anning865

The error will almost certainly be on line 107. Recall that TI's headers define single-character macros that inconveniently interfere with variable declarations:

/************************************************************ * STATUS REGISTER BITS ************************************************************/ #define C (0x0001) #define Z (0x0002) #define N (0x0004) #define V (0x0100) As a general rule, don't use fully capitalized symbols for variable names, and particularly not single-letter ones.

Look in wiring.c (in energia - hardware\msp430\cores\msp430 ) to be sure you don't reprogram one of the timers that 
Energia uses internally.  (Might also want to check Tone.cpp TimerSerial.cpp and Servo library - to be sure you don't use
a timer that already used).
 
http://webcache.googleusercontent.com/search?q=cache:http://coder-tronics.com/msp430-timer-pwm-tutorial/
 
http://www.embeddedrelated.com/showarticle/182.php
 
http://homepages.ius.edu/RWISMAN/C335/HTML/msp430Timer.HTM

As a side note, check out this library I wrote - https://github.com/spirilis/RTC_B
This implements an interface to the RTC_B peripheral (Real Time Clock) present on the FR5969 chip.  It has a feature for periodic interruption, called rtc.attachPeriodicInterrupt()
 
If you use the library to actually *set* the time, you can also make use of the alarm - rtc.attachScheduledInterrupt()
 
Implementing Timer ISRs is generally frowned upon in Energia because Energia claims them for PWM, but the FR5969 has a Timer_A instance# 2 and 3 which are not used for PWM at all, and they can be commandeered for your own purposes.