R5F21257SNFP#U0 Renesas Electronics America, R5F21257SNFP#U0 Datasheet - Page 352

• 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 16.21
16.2.7
When setting the SSUMS bit in the SSMR2 register to 1 (4-wire bus communication mode) and the CSS1 bit in
the SSMR2 register to 1 (functions as SCS output pin), set the MSS bit in the SSCRH register to 1 (operates as
the master device) and check the arbitration of the SCS pin before starting serial transfer. If clock synchronous
serial I/O with chip select detects that the synchronized internal SCS signal is held “L” in this period, the CE bit
in the SSSR register is set to 1 (conflict error) and the MSS bit is automatically set to 0 (operates as a slave
device).
Figure 16.21 shows the Arbitration Check Timing.
Future transmit operations are not performed while the CE bit is set to 1. Set the CE bit to 0 (no conflict error)
before starting transmission.
(synchronization)
SSCRH register
Feb 29, 2008
Transfer start
Internal SCS
SCS Pin Control and Arbitration
SCS output
MSS bit in
SCS input
Arbitration Check Timing
CE
1
0
Page 333 of 485
High-impedance
During arbitration detection
Data write to
SSTDR register
Maximum time of SCS internal
synchronization
16. Clock Synchronous Serial Interface