R5F21356CNFP#U0 Renesas Electronics America, R5F21356CNFP#U0 Datasheet - Page 166

• Manufacturer Part Number: R5F21356CNFP#U0
• Description: MCU 1KB FLASH 32K ROM 52-LQFP
• Manufacturer: Renesas Electronics America
• Series: R8C/3x/35Cr

Specifications of R5F21356CNFP#U0

• Core Processor: R8C
• Core Size: 16/32-Bit
• Speed: 20MHz
• Connectivity: I²C, LIN, SIO, SSU, UART/USART
• Peripherals: POR, PWM, Voltage Detect, WDT
• Number Of I /o: 47
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Ram Size: 2.5K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 12x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 85°C
• Package / Case: 52-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

R8C/35C Group
REJ09B0567-0100 Rev.1.00 Dec. 14, 2009
Page 133 of 725
9.6
9.6.1
9.6.2
9.6.3
9.6.4
9.6.5
9.6.6
There are a CPU clock to operate the CPU and a peripheral function clock to operate the peripheral functions. Refer
to Figure 9.1 Clock Generation Circuit.
The system clock is the clock source for the CPU and peripheral function clocks. The XIN clock, the XCIN
clock, or the on-chip oscillator clock can be selected.
The CPU clock is an operating clock for the CPU and the watchdog timer.
The system clock divided by 1 (no division), 2, 4, 8, or 16 is used as the CPU clock. Use the CM06 bit in the
CM0 register and bits CM16 and CM17 in the CM1 register to select the value of the division.
Also, use the XCIN clock while the XCIN clock oscillation stabilizes.
After a reset, the low-speed on-chip oscillator clock divided by 1 (no division) is used as the CPU clock.
When the MCU enters stop mode, the CM06 bit is set to 1 (divide-by-8 mode). To enter stop mode, set the
CM35 bit in the CM3 register to 0 (settings of CM06 in CM0 register and bits CM16 and CM17 in CM1
register enabled).
The peripheral function clock is an operating clock for the peripheral functions.
The fi (i = 1, 2, 4, 8, and 32) clock is generated by the system clock divided by i. It is used for timers RA, RB,
RC, RD, RE, the serial interface, and the A/D converter.
If the MCU enters wait mode after the CM02 bit in the CM0 register is set to 1 (peripheral function clock stops
in wait mode), the fi clock stops.
fOCO is an operating clock for the peripheral functions.
This clock runs at the same frequency as the on-chip oscillator clock and can be used as the source for timer
RA.
In wait mode, the fOCO clock does not stop.
fOCO40M is used as the count source for timers RC and RD.
This clock is generated by the high-speed on-chip oscillator and supplied by setting the FRA00 bit to 1.
In wait mode, the fOCO40M clock does not stop.
This clock can be used with supply voltage VCC = 2.7 to 5.5 V.
fOCO-F is used as the count source for timers RC, RD and the A/D converter.
fOCO-F is a clock generated by the high-speed on-chip oscillator and divided by i (i = 2, 3, 4, 5, 6, 7, 8, and 9;
divide ratio selected by the FRA2 register). This clock is supplied by setting the FRA00 bit to 1.
In wait mode, the fOCO-F clock does not stop.
CPU Clock and Peripheral Function Clock
System Clock
CPU Clock
Peripheral Function Clock (f1, f2, f4, f8, and f32)
fOCO
fOCO40M
fOCO-F
9. Clock Generation Circuit