R5F21257SNFP#U0 Renesas Electronics America, R5F21257SNFP#U0 Datasheet - Page 116

• Manufacturer Part Number: R5F21257SNFP#U0
• Description: IC R8C/25 MCU FLASH 52LQFP
• Manufacturer: Renesas Electronics America
• Series: R8C/2x/25r

Specifications of R5F21257SNFP#U0

• Core Processor: R8C
• Core Size: 16/32-Bit
• Speed: 20MHz
• Connectivity: I²C, LIN, SIO, SSU, UART/USART
• Peripherals: POR, Voltage Detect, WDT
• Number Of I /o: 41
• Program Memory Size: 48KB (48K x 8)
• Program Memory Type: FLASH
• Ram Size: 2.5K 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 10.16
Table 10.6
Oscillation stop detection
((a) or (b))
Watchdog timer
Voltage monitor 1
Voltage monitor 2
Generated Interrupt Source
Feb 29, 2008
Voltage Monitor 1, and Voltage Monitor 2 Interrupts
Procedure for Switching Clock Source from Low-Speed On-Chip Oscillator to XIN
Clock
Determining Interrupt Source for Oscillation Stop Detection, Watchdog Timer,
Page 97 of 485
NO
(a) OCD3 bit in OCD register = 1
(b) OCD1 to OCD0 bits in OCD register = 11b and OCD2 bit = 1
VW2C3 bit in VW2C register = 1
VW1C2 bit in VW1C register = 1
VW2C2 bit in VW2C register = 1
Set OCD1 to OCD0 bits to 00b
that OCD3 bit is set to 0 (XIN
Multiple confirmations
Switch to XIN clock
clock oscillates) ?
Set OCD2 bit to 0
(select XIN clock)
End
YES
Bit Showing Interrupt Cause
OCD3 to OCD0: Bits in OCD register
10. Clock Generation Circuit