Diff: PCF8583_rtc.cpp

Revision:

0:f09cf90def53

Child:

1:a8b9fb95696b

diff -r 000000000000 -r f09cf90def53 PCF8583_rtc.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/PCF8583_rtc.cpp	Sun Feb 09 00:25:21 2014 +0000
@@ -0,0 +1,403 @@
+/*********************************************************************************
+ * An mbed class to control the PCF8583 Real time Clock/Calender
+ * Copyright (c) 2014 Dennis (Denny) Smith - dennyem
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * 13.01.14    initial design for PIC devices using PICC compiler
+ * 21.01.14    ported to mBed LPC1768 in 'C'
+ * 09.02.14    converted to C++ and ported to mBed LPC812
+ *
+ * TODO
+ *       write function is still to be tested
+ *       WriteNVram function is still to be tested
+ *       ReadNVram function is still to be tested
+ *       FormatDateTime needs am/pm, 12/24 hour parsing
+ *       Alarm functions not yet implemented
+*/
+
+#include <mbed.h>
+#include <PCF8583_rtc.h>
+
+//-----------------------------------------------------------------------------
+// constructor -- accepts an I2c object to use for connection with the rtc
+PCF8583rtc::PCF8583rtc(I2C *i2c)
+{
+   _i2c = i2c;
+      
+  ShortDateFormat = "d,m,yy";
+  LongDateFormat  = "dddd dd mmmm yyyy";
+  ShortTimeFormat = "d:m:yy";
+  LongTimeFormat  = "dd:nn:yyyy";
+
+  DateSeparator   = '/';
+  TimeSeparator   = ':';
+
+  ShortDayNames[0] = "Mon";
+  ShortDayNames[1] = "Tue";
+  ShortDayNames[2] = "Wed";
+  ShortDayNames[3] = "Thu";
+  ShortDayNames[4] = "Fri";
+  ShortDayNames[5] = "Sat";
+  ShortDayNames[6] = "Sun";
+
+  LongDayNames[0]  = "Monday";
+  LongDayNames[1]  = "Tuesday";
+  LongDayNames[2]  = "Wednesday";
+  LongDayNames[3]  = "Thursday";
+  LongDayNames[4]  = "Friday";
+  LongDayNames[5]  = "Saturday";
+  LongDayNames[6]  = "Sunday";
+
+  ShortMonthNames[0] = "Jan";
+  ShortMonthNames[1] = "Feb";
+  ShortMonthNames[2] = "Mar";
+  ShortMonthNames[3] = "Apr";
+  ShortMonthNames[4] = "May";
+  ShortMonthNames[5] = "Jun";
+  ShortMonthNames[6] = "Jul";
+  ShortMonthNames[7] = "Aug";
+  ShortMonthNames[8] = "Sep";
+  ShortMonthNames[9] = "Oct";
+  ShortMonthNames[10] = "Nov";
+  ShortMonthNames[11] = "Dec";
+
+  LongMonthNames[0]  = "January";
+  LongMonthNames[1]  = "February";
+  LongMonthNames[2]  = "March";
+  LongMonthNames[3]  = "April";
+  LongMonthNames[4]  = "May";
+  LongMonthNames[5]  = "June";
+  LongMonthNames[6]  = "July";
+  LongMonthNames[7]  = "August";
+  LongMonthNames[8]  = "September";
+  LongMonthNames[9]  = "October";
+  LongMonthNames[10]  = "November";
+  LongMonthNames[11]  = "December";
+};
+
+void PCF8583rtc::write(const char address)
+{
+    pauseCounting();    //Must stop counting before initialising Date/time
+
+    _i2c->start();                                                 // Issue start signal
+    _i2c->write(Write_addr);                                       // Address PCF8583, see PCF8583 datasheet
+    _i2c->write(address);                                          // Address is 1 for Time or 10 for Alarm
+    _i2c->write(dt.time.hundreds);                                 // Hundredths of a second
+    _i2c->write(dt.time.seconds);                                  // Seconds
+    _i2c->write(dt.time.minutes);                                  // Minutes
+    _i2c->write(dt.time.hours);                                    // Hours
+    _i2c->write(dt.date.day & 0x3F);                               // Always set the 3 year bits to 0
+
+    if(address == TIME)
+        _i2c->write(((dt.date.weekday & 7) << 5 )| dt.date.month); // Weekday/month
+    else
+        _i2c->write(dt.date.month & 0x1f);                         // No Weekday for alarm
+
+    _i2c->stop();                                                  // Issue stop signal
+
+    if(address == TIME) {
+        writeByte(CENTURY_REG, dt.date.century);                 // Store the full 4 digit year in NV Ram
+        writeByte(YEAR_REG, dt.date.year);
+    };
+
+    enableCounting();
+};
+
+//--------------------- Reads time and date information from RTC (PCF8583)
+void PCF8583rtc::read(const char address)
+{
+    char tmp[8];
+    char year_bits = 0;                // To test for year change
+
+    tmp[0] = address;
+    _i2c->write(PCF8583_addr, tmp, 1); // Address PCF8583, see PCF8583 datasheet
+    _i2c->read(PCF8583_addr, tmp, 6);  // Address PCF8583 for reading R/W=1
+    
+    dt.time.hundreds   = ((tmp[0] & 0xF0) >> 4) * 10 + (tmp[0] & 0x0F);   // Transform hundredths of seconds
+    dt.time.seconds    = ((tmp[1] & 0xF0) >> 4) * 10 + (tmp[1] & 0x0F);   // Transform seconds
+    dt.time.minutes    = ((tmp[2] & 0xF0) >> 4) * 10 + (tmp[2] & 0x0F);   // Transform minutes
+    dt.time.hours      = ((tmp[3] & 0x30) >> 4) * 10 + (tmp[3] & 0x0F);   // Transform hours
+    dt.time.fmt_hours  =  (tmp[3] & 0x80);                                // 12/24 hour format
+    dt.time.am_pm_flag =  (tmp[3] & 0x40);                                // Am/Pm flag
+    dt.date.day        = ((tmp[4] & 0x30) >> 4) * 10  + (tmp[4] & 0x0F);  // Transform day
+
+    if(address == TIME)
+        year_bits = (tmp[4] & 0xC0) >> 6;
+    else
+        dt.date.year = 0;                                              // No year for alarm
+
+    dt.date.month   = ((tmp[5] & 0x10)  >> 4) * 10 + (tmp[5] & 0x0F);  // Transform month
+
+    if(address == TIME)
+        dt.date.weekday =  tmp[5] >> 5;
+    else
+        dt.date.weekday =  0;                                          // No weekday for alarm
+
+    if(address == TIME) {
+        tmp[0] = readByte(CENTURY_REG);
+        dt.date.century  = ((tmp[0] & 0xF0) >> 4) * 10 + (tmp[0] & 0x0F);
+        tmp[0] = readByte(YEAR_REG);
+        dt.date.year  = ((tmp[0] & 0xF0)  >> 4) * 10 + (tmp[0] & 0x0F);
+
+        if(year_bits > 0) {                                            // Midnight on new years eve?
+            dt.date.year += 1;                                         // Increment the year
+            writeByte(YEAR_REG, dt.date.year);                         // Save the new year value to NV Ram
+            writeByte(5, dt.date.day & 0x3F);                          // Clear the year bits but preserve the date
+        }
+    }
+};
+
+struct DateTime_t PCF8583rtc::GetDateTime(void)
+{
+  return dt;    
+}
+ 
+struct DateTime_t PCF8583rtc::GetDateTimeBCD(void)
+{
+    struct DateTime_t dtb;
+    
+    dtb = dt;
+    dtb.time.hours    = bin2bcd(dt.time.hours);
+    dtb.time.minutes  = bin2bcd(dt.time.minutes);
+    dtb.time.seconds  = bin2bcd(dt.time.seconds);
+    dtb.time.hundreds = bin2bcd(dt.time.hundreds);
+
+    dtb.date.day      = bin2bcd(dt.date.day);
+    dtb.date.month    = bin2bcd(dt.date.month);
+    dtb.date.year     = bin2bcd(dt.date.year);
+    dtb.date.century  = bin2bcd(dt.date.century);
+  
+    return dtb;
+}
+
+void PCF8583rtc::FormatDateTime(char *dest, char *f)
+{
+    if(f != 0 && *f != 0) {   //If the format param is empty then do a default 'c'
+        while(*f != 0) {        //expect null terminated string (we hope)
+            switch(*f) {
+                case 'c':
+                    break;
+                case 'd':
+                    if(*(f+1) != 'd') {            //'d' - Day with no leading zero
+                        dest += Bcd2Char(dest, dt.date.day, FALSE);
+                    } else {
+                        f++;
+                        if(*(f+1) != 'd')            //'dd' - Day with leading zero
+                            dest += Bcd2Char(dest, dt.date.day, TRUE);
+                        else {
+                            f++;
+                            if(*(f+1) != 'd') {        //'ddd' - Short day name
+//                                i = 0;
+//                                while(ShortDayNames[dt.date.weekday][i] != 0)
+//                                    *dest++ = ShortDayNames[dt.date.weekday][i++];
+                            } else {
+                                f++;
+//                                i = 0;
+//                                while(LongDayNames[dt.date.weekday][i] != 0)
+//                                    *dest++ = LongDayNames[dt.date.weekday][i++];
+                            }
+                        }
+                    }
+                    break;
+                case 'm':
+                    if(*(f+1) != 'm') {            //'m' - Month with no leading zero
+                        dest += Bcd2Char(dest, dt.date.month, FALSE);
+                    } else {
+                        f++;
+                        if(*(f+1) != 'm')            //'mm' - Month with leading zero
+                            dest += Bcd2Char(dest, dt.date.month, TRUE);
+                        else {
+                            f++;
+                            if(*(f+1) != 'm') {        //'mmm' - Short month name
+//                                i = 0;
+//                                while(ShortMonthNames[dt.date.month - 1][i] != 0)
+//                                    *dest++ = ShortMonthNames[dt.date.month - 1][i++];
+                            } else {
+                                f++;
+//                                i = 0;
+//                                while(LongMonthNames[dt.date.month - 1][i] != 0)
+//                                    *dest++ = LongMonthNames[dt.date.month - 1][i++];
+                            }
+                        }
+                    }
+                    break;
+                case 'y':
+                    if(*(f+1) == 'y') {
+                        f++;                                 //We have at least a 'yy'
+                        if(*(f+1) == 'y' && *(f+2) == 'y') { //'yyyy' - 4 digit year
+                            dest += Bcd2Char(dest, dt.date.century, TRUE);
+                            f += 2;
+                        }
+                        dest += Bcd2Char(dest, dt.date.year, TRUE);
+                    }
+                    break;
+                case 'h':
+                    if(*(f+1) != 'h') {            //'h' - Hour with no leading zero
+                        dest += Bcd2Char(dest, dt.time.hours, FALSE);
+                    } else {
+                        f++;
+                        dest += Bcd2Char(dest, dt.time.hours, TRUE);
+                    }
+                    break;
+                case 'n':
+                    if(*(f+1) != 'n') {            //'m' - Minutes with no leading zero
+                        dest += Bcd2Char(dest, dt.time.minutes, FALSE);
+                    } else {
+                        f++;
+                        dest += Bcd2Char(dest, dt.time.minutes, TRUE);
+                    }
+                    break;
+                case 's':
+                    if(*(f+1) != 's') {            //'s' - Seconds with no leading zero
+                        dest += Bcd2Char(dest, dt.time.seconds, FALSE);
+                    } else {
+                        f++;
+                        dest += Bcd2Char(dest, dt.time.seconds, TRUE);
+                    }
+                    break;
+                case 'z':
+                    if(*(f+1) != 'z') {            //'z' - Hundredths with no leading zero
+                        dest += Bcd2Char(dest, dt.time.hundreds, FALSE);
+                    } else {
+                        f++;
+                        dest += Bcd2Char(dest, dt.time.hundreds, TRUE);
+                    }
+                    break;
+                case '/':
+                    *dest++ = DateSeparator;
+                    break;
+                case ':':
+                    *dest++ = TimeSeparator;
+                    break;
+                case 39 :
+                    while(*++f != 0 && *f != 39) *dest++ = *f;
+                    break;  //Ignore the first '
+                default:
+                    *dest++ = *f;
+                    break;            //Anything we don't recognise, return it
+            }
+            f++;
+        }
+    }
+    *dest = 0;    //Null terminate
+};
+
+bool PCF8583rtc::WriteNVram(char address, char *value, char num)
+{
+    if((address < USER_REG) || (num == 0))       // dont allow overwriting first 2 user bytes
+        return false;
+    
+    _i2c->write(PCF8583_addr, &address, 1); // set the rom address
+    return _i2c->write(PCF8583_addr, value, num);  // write the data
+};
+
+bool PCF8583rtc::ReadNVram(char address, char * dest, char num)
+{
+    if((address < USER_REG) || (num == 0))       // dont allow overwriting first 2 user bytes
+        return false;
+    
+    _i2c->write(PCF8583_addr, &address, 1); // set the rom address
+    _i2c->read(PCF8583_addr, dest, num);    // read the data
+    
+    return true;
+};
+
+/*****************************************************************************/
+/************************** Private Functions ********************************/
+/*****************************************************************************/
+
+char PCF8583rtc::Bcd2Char(char *d, char val, char WantLeadZero)
+{
+    char  n = 0;
+
+    if(WantLeadZero == TRUE || (val / 10) != 0) {
+        *d++ = (val / 10) + 48;
+        n++;
+    }
+    *d = (val % 10) + 48;
+    return(n + 1);
+}
+
+//----------------------------------------------
+// This function converts an 8 bit binary value to a 2 byte BCD value.
+// The input range must be from 0 to 99.
+int PCF8583rtc::bin2bcd(char value)
+{
+    int tmp = 0;
+
+    while(1) {
+        // Get the tens digit by doing multiple subtraction
+        // of 10 from the binary value.
+        if(value >= 10) {
+            value -= 10;
+            tmp += 0x10;
+        } else {  // Get the ones digit by adding the remainder.
+            tmp += value;
+            break;
+        }
+    }
+    return tmp;
+}
+
+void PCF8583rtc::writeByte(char address, char d)
+{
+    _i2c->start();
+    _i2c->write(Write_addr);
+    _i2c->write(address);
+    _i2c->write(d);
+    _i2c->stop();
+}
+
+void PCF8583rtc::configureControlReg(char control)
+{
+    _i2c->start();
+    _i2c->write(Write_addr);
+    _i2c->write(0x00);
+    _i2c->write(control);
+    _i2c->stop();
+}
+
+void PCF8583rtc::configureAlarmReg(char alarm)
+{
+    _i2c->start();
+    _i2c->write(Write_addr);
+    _i2c->write(0x08);
+    _i2c->write(alarm);
+    _i2c->stop();
+}
+
+char PCF8583rtc::readByte(char address)
+{
+    char var;
+    _i2c->start();
+    _i2c->write(Write_addr);
+    _i2c->write(address);
+    _i2c->start();
+    _i2c->write(Read_addr);
+    var = _i2c->read(0) ;
+    _i2c->stop();
+    return var;
+}
+
+void PCF8583rtc::pauseCounting()
+{
+    char tmp;
+    tmp = readByte(0x00);
+    tmp = tmp | 0x80;
+    writeByte(0x00, tmp);
+}
+
+void PCF8583rtc::enableCounting()
+{
+    char tmp;
+    tmp = readByte(0x00);
+    tmp = tmp ^ 0x80;
+    writeByte(0x00, tmp);
+}