C8051F388-B Datasheet, PDF (136/285 Pages) Silicon Laboratories – Flash MCU Family

C8051F388/9/A/B
19. Oscillators and Clock Selection
C8051F388/9/A/B devices include a programmable internal high-frequency oscillator, a programmable
internal low-frequency oscillator, and an external oscillator drive circuit. The internal high-frequency oscilla-
tor can be enabled/disabled and calibrated using the OSCICN and OSCICL registers, as shown in
Figure 19.1. The internal low-frequency oscillator can be enabled/disabled and calibrated using the
OSCLCN register. The system clock can be sourced by the external oscillator circuit or either internal oscil-
lator. Both internal oscillators offer a selectable post-scaling feature.
Figure 19.1. Oscillator Options
136
Rev. 1.1