my display to change brightness notably with
* recommended value, so i have to use updateWithDelays=true,
* in this case brightness gets changed.
*/
bool updateWithDelays = true;
/* without it there is visual bug at 0 o'clock, and in current version
* of SevSeg' setChars() does not dots at all */
bool leadingZeros = false;
Display.begin(hardwareConfig, numDigits, digitPins, segmentPins,
resistorsOnSegments, updateWithDelays, leadingZeros);
Display.setBrightness(100);
// setup clock
clock.begin();
// if rtc returns incorrect time, reset it to some default value
clock.getTime();
if ((clock.hour > 23) || (clock.minute > 59)) {
clock.fillByYMD(2019, 2, 23); // 23 Feb 2019
clock.fillByHMS(15, 52, 30); // 15:52:30"
clock.fillDayOfWeek(SAT); // Saturday
clock.setTime(); // put date to rtc
}
// setup control buttons
pinMode(hrs_btn, INPUT_PULLUP);
pinMode(min_btn, INPUT_PULLUP);
/* Timer stuff
* timer0 being used in millis() micros() delay() etc, it has 8 bit resolution
* timer2 being used in analogWrite() tone() notone(), it has 8 bit resolution
* timer1 being used in servo lib has 16 bit resolution
* We'll use timer1, since we have no mechanical parts and don't need servo lib
*/
// initialize timer1
noInterrupts(); // disable all interrupts
TCCR1A = 0;
TCCR1B = 0;
TCNT1 = 34286; // preload timer 65536-16MHz/256/2Hz
TCCR1B |= (1 << CS12); // 256 prescaler
TIMSK1 |= (1 << TOIE1); // enable timer overflow interrupt
interrupts(); // enable all interrupts
/* increase sampling rate of analogRead()
* by setting an ADC prescale from 128 to 16, so it takes less time to read
* sensor
*/
sbi(ADCSRA, ADPS2);
cbi(ADCSRA, ADPS1);
cbi(ADCSRA, ADPS0);
// setup ambient brigtness sensor
pinMode(photoPin, INPUT);
ambLight = analogRead(photoPin);
}
ISR(TIMER1_OVF_vect)
{
/* Feed clock twice per second */
TCNT1 = 34286; // preload timer
// do not read rtc if time beng adjusted by buttons
(btn_pushed) ? rtcsync : rtcsync = true;
/* Also switch dot */
if (dot)
dot = false;
else
dot = true;
#ifdef TIMECOMP
/* time compensation magic */
if ((myhour == 21) and (myminute == 21) and (mysecond == 21)
and (compflag2)) {
compflag1 = true;
#ifdef OFIVECOMP
(timeSkewEven) ? timeSkewEven = false : timeSkewEven;
#endif
}
if ((myhour == 21) and (myminute == 21) and (mysecond == 23)) {
compflag1 = false;
compflag2 = true;
}
#endif
}
void loop()
{
unsigned long currentMillis = millis();
#ifdef TIMECOMP
/*
* Let's implement time compenstion for individual rtc module time
* charachteristics. In in my case quartz resonator as inaccurate as
* about +9.5 seconds per 24 hours
*/
if (compflag1 && compflag2) {
#ifdef OFIVECOMP
if (timeSkewEven) {
clock.fillByHMS(myhour, myminute, (mysecond - timeSkew - 1));
} else {
#endif
clock.fillByHMS(myhour, myminute, (mysecond - timeSkew));
#ifdef OFIVECOMP
}
#endif
clock.setTime();
compflag2 = false;
}
#endif
if (rtcsync) {
clock.getTime();
mysecond = clock.second;
myminute = clock.minute;
myhour = clock.hour;
updateTimeStr(myhour, myminute);
rtcsync = false;
}
// push button magic
if ((!btn_pushed) and
((digitalRead(hrs_btn) == LOW) or (digitalRead(min_btn) == LOW))) {
if (currentMillis - previousPushTimer >= initial_delay) {
previousPushTimer = currentMillis;
btn_pushed = true;
}
}
if (btn_pushed and
(digitalRead(hrs_btn) != LOW) and (digitalRead(min_btn) != LOW)) {
// compensate possible contact bounce with delay
if (currentMillis - previousPushTimer >= bounce_delay) {
btn_pushed = false;
}
}
if (btn_pushed) {
if (currentMillis - previousPushTimer >= adjust_interval) {
previousPushTimer = currentMillis;
if (digitalRead(hrs_btn) == LOW) {
myhour++;
(myhour > 23) ? myhour = 0 : myhour;
clock.fillByHMS(myhour, myminute, 0);
clock.setTime();
}
if (digitalRead(min_btn) == LOW) {
myminute++;
(myminute > 59) ? myminute = 0 : myminute;
clock.fillByHMS(myhour, myminute, 0);
clock.setTime();
}
}
updateTimeStr(myhour, myminute);
}
if ((currentMillis - previousLightTimer >= refresh_interval) or
(previousLightTimer > currentMillis)) { // millis() reset every ~49 days
previousLightTimer = currentMillis;
ambLight = analogRead(photoPin);
/* Ambient light compensation
* ambLight can be in range of 0..1023, if it 910+, it has point to use
* fullbright.
* Use table comparsion (not function of ambLight) because of non-linear
* charachteristics of led indicator, that cannot be described via simple
* formula.
*/
if (ambLight >= 910) {
Display.setBrightness(100);
} else if ((ambLight < 900) and (ambLight >= 860)) {
Display.setBrightness(75);
} else if ((ambLight < 850) and (ambLight >= 810)) {
Display.setBrightness(45);
} else if ((ambLight < 800) and (ambLight >= 760)) {
Display.setBrightness(25);
} else if ((ambLight < 750) and (ambLight >= 710)) {
Display.setBrightness(18);
} else if ((ambLight < 700) and (ambLight >= 660)) {
Display.setBrightness(12);
} else if ((ambLight < 650) and (ambLight >= 610)) {
Display.setBrightness(10);
} else if ((ambLight < 600) and (ambLight >= 560)) {
Display.setBrightness(7);
} else if ((ambLight < 550) and (ambLight >= 410)) {
Display.setBrightness(4);
} else if ((ambLight < 400) and (ambLight >= 360)) {
Display.setBrightness(0);
} else if ((ambLight < 350) and (ambLight >= 310)) {
Display.setBrightness(-3);
} else if ((ambLight < 300) and (ambLight >= 260)) {
Display.setBrightness(-6);
} else if ((ambLight < 250) and (ambLight >= 210)) {
Display.setBrightness(-10);
} else if ((ambLight < 200) and (ambLight >= 160)) {
Display.setBrightness(-14);
} else if ((ambLight < 150) and (ambLight >= 110)) {
Display.setBrightness(-18);
} else if (ambLight < 100) {
Display.setBrightness(-22);
}
}
Display.refreshDisplay();
}
void updateTimeStr(uint8_t h, uint8_t m)
{
if (dot) {
char str[5];
sprintf(str, "%2d.%02d", h, m);
Display.setChars(str);
} else {
char str[4];
sprintf(str, "%2d%02d", h, m);
Display.setChars(str);
}
}
/* vim: set filetype=cpp: */