PCF2127 and PCF2129 are high accuracy real-time-clock (RTC) module. This library provides simple interface to accessing clock information.

Dependents:   PCF2127_Demo PCF2127_Hello

PCF2127 and PCF2129

PCF2127T PCF2127T is in SO16 package

The PCF2127 and the PCF2129 are a CMOS Real Time Clock (RTC) and calendar with an integrated Temperature Compensated Crystal (Xtal) Oscillator (TCXO) and a 32.768 kHz quartz crystal optimized for very high accuracy and very low power consumption.
Both of PCF2127 and PCF2129 have a selectable I2C-bus or SPI-bus, a backup battery switch-over circuit, a programmable watchdog function, a timestamp function, and many other features.
On addition to this, the PCF2127 has 512 bytes of general-purpose static RAM.

These 4 types of RTC modules are software compatible. So this library "PCF2127" can be used all of those.
This library only supports I2C to communicate with the PCF2127/PCF2129.

Type variations

Main feature difference

type+/-3ppm accuracy range512 bytes RAMpackage
PCF2127T-30℃ to +80℃yesSO16
PCF2127AT-30℃ to +60℃yesSO20
PCF2129T-30℃ to +80℃not availableSO16
PCF2129AT-15℃ to +60℃not availableSO20

Pin assign

/media/uploads/nxp_ip/pcf2127_pcf2129_pin_assign.png

PCF2127T
PCF2127T

Connection between MCU and PCF2127/PCF2129

These examples show how the RTC module can be connected via I2C bus.

http://developer.mbed.org/media/components/pinouts/both_types_connection3.png

References

Revision:
3:e2a6ac61fcbd
Parent:
2:db76c68f998f
--- a/PCF2127.h	Wed Dec 10 01:43:30 2014 +0000
+++ b/PCF2127.h	Wed Dec 10 02:07:35 2014 +0000
@@ -2,7 +2,7 @@
  *  PCF2127 library
  *
  *  @author     Akifumi (Tedd) OKANO, NXP Semiconductors
- *  @version    1.7
+ *  @version    1.8
  *  @date       10-Dec-2014
  *
  *  PCF2127 is a "real time clock (RTC)" module which is including a Xtal and TCXO
@@ -20,6 +20,39 @@
 
 #include    "mbed.h"
 
+/** PCF2127 class
+ *
+ *  This is a driver code for the PPCF2127: "real time clock (RTC)" module which is including a Xtal and TCXO
+ *  This class provides interface for PCF2127 operation and accessing its registers.
+ *  Detail information is available on next URL.
+ *    http://www.nxp.com/products/interface_and_connectivity/real_time_clocks/rtcs_with_temp_compensation/series/PCF2127.html
+ *
+ *  Example:
+ *  @code
+ *  #include "mbed.h"
+ *  #include "PCF2127.h"
+ *  
+ *  PCF2127 rtc( p28, p27 );
+ *  
+ *  int main()
+ *  {
+ *      time_t  t;
+ *      
+ *      printf( "PCF2127 demo started.\r\n" );
+ *  
+ *      if ( rtc.is_init_required() ) {
+ *          rtc.set_time( "2014 12 10 12 00 00" );
+ *      }
+ *  
+ *      while ( 1 ) {
+ *          t   = rtc.time( NULL );
+ *          printf( "%s\r", ctime( &t ) );
+ *          wait( 0.25 );
+ *      }
+ *  }
+ *  @endcode
+ */
+
 class PCF2127
 {
 public: