R5F21238DFP#U0 Renesas Electronics America, R5F21238DFP#U0 Datasheet - Page 452

• Manufacturer Part Number: R5F21238DFP#U0
• Description: IC R8C/23 MCU FLASH 48-LQFP
• Manufacturer: Renesas Electronics America
• Series: R8C/2x/23r

Specifications of R5F21238DFP#U0

• Core Size: 16/32-Bit
• Program Memory Size: 64KB (64K x 8)
• Peripherals: POR, Voltage Detect, WDT
• Core Processor: R8C
• Speed: 20MHz
• Connectivity: CAN, I²C, LIN, SIO, SSU, UART/USART
• Number Of I /o: 41
• Program Memory Type: FLASH
• Ram Size: 3K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 12x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 48-LQFP
• No. Of I/o's: 41
• Ram Memory Size: 3KB
• Cpu Speed: 20MHz
• No. Of Timers: 4
• Digital Ic Case Style: LQFP
• Embedded Interface Type: CAN, I2C, UART
• Rohs Compliant: Yes
• Cpu Family: R8C
• Device Core Size: 16b
• Frequency (max): 20MHz
• Interface Type: I2C/UART
• Total Internal Ram Size: 3KB
• # I/os (max): 41
• Number Of Timers - General Purpose: 5
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 3V
• On-chip Adc: 12-chx10-bit
• Instruction Set Architecture: CISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 48
• Package Type: LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: RCDK8C - KIT DEV EVAL FOR CAN R8C/23R0K521237S000BE - KIT DEV RSK R8C/23R0E521237CPE00 - EMULATOR COMPACT R8C/20/21/22/23
• Eeprom Size: -
• Lead Free Status / Rohs Status: Compliant

R8C/22 Group, R8C/23 Group
Rev.2.00 Aug 20, 2008
REJ09B0251-0200
Figure 20.11
NOTES:
Jump to the high-speed on-chip oscillator mode, low-
speed on-chip oscillator mode (XIN clock stops) program
which has been transferred to the RAM.
(The subsequent processing is executed by a program in
the RAM.)
Transfer a high-speed on-chip oscillator mode, low-
speed on-chip oscillator mode (XIN clock stops)
program to the RAM
1. Set the FMR01 bit to 1 (CPU rewrite mode enabled) before setting the FMSTP bit to 1 .
2. Before the clock source for CPU clock can be changed, the clock to which to be changed must be stable.
3. Insert a 30 µ s wait time in a program. Do not access to the flash memory during this wait time.
Low-Speed On-Chip Oscillator Mode (XIN Clock Stops) and Low-Speed Clock Mode
(XIN Clock Stops)
Process to Reduce Power Consumption in High-Speed On-Chip Oscillator Mode,
Page 430 of 501
High-speed on-chip oscillator
mode, low-speed on-chip
oscillator mode (XIN clock stops)
program
Jump to a specified address in the flash memory
Turn XIN clock on → wait until oscillation
stabilizes → switch the clock source for CPU
clock
Switch the clock source for the CPU clock.
Turn XIN off
Wait until the flash memory circuit stabilizes
(30 µ s)
Write 1 to the FMSTP bit (Flash memory stops.
Process in high-speed on-chip oscillator
mode, low-speed on-chip oscillator mode
(XIN clock stops)
Write 0 to the FMR01 bit before writing
(2)
(3)
Low power consumption state)
(CPU rewrite mode enabled)
(CPU rewrite mode disabled)
(flash memory operation)
Write
Write 0 to the FMSTP bit
0
to the FMR01 bit
20. Flash Memory
(1)
1