I'm trying to generate a 15 minutes alarm using RTC in MSP430F5438A microcontroller from Texas Instruments. What values should I put in the Interrupt registers. I have tried putting 0x95 in RTCAMIN register but it generates an interrupt at 15 min, 1 hour 15 minutes, 2 hours 15 minutes, and so on. I want the interrupt at 15 min and only one time.
You're getting the interrupt at 15 minutes already using 0x95 (meaning you are using the BCD format instead of hex, I presume). So you just want to disable the additional alarms at 1:15, 2:15, etc.
Set RTCAMIN to 0x00 as the first thing in your Interrupt Service Routine for the alarm to clear the alarm enable (AE) bit and thus set it up as a simple one-shot.