DF71251AD50FPV Renesas Electronics America, DF71251AD50FPV Datasheet - Page 431

• 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: -

11.4.3
When operating in interval timer mode, interval timer interrupts are generated at every overflow of
the counter. This enables interrupts to be generated at set periods.
1. Clear the WT/IT bit in WTCSR to 0, set the type of count clock in the CKS2 to CKS0 bits, and
2. Set the TME bit in WTCSR to 1 to start the count in interval timer mode.
3. When the counter overflows, the WDT sets the IOVF flag in WTCSR to 1 and an interval
set the initial value of the counter in the WTCNT counter.
timer interrupt request is sent to the INTC. The counter then resumes counting.
WDTOVF signal
Internal reset signal
(power-on reset selected)
Internal reset signal
(manual reset selected)
Using Interval Timer Mode
(When WTCNT Count Clock is Specified to Pφ/32 by CKS2 to CKS0)
WTCNT value
H'FF
H'00
Figure 11.3 Operation in Watchdog Timer Mode
WT/IT = 1
TME = 1
H'00 is written
to WTCNT
WDTOVF is asserted and
an internal reset is generated
Overflow occurs
3 Pφ + one cycle of count clock
WOVF = 1
32 Pφ clock
Rev. 5.00 Mar. 06, 2009 Page 411 of 770
18 Pφ clock
Count starts
H'00 is written
to WTCNT
REJ09B0243-0500
Time