M16C6K9 Datasheet, PDF (37/292 Pages) Renesas Technology Corp – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

M16C/6K9 Group
Power control
Power control
The following is a description of the power control modes:
Modes
Power control is available in three modes.
(1) Normal operation mode
• High-speed mode
Divide-by-1 frequency of the main clock becomes the BCLK. The CPU operates with the internal clock
selected. Each peripheral function operates according to its assigned clock.
• Medium-speed mode
Divide-by-2, divide-by-4, divide-by-8, or divide-by-16 frequency of the main clock becomes the BCLK. The
CPU operates according to the internal clock selected. Each peripheral function operates according to its
assigned clock.
• Low-speed mode
fC becomes the BCLK. The CPU operates according to the fc clock. The fc clock is supplied by the sub clock.
Each peripheral function operates according to its assigned clock.
• Low power consumption mode
The main clock operating in low-speed mode is stopped. The CPU operates according to the fC clock. The
fc clock is supplied by the sub clock. The only peripheral functions that operate are those with the sub-clock
selected as the count source.
(2) Wait mode
The CPU operation is stopped. The oscillators do not stop.
(3) Stop mode
All oscillators stop. The CPU and all built-in peripheral functions stop. This mode, among the three modes
listed here, is the most effective in decreasing power consumption.
Fig.WA-5 is the state transition diagram of (1) to (3).
Rev.1.00 Jun 06, 2003 page 37 of 290