DF2398TE20 Renesas Electronics America, DF2398TE20 Datasheet - Page 490

• Manufacturer Part Number: DF2398TE20
• Description: IC H8S MCU FLASH 256K 120TQFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8S/2300r

Specifications of DF2398TE20

• Core Processor: H8S/2000
• Core Size: 16-Bit
• Speed: 20MHz
• Connectivity: SCI, SmartCard
• Peripherals: DMA, POR, PWM, WDT
• Number Of I /o: 87
• Program Memory Size: 256KB (256K x 8)
• Program Memory Type: FLASH
• Ram Size: 8K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 8x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 120-TQFP, 120-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Other names: HD64F2398TE20; HD64F2398TE20

13.3
13.3.1
To use the WDT as a watchdog timer, set the WT/IT and TME bits to 1. Software must prevent TCNT overflows by
rewriting the TCNT value (normally be writing H'00) before overflows occurs. This ensures that TCNT does not overflow
while the system is operating normally. If TCNT overflows without being rewritten because of a system crash or other
error, the WDTOVF signal*
system. The WDTOVF signal*
If TCNT overflows when 1 is set in the RSTE bit in RSTCSR, a signal that resets the H8S/2357 Group internally is
generated at the same time as the WDTOVF signal*
depending on the setting of the RSTS bit in RSTCSR. The internal reset signal is output for 518 states.
If a reset caused by a signal input to the RES pin occurs at the same time as a reset caused by a WDT overflow, the RES
pin reset has priority and the WOVF bit in RSTCSR is cleared to 0.
Notes: 1. In the F-ZTAT version, the H8S/2398, H8S/2394, H8S/2392, or H8S/2390, the WDTOVF pin function is not
Rev.6.00 Oct.28.2004 page 460 of 1016
REJ09B0138-0600H
2. Manual reset is only supported in the H8S/2357 ZTAT.
Operation
Watchdog Timer Operation
available.
Legend:
WT/IT:
TME:
Notes: 1. The internal reset signal is generated only if the RSTE bit is set to 1.
Internal reset signal *
WDTOVF signal *
2. 130 states when the RSTE bit is cleared to 0.
3. The WDTOVF pin function is not available in the F-ZTAT version, the H8S/2398, H8S/2394,
Timer mode select bit
Timer enable bit
1
is output. This is shown in figure 13-4. This WDTOVF signal*
H8S/2392, or H8S/2390.
1
H'FF
H'00
is output for 132 states when RSTE = 1, and for 130 states when RSTE = 0.
TCNT count
3
WT/IT=1
TME=1
1
Figure 13-4 Watchdog Timer Operation
H'00 written
to TCNT
1
. This reset can be selected as a power-on reset or a manual reset*
WDTOVF *
internal reset are
generated
Overflow
WOVF=1
132 states *
518 states
3
and
2
WT/IT=1
TME=1
H'00 written
to TCNT
1
can be used to reset the
Time
2
,