Initial addition of RTC code -- debugging enabled due to this code being untested

Universal_Serial_Adapter/Project.h

@@ -11,7 +11,7 @@
 #ifndef Project_h
 #define Project_h
 
-#define DEBUG false // For controlling debug output via serial
+#define DEBUG true // For controlling debug output via serial
 
 // Buttons / Joystick / Input Hardware Pinouts
 #define okButtonPin     22

Universal_Serial_Adapter/RTClib.cpp

@@ -0,0 +1,240 @@
+// Code by JeeLabs http://news.jeelabs.org/code/
+// Released to the public domain! Enjoy!
+
+#include <Wire.h>
+#include <avr/pgmspace.h>
+#include "RTClib.h"
+
+#define DS1307_ADDRESS 0x68
+#define SECONDS_PER_DAY 86400L
+
+#define SECONDS_FROM_1970_TO_2000 946684800
+
+#if (ARDUINO >= 100)
+ #include <Arduino.h> // capital A so it is error prone on case-sensitive filesystems
+#else
+ #include <WProgram.h>
+#endif
+
+int i = 0; //The new wire library needs to take an int when you are sending for the zero register
+////////////////////////////////////////////////////////////////////////////////
+// utility code, some of this could be exposed in the DateTime API if needed
+
+const uint8_t daysInMonth [] PROGMEM = { 31,28,31,30,31,30,31,31,30,31,30,31 }; //has to be const or compiler compaints
+
+// number of days since 2000/01/01, valid for 2001..2099
+static uint16_t date2days(uint16_t y, uint8_t m, uint8_t d) {
+    if (y >= 2000)
+        y -= 2000;
+    uint16_t days = d;
+    for (uint8_t i = 1; i < m; ++i)
+        days += pgm_read_byte(daysInMonth + i - 1);
+    if (m > 2 && y % 4 == 0)
+        ++days;
+    return days + 365 * y + (y + 3) / 4 - 1;
+}
+
+static long time2long(uint16_t days, uint8_t h, uint8_t m, uint8_t s) {
+    return ((days * 24L + h) * 60 + m) * 60 + s;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// DateTime implementation - ignores time zones and DST changes
+// NOTE: also ignores leap seconds, see http://en.wikipedia.org/wiki/Leap_second
+
+DateTime::DateTime (uint32_t t) {
+  t -= SECONDS_FROM_1970_TO_2000;    // bring to 2000 timestamp from 1970
+
+    ss = t % 60;
+    t /= 60;
+    mm = t % 60;
+    t /= 60;
+    hh = t % 24;
+    uint16_t days = t / 24;
+    uint8_t leap;
+    for (yOff = 0; ; ++yOff) {
+        leap = yOff % 4 == 0;
+        if (days < 365 + leap)
+            break;
+        days -= 365 + leap;
+    }
+    for (m = 1; ; ++m) {
+        uint8_t daysPerMonth = pgm_read_byte(daysInMonth + m - 1);
+        if (leap && m == 2)
+            ++daysPerMonth;
+        if (days < daysPerMonth)
+            break;
+        days -= daysPerMonth;
+    }
+    d = days + 1;
+}
+
+DateTime::DateTime (uint16_t year, uint8_t month, uint8_t day, uint8_t hour, uint8_t min, uint8_t sec) {
+    if (year >= 2000)
+        year -= 2000;
+    yOff = year;
+    m = month;
+    d = day;
+    hh = hour;
+    mm = min;
+    ss = sec;
+}
+
+static uint8_t conv2d(const char* p) {
+    uint8_t v = 0;
+    if ('0' <= *p && *p <= '9')
+        v = *p - '0';
+    return 10 * v + *++p - '0';
+}
+
+// A convenient constructor for using "the compiler's time":
+//   DateTime now (__DATE__, __TIME__);
+// NOTE: using PSTR would further reduce the RAM footprint
+DateTime::DateTime (const char* date, const char* time) {
+    // sample input: date = "Dec 26 2009", time = "12:34:56"
+    yOff = conv2d(date + 9);
+    // Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 
+    switch (date[0]) {
+        case 'J': m = date[1] == 'a' ? 1 : m = date[2] == 'n' ? 6 : 7; break;
+        case 'F': m = 2; break;
+        case 'A': m = date[2] == 'r' ? 4 : 8; break;
+        case 'M': m = date[2] == 'r' ? 3 : 5; break;
+        case 'S': m = 9; break;
+        case 'O': m = 10; break;
+        case 'N': m = 11; break;
+        case 'D': m = 12; break;
+    }
+    d = conv2d(date + 4);
+    hh = conv2d(time);
+    mm = conv2d(time + 3);
+    ss = conv2d(time + 6);
+}
+
+uint8_t DateTime::dayOfWeek() const {    
+    uint16_t day = date2days(yOff, m, d);
+    return (day + 6) % 7; // Jan 1, 2000 is a Saturday, i.e. returns 6
+}
+
+uint32_t DateTime::unixtime(void) const {
+  uint32_t t;
+  uint16_t days = date2days(yOff, m, d);
+  t = time2long(days, hh, mm, ss);
+  t += SECONDS_FROM_1970_TO_2000;  // seconds from 1970 to 2000
+
+  return t;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// RTC_DS1307 implementation
+
+static uint8_t bcd2bin (uint8_t val) { return val - 6 * (val >> 4); }
+static uint8_t bin2bcd (uint8_t val) { return val + 6 * (val / 10); }
+
+uint8_t RTC_DS1307::begin(void) {
+  return 1;
+}
+
+
+#if (ARDUINO >= 100)
+
+uint8_t RTC_DS1307::isrunning(void) {
+  Wire.beginTransmission(DS1307_ADDRESS);
+  Wire.write(i);	
+  Wire.endTransmission();
+
+  Wire.requestFrom(DS1307_ADDRESS, 1);
+  uint8_t ss = Wire.read();
+  return !(ss>>7);
+}
+
+void RTC_DS1307::adjust(const DateTime& dt) {
+    Wire.beginTransmission(DS1307_ADDRESS);
+    Wire.write(i);
+    Wire.write(bin2bcd(dt.second()));
+    Wire.write(bin2bcd(dt.minute()));
+    Wire.write(bin2bcd(dt.hour()));
+    Wire.write(bin2bcd(0));
+    Wire.write(bin2bcd(dt.day()));
+    Wire.write(bin2bcd(dt.month()));
+    Wire.write(bin2bcd(dt.year() - 2000));
+    Wire.write(i);
+    Wire.endTransmission();
+}
+
+DateTime RTC_DS1307::now() {
+  Wire.beginTransmission(DS1307_ADDRESS);
+  Wire.write(i);	
+  Wire.endTransmission();
+  
+  Wire.requestFrom(DS1307_ADDRESS, 7);
+  uint8_t ss = bcd2bin(Wire.read() & 0x7F);
+  uint8_t mm = bcd2bin(Wire.read());
+  uint8_t hh = bcd2bin(Wire.read());
+  Wire.read();
+  uint8_t d = bcd2bin(Wire.read());
+  uint8_t m = bcd2bin(Wire.read());
+  uint16_t y = bcd2bin(Wire.read()) + 2000;
+  
+  return DateTime (y, m, d, hh, mm, ss);
+}
+
+#else
+
+uint8_t RTC_DS1307::isrunning(void) {
+  Wire.beginTransmission(DS1307_ADDRESS);
+  Wire.send(i);	
+  Wire.endTransmission();
+
+  Wire.requestFrom(DS1307_ADDRESS, 1);
+  uint8_t ss = Wire.receive();
+  return !(ss>>7);
+}
+
+void RTC_DS1307::adjust(const DateTime& dt) {
+    Wire.beginTransmission(DS1307_ADDRESS);
+    Wire.send(i);
+    Wire.send(bin2bcd(dt.second()));
+    Wire.send(bin2bcd(dt.minute()));
+    Wire.send(bin2bcd(dt.hour()));
+    Wire.send(bin2bcd(0));
+    Wire.send(bin2bcd(dt.day()));
+    Wire.send(bin2bcd(dt.month()));
+    Wire.send(bin2bcd(dt.year() - 2000));
+    Wire.send(i);
+    Wire.endTransmission();
+}
+
+DateTime RTC_DS1307::now() {
+  Wire.beginTransmission(DS1307_ADDRESS);
+  Wire.send(i);	
+  Wire.endTransmission();
+  
+  Wire.requestFrom(DS1307_ADDRESS, 7);
+  uint8_t ss = bcd2bin(Wire.receive() & 0x7F);
+  uint8_t mm = bcd2bin(Wire.receive());
+  uint8_t hh = bcd2bin(Wire.receive());
+  Wire.receive();
+  uint8_t d = bcd2bin(Wire.receive());
+  uint8_t m = bcd2bin(Wire.receive());
+  uint16_t y = bcd2bin(Wire.receive()) + 2000;
+  
+  return DateTime (y, m, d, hh, mm, ss);
+}
+
+#endif
+
+
+////////////////////////////////////////////////////////////////////////////////
+// RTC_Millis implementation
+
+long RTC_Millis::offset = 0;
+
+void RTC_Millis::adjust(const DateTime& dt) {
+    offset = dt.unixtime() - millis() / 1000;
+}
+
+DateTime RTC_Millis::now() {
+  return (uint32_t)(offset + millis() / 1000);
+}
+
+////////////////////////////////////////////////////////////////////////////////

Universal_Serial_Adapter/RTClib.h

@@ -0,0 +1,47 @@
+// Code by JeeLabs http://news.jeelabs.org/code/
+// Released to the public domain! Enjoy!
+
+// Simple general-purpose date/time class (no TZ / DST / leap second handling!)
+class DateTime {
+public:
+    DateTime (uint32_t t =0);
+    DateTime (uint16_t year, uint8_t month, uint8_t day,
+                uint8_t hour =0, uint8_t min =0, uint8_t sec =0);
+    DateTime (const char* date, const char* time);
+    uint16_t year() const       { return 2000 + yOff; }
+    uint8_t month() const       { return m; }
+    uint8_t day() const         { return d; }
+    uint8_t hour() const        { return hh; }
+    uint8_t minute() const      { return mm; }
+    uint8_t second() const      { return ss; }
+    uint8_t dayOfWeek() const;
+
+    // 32-bit times as seconds since 1/1/2000
+    long secondstime() const;   
+    // 32-bit times as seconds since 1/1/1970
+    uint32_t unixtime(void) const;
+
+protected:
+    uint8_t yOff, m, d, hh, mm, ss;
+};
+
+// RTC based on the DS1307 chip connected via I2C and the Wire library
+class RTC_DS1307 {
+public:
+  static uint8_t begin(void);
+    static void adjust(const DateTime& dt);
+    uint8_t isrunning(void);
+    static DateTime now();
+};
+
+// RTC using the internal millis() clock, has to be initialized before use
+// NOTE: this clock won't be correct once the millis() timer rolls over (>49d?)
+class RTC_Millis {
+public:
+    static void begin(const DateTime& dt) { adjust(dt); }
+    static void adjust(const DateTime& dt);
+    static DateTime now();
+
+protected:
+    static long offset;
+};

Universal_Serial_Adapter/Universal_Serial_Adapter.ino

@@ -8,7 +8,7 @@
  attribute.
  */
 
-#include <Metro.h>
+#include <Wire.h>
 
 #include "Project.h"
 #include "Config.h"
@@ -26,6 +26,7 @@
 
 UI* ui;
 Config* config;
+RTC_DS1307 rtc;
 
 // helper for interrupt method call
 void processSerial() {
@@ -33,11 +34,26 @@ void processSerial() {
 }
 
 void setup() {
+  // Setup various IO busses
   Serial.begin(115200);
+  Wire.begin();
 
+  // Ensure RTC is set to run on battery
+  // clear /EOSC bit
+  // Sometimes necessary to ensure that the clock
+  // keeps running on just battery power. Once set,
+  // it shouldn't need to be reset but it's a good
+  // idea to make sure.
+  Wire.beginTransmission(0x68); // address DS3231
+  Wire.write(0x0E); // select register
+  Wire.write(0b00011100); // write register bitmap, bit 7 is /EOSC
+  Wire.endTransmission();
+
+  rtc.begin();
+
+  // Stuff used for serial and UI
   config = new Config();
   config->setDefaults();
-
   ui = new UI();
 
   // Setup serial IO on an interrupt timer
@@ -48,6 +64,22 @@ void setup() {
 }
 
 void loop() {
+  if (DEBUG) {
+    DateTime now = RTC.now();
+    Serial.print(now.year(), DEC);
+    Serial.print('/');
+    Serial.print(now.month(), DEC);
+    Serial.print('/');
+    Serial.print(now.day(), DEC);
+    Serial.print(' ');
+    Serial.print(now.hour(), DEC);
+    Serial.print(':');
+    Serial.print(now.minute(), DEC);
+    Serial.print(':');
+    Serial.print(now.second(), DEC);
+    Serial.println();
+  }
+
   // Serial data is processed via an interrupt so isn't needed in the main loop
   ui->processInputEvents();
   ui->processTimeoutEvents();