recently switch from arduino uno to mega simply because i needed the extra inputs, however realized that bods and bodse are not available on arduino mega 2560. what should i do to my codes? just remove functions which involves bods/bodse? will it affect the ability of my device to log data? codes from https://github.com/Make-Magazine/Data-Logger/blob/master/Datalogger/Datalogger.ino

Arduino: 1.6.5 (Windows 8), Board: "Arduino Mega or Mega 2560, ATmega2560 (Mega 2560)" sketch_jul01a.ino: In function 'int doSleep(long int)': sketch_jul01a:221: error: 'BODS' was not declared in this scope sketch_jul01a:221: error: 'BODSE' was not declared in this scope 'PRR' was not declared in this scope

any help is very much appreciated thank you regards