Example Of Setting X1 Oscillator - Renesas RL78 Series User Manual

16-bit single-chip microcontrollers

Hide thumbs Also See for RL78 Series:

Table of Contents

RL78/F13, F14

5.6.2 Example of Setting X1 Oscillator

After a reset release, the CPU/peripheral hardware clock (f

oscillator clock. To subsequently change the clock to the X1 oscillation clock, set the oscillator and start oscillation by using

the clock operation mode control register (CMC) and clock operation status control register (CSC) and wait for oscillation to

stabilize by using the oscillation stabilization time counter status register (OSTC). After the oscillation stabilizes, set the X1

oscillation clock to f

by using the system clock control register (CKC).

[Register settings] Set the registers in the following order.

<1> Set the OSCSEL bit of the CMC register to 1, except for the cases where the frequency is equal or more than 10MHz,

in such cases set the AMPH bit to 1, to operate the X1 oscillator.

<2> Using the OSTS register, select the oscillation stabilization time of the X1 oscillator at releasing of the STOP mode.

Example: Setting values when a wait of at least 102.4

<3> Clear (0) the MSTOP bit of the CSC register to start oscillating the X1 oscillator.

<4> Use the OSTC register to wait for oscillation of the X1 oscillator to stabilize.

Example: Wait until the bits reach the following values when a wait of at least 102.4

<5> Use the MCM0 bit of the CKC register to specify the X1 oscillation clock as the CPU/peripheral hardware clock.

<6> Use the MCS bit of the CKC register to confirm that f

hardware clock (MCS = 1).

R01UH0368EJ0210 Rev.2.10

Dec 10, 2015

CHAPTER 5 CLOCK GENERATOR

) always starts operating with the high-speed on-chip

s is set based on a 10 MHz resonator.

(X1 oscillation clock) is selected as the CPU/peripheral

s is set based on a 10 MHz

Show Quick Links

Table of Contents

Rl78/f13 Rl78/f14