I have the LPC Xpresso 11U68 demo board and I'm trying to get the RTC alarm to work. I can change the COUNT register and it is properly incrementing. The RTC status is 0x90 and the MATCH register is 0xffffffff. If I call Chip_RTC_SetAlarm(LPC_RTC, value) then read back the MATCH register it is unchanged from 0xffffffff.
Is there anything special I need to do in order to change the alarm?