DF71251AD50FPV Renesas Electronics America, DF71251AD50FPV Datasheet - Page 427

• Manufacturer Part Number: DF71251AD50FPV
• Description: MCU RISC FLASH 32K 8K 64LQFP
• Manufacturer: Renesas Electronics America
• Series: SuperH® SH Tinyr

Specifications of DF71251AD50FPV

• Core Processor: SH-2
• Core Size: 32-Bit
• Speed: 50MHz
• Connectivity: SCI
• Peripherals: POR, PWM, WDT
• Number Of I /o: 37
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Ram Size: 8K x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

11.3.2
WTCSR is an 8-bit readable/writable register composed of bits to select the clock used for the
count, bits to select the timer mode, and overflow flags. WTCSR holds its value in an internal
reset due to the WDT overflow. WTCSR is initialized to H'00 only by a power-on reset using the
RES pin.
When used to count the clock settling time for canceling a software standby, it retains its value
after counter overflow. Use a word access to write to WTCSR, with H'A5 in the upper byte. Use a
byte access to read WTCSR.
Note: WTCSR differs from other registers in that it is more difficult to write to. See section
Bit
7
6
11.3.3, Notes on Register Access, for details.
Bit Name
TME
WT/IT
Watchdog Timer Control/Status Register (WTCSR)
Initial value:
Initial
Value
0
0
R/W:
Bit:
TME
R/W
R/W
R/W
R/W
7
0
WT/IT
R/W
6
0
Description
Timer Enable
Starts and stops timer operation. Clear this bit to 0 when
using the WDT to revoke software standby mode
0: Timer disabled: Count-up stops and WTCNT value is
1: Timer enabled
Timer Mode Select
Selects whether to use the WDT as a watchdog timer or
an interval timer.
0: Interval timer mode
1: Watchdog timer mode
Note: If WT/IT is modified when the WDT is operating,
RSTS WOVF
R/W
retained
5
0
the up-count may not be performed correctly.
R/W
4
0
IOVF
R/W
3
0
R/W
Rev. 5.00 Mar. 06, 2009 Page 407 of 770
2
0
CKS[2:0]
R/W
1
0
R/W
0
0
REJ09B0243-0500