r5f21346mnfp Renesas Electronics Corporation., r5f21346mnfp Datasheet - Page 702

• Manufacturer Part Number: r5f21346mnfp
• Description: Single-chip Mcus Incorporates The R8c Cpu Core
• Manufacturer: Renesas Electronics Corporation.

R8C/34M Group
R01UH0131EJ0100 Rev.1.00
Jun 21, 2011
Figure 33.1
33.2.9
Notes:
1. After entering wait mode by the CM30 bit, when an interrupt request is generated, without performing interrupt handling,
2. Do not set the VCA20 bit to 0 with the instruction immediately after setting the VCA20 bit to 1. Also, do not do the opposite.
3. When the VCA20 bit is set to 1, do not set the CM10 bit to 1 (stop mode).
4. When the MCU enters wait mode, follow 9.7.2 Wait Mode.
The electric current in wait mode can be further reduced by setting the VCA20 bit in the VCA2 register to 1
(low consumption enabled). Set the VCA20 bit to 1 in low-speed clock mode or low-speed on-chip oscillator
mode before entering wait mode.
The setting procedure for reducing internal power consumption using the VCA20 bit differs when the CM30 bit
in the CM3 register is set to 1 (MCU enters wait mode) to enter wait mode and when the WAIT instruction is
executed to enter wait mode. Figure 33.1 shows the Setting Procedure for Reducing Internal Power
Consumption Using VCA20 Bit when CM30 Bit in CM3 Register is Set to 1 (MCU Enters Wait Mode) to Enter
Wait Mode. Figure 33.2 shows the Setting Procedure for Reducing Internal Power Consumption Using VCA20
Bit when WAIT Instruction is Executed to Enter Wait Mode.
start the execution from the instruction immediately following the instruction to set the CM30 bit to 1.
Reducing Internal Power Consumption Using VCA20 Bit
CM30 Bit in CM3 Register is Set to 1 (MCU Enters Wait Mode) to Enter Wait Mode
Setting Procedure for Reducing Internal Power Consumption Using VCA20 Bit when
Step (1)
Step (2)
Step (3)
Step (4)
Step (5)
Step (6)
Step (7)
Step (8)
Procedure for enabling reduced internal power
(internal power low consumption enabled)
(internal power low consumption disabled)
(Wait until XIN clock or high-speed on-chip
oscillator clock oscillation stabilizes)
high-speed on-chip oscillator mode
high-speed on-chip oscillator clock
Enter wait mode using CM30 bit
high-speed on-chip oscillator clock
low-speed on-chip oscillator mode
Enter high-speed clock mode or
Enter low-speed clock mode or
consumption using VCA20 bit
Stop XIN clock and
Start XIN clock or
VCA20 ← 1
VCA20 ← 0
(4)
(2, 3)
(2)
Exit wait mode by interrupt request
33. Reducing Power Consumption
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