HD64336900G Datasheet, PDF (120/408 Pages) Renesas Technology Corp – 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Tiny Series

6.3 Operating Frequency in Active Mode
Operation in active mode is clocked at the frequency designated by the MA2 to MA0 bits in
SYSCR2. The operating frequency changes to the set frequency after SLEEP instruction
execution.
6.4 Direct Transition
The CPU can execute programs in active mode. The operating frequency can be changed by
making a transition directly from active mode to active mode. A direct transition can be made by
executing a SLEEP instruction while the DTON bit in SYSCR2 is set to 1. If the direct transition
interrupt is disabled by the interrupt enable register 1, a transition is made instead to sleep mode or
subsleep mode. Note that if a direct transition is attempted while the I bit in condition code register
(CCR) is set to 1, sleep mode or subsleep mode will be entered though that mode cannot be
cleared by means of an interrupt.
6.5 Module Standby Function
The module standby function can be set to any peripheral module. In module standby mode, the
clock supply to the specified module stops and the module enters the power-down mode. Module
standby mode enables each on-chip peripheral module to enter the standby state by setting a bit
that corresponds to each module in MSTCR1 and MSTCR2 to 1 and cancels the mode by clearing
the bit to 0.
Rev. 1.00, 11/03, page 92 of 376