SWCU193A April 2023 – August 2024 CC2340R2 , CC2340R5 , CC2340R5-Q1
The RTC is a 67-bit, 2-channel timer running on the LFCLK system clock. The RTC is active in the standby and active power states. When the device enters the reset or shutdown state the RTC is reset.
The RTC accumulates time elapsed since reset on each LFCLK. The RTC counter is incremented by LFINC at a rate of 32.768kHz. LFINC indicates the period of LFCLK in μs, with an additional granularity of 16 fractional bits.
The counter can be read from two 32-bit registers. RTC.TIME8U has a range of approximately 9.5 hours with an LSB representing 8 microseconds. RTC.TIME524M has a range of approximately 71.4 years with an LSB representing 524 milliseconds.
There is hardware synchronization between the system timer (SYSTIM) and the RTC so that the multi-channel and higher resolution SYSTIM remains in synchronization with the RTC’s time base.
The RTC has two channels: one compare channel and one capture channel and is capable of waking the device out of the standby power state. The RTC compare channel is typically used only by system software and only during the standby power state.