R5F21244SNFP#U0 Renesas Electronics America, R5F21244SNFP#U0 Datasheet - Page 111

• Manufacturer Part Number: R5F21244SNFP#U0
• Description: IC R8C MCU FLASH 16K 52LQFP
• Manufacturer: Renesas Electronics America
• Series: M16C™ M16C/R8C/Tiny/24r

Specifications of R5F21244SNFP#U0

• Core Processor: R8C
• Core Size: 16-Bit
• Speed: 20MHz
• Connectivity: I²C, LIN, SIO, SSU, UART/USART
• Peripherals: POR, Voltage Detect, WDT
• Number Of I /o: 41
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: FLASH
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.2 V ~ 5.5 V
• Data Converters: A/D 12x10b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 85°C
• Package / Case: 52-LQFP
• For Use With: R0K521256S000BE - KIT EVAL STARTER FOR R8C/25
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

R8C/24 Group, R8C/25 Group
Rev.3.00
REJ09B0244-0300
Figure 10.13
Step (1)
Step (2)
Step (3)
Step (4)
Step (5)
Step (6)
Step (7)
Step (8)
NOTES:
10.5.2.5
1. Execute this routine to handle all interrupts generated in wait mode.
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 entering wait mode, follow 10.7.2 Wait Mode.
VCA20: Bit in VCA2 register
However, this does not apply if it is not necessary to start the high-speed clock or high-speed on-chip oscillator during the interrupt
routine.
Internal power consumption can be reduced by using low-speed clock mode or low-speed on-chip oscillator
mode. Figure 10.13 shows the Procedure for Enabling Reduced Internal Power Consumption Using VCA20 bit.
When enabling reduced internal power consumption using the VCA20 bit, follow Figure 10.13 Procedure for
Enabling Reduced Internal Power Consumption Using VCA20 bit.
VCA20 ← 1 (internal power low consumption
VCA20 ← 0 (internal power low consumption
Enter low-speed clock mode or low-speed
(Wait until XIN clock oscillation stabilizes)
Feb 29, 2008
low consumption enabled by VCA20 bit
Stop XIN clock and high-speed on-chip
Start XIN clock or high-speed on-chip
Handling procedure of internal power
high-speed on-chip oscillator mode
Enter high-speed clock mode or
on-chip oscillator mode
Reducing Internal Power Consumption
Procedure for Enabling Reduced Internal Power Consumption Using VCA20 bit
Enter wait mode
oscillator clock
oscillator clock
enabled)
disabled)
(2, 3)
(2)
Page 92 of 485
(4)
Exit wait mode by interrupt
Step (5)
Step (6)
Step (7)
Step (8)
Step (1)
Step (2)
Step (3)
VCA20 ← 0 (internal power low consumption
VCA20 ← 1 (internal power low consumption
(Wait until XIN clock oscillation stabilizes)
Stop XIN clock and high-speed on-chip
Start XIN clock or high-speed on-chip
high-speed on-chip oscillator mode
low-speed on-chip oscillator mode
Enter high-speed clock mode or
Enter low-speed clock mode or
Interrupt handling completed
In interrupt routine
Interrupt handling
oscillator clock
oscillator clock
enabled)
disabled)
(2, 3)
(2)
(Note 1)
10. Clock Generation Circuit
If it is necessary to start
the high-speed clock or
the high-speed on-chip
oscillator in the interrupt
routine, execute steps (5)
to (7) in the interrupt
routine.
If the high-speed clock or
high-speed on-chip
oscillator is started in the
interrupt routine, execute
steps (1) to (3) at the last of
the interrupt routine.