HD6473032F16 Datasheet, PDF (645/847 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

Section 19 Clock Pulse Generator
19.5.3 Usage Notes
The DIVCR setting changes the φ frequency, so note the following points.
• Select a frequency division ratio that stays within the assured operation range specified for the
clock cycle time t_cyc in the AC electrical characteristics. Note that φ_MIN = 2 MHz. Avoid
settings that give system clock frequencies less than 2 MHz.
• All on-chip module operations are based on φ. Note that the timing of timer operations, serial
communication, and other time-dependent processing differs before and after any change in
the division ratio. The waiting time for exit from software standby mode also changes when
the division ratio is changed. For details, see section 20.4.3, Selection of Waiting Time for Exit
from Software Standby Mode.
Rev. 3.00 Mar 21, 2006 page 615 of 814
REJ09B0302-0300