TIMEOUT=CYCLES2, MODE=XTAL
Do not write to this register unless the oscillator is forced off. The oscillator is forced off if DISONDEMAND is set and FORCEEN is cleared.
| AGC | LFXO AGC Enable |
| HIGHAMPL | LFXO High Amplitude Enable |
| MODE | LFXO Mode 0 (XTAL): A 32768Hz crystal should be connected to the LF crystal pads. Voltage must not exceed VDDIO. 1 (BUFEXTCLK): An external sine source with minimum amplitude 100mv (zero-to-peak) and maximum amplitude 500mV (zero-to-peak) should be connected in series with LFXTAL_I pin. Minimum voltage should be larger than ground and maximum voltage smaller than VDDIO. The sine source does not need to be ac coupled externally as it is ac couples inside LFXO. LFXTAL_O is free to be used as a general purpose GPIO. 2 (DIGEXTCLK): An external 32KHz CMOS clock should be provided on LFXTAL_I. LFXTAL_O is free to be used as a general purpose GPIO. |
| TIMEOUT | LFXO Start-up Delay 0 (CYCLES2): Timeout period of 2 cycles 1 (CYCLES256): Timeout period of 256 cycles 2 (CYCLES1K): Timeout period of 1024 cycles 3 (CYCLES2K): Timeout period of 2048 cycles 4 (CYCLES4K): Timeout period of 4096 cycles 5 (CYCLES8K): Timeout period of 8192 cycles 6 (CYCLES16K): Timeout period of 16384 cycles 7 (CYCLES32K): Timeout period of 32768 cycles |