Renesas Single-Chip Microcomputer M34519T-MCU - Manual (Page 25)

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4.2 Watchdog Timer
The M34519T-MCU does not have an operational watchdog timer. Therefore, use an evaluation
MCU (OTP version) to verify the operation associated with a watchdog timer.
The M34519T-MCU outputs a signal whose waveform is shown below from check pin TP5 during
WRST instruction execution cycles. This signal allows you to check the initialization cycle of a
watchdog timer.
System clock
XIN
CNVSS
WRST
Figure 4.1 Waveform output from check pin TP5
Chapter 4. Precautions to Be Taken for Debugging a Program
4.1 Reset
The M34519T-MCU uses a 74HC14 for its RESET signal input buffer, so that its electrical
characteristics differ from those of an actual MCU. Table 4.1 lists the RESET signal input
characteristics of the M34519T-MCU.
Table 4.1 RESET signal input characteristics
H-level threshold voltage
L-level threshold voltage
Hysteresis voltage
Item Symbol
VP
VN
VH
Voltage
VCC = 2.0 V
VCC = 4.5 V
VCC = 6.0 V
VCC = 2.0 V
VCC = 4.5 V
VCC = 6.0 V
VCC = 2.0 V
VCC = 4.5 V
VCC = 6.0 V
Max.
1.5 V
3.15 V
4.2 V
0.9 V
2.0 V
2.6 V
1.0 V
1.4 V
1.7 V
Min.
1.0 V
2.3 V
3.0 V
0.3 V
1.13 V
1.5 V
0.3 V
0.6 V
0.8 V