DF61657CN35FTV Renesas Electronics America, DF61657CN35FTV Datasheet - Page 574

• Manufacturer Part Number: DF61657CN35FTV
• Description: IC H8SX/1657 MCU FLASH 120TQFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8SX/1600r

Specifications of DF61657CN35FTV

• Core Processor: H8SX
• Core Size: 32-Bit
• Speed: 35MHz
• Connectivity: SCI, SmartCard
• Peripherals: DMA, PWM, WDT
• Number Of I /o: 82
• Program Memory Size: 768KB (768K x 8)
• Program Memory Type: FLASH
• Ram Size: 24K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 8x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 120-TQFP, 120-VQFP
• For Use With: 3DK1657 - DEV EVAL KIT FOR H8SX/1657
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

Section 13 Watchdog Timer (WDT)
13.6.3
If bits CKS2 to CKS0 in TCSR are written to while the WDT is operating, errors could occur in
the incrementation. The watchdog timer must be stopped (by clearing the TME bit to 0) before the
values of bits CKS2 to CKS0 are changed.
13.6.4
If the timer mode is switched from watchdog timer mode to interval timer mode while the WDT is
operating, errors could occur in the incrementation. The watchdog timer must be stopped (by
clearing the TME bit to 0) before switching the timer mode.
13.6.5
This LSI is not reset internally if TCNT overflows while the RSTE bit is cleared to 0 during
watchdog timer mode operation, but TCNT and TCSR of the WDT are reset.
TCNT, TCSR, and RSTCR cannot be written to while the WDTOVF signal is low. Also note that
a read of the WOVF flag is not recognized during this period. To clear the WOVF flag, therefore,
read TCSR after the WDTOVF signal goes high, then write 0 to the WOVF flag.
13.6.6
If the WDTOVF signal is input to the RES pin, this LSI will not be initialized correctly. Make
sure that the WDTOVF signal is not input logically to the RES pin. To reset the entire system by
means of the WDTOVF signal, use a circuit like that shown in figure 13.6.
Rev. 2.00 Jun. 28, 2007 Page 548 of 864
REJ09B0341-0200
Changing Values of Bits CKS2 to CKS0
Switching between Watchdog Timer Mode and Interval Timer Mode
Internal Reset in Watchdog Timer Mode
System Reset by WDTOVF Signal
Figure 13.6 Circuit for System Reset by WDTOVF Signal (Example)
Reset signal to entire system
Reset input
WDTOVF
RES
This LSI