Application - DS1302 ,RTC module

Hardware

• In version 2 Pi GPIO27 is in place of GPIO21 (same pin)

Software

• Real Time Clock Source Code

 Modify the following GPIO definition for RPi 2
 #define GPIO_ADD 0x20200000L                          ->  #define GPIO_ADD 0x3F000000L
 #define SCLK_OUTPUT *(gpio+GPIO_SEL2) &= 0xFFFFFFC7L  ->  #define SCLK_OUTPUT *(gpio+GPIO_SEL2) &= 0xFF1FFFFFL
 #define SCLK_HIGH *(gpio+GPIO_SET) = 0x00200000L      ->  #define SCLK_HIGH *(gpio+GPIO_SET) = 0x08000000L
 #define SCLK_LOW *(gpio+GPIO_CLR) = 0x00200000L       ->  #define SCLK_LOW *(gpio+GPIO_CLR) = 0x08000000L

Reference

• Raspberry Pi Real Time Clock