Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/NXP Semiconductors/LPC15xx/SYSCON/RTCOSCCTRL#0x0
EN=DISABLED_RTC_CLOCK_
RTC oscillator control
RTC 32 kHz clock enable.
0 (DISABLED_RTC_CLOCK_): Disabled. RTC clock off.
1 (ENABLED_RTC_CLOCK_O): Enabled. RTC clock on.
Reserved
https://github.com/cmsis-svd/cmsis-svd-data