r5f21346mnfp Renesas Electronics Corporation., r5f21346mnfp Datasheet - Page 735

• 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
35.1.3
35.1.4
35.1.5
35.1.6
Set the VCA20 bit to 1 in low-speed clock mode or low-speed on-chip oscillator mode before entering wait
mode.
To enter wait mode by setting the CM30 bit in the CM3 register to 1 (MCU enters wait mode), follow the
procedure shown in Figure 33.1 to set the procedure for reducing internal power consumption using the VCA20
bit.
To enter wait mode by executing WAIT instruction, follow the procedure shown in Figure 33.2 to set the
procedure for reducing internal power consumption using the VCA20 bit.
Since the oscillation stop detection function cannot be used if the XIN clock frequency is below 2 MHz, set bits
OCD1 to OCD0 to 00b. In addition, the OCD3 bit cannot be used to confirm whether the XIN clock oscillation
is stable.
Consult the oscillator manufacturer to determine the optimal oscillation circuit constants for the user system.
When the high-speed on-chip oscillator mode is selected as the system clock, do not enter stop mode while bits
CM37 and CM36 in the CM3 register is 00b (MCU exits with the CPU clock used immediately before entering
wait or stop mode).
Reducing Internal Power Using VCA20 Bit
Oscillation Stop Detection Function
Oscillation Circuit Constants
High-Speed On-chip Oscillator Mode
35. Usage Notes
Page 703 of 740