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4 watchdog timer, 5 pullup transistor control – Renesas MCU Board for 4513/4514 Group MCUs M34514T-MCU User Manual

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Figure 5.1 Waveform output from check pin TP5

5.5 Pullup Transistor Control

Since ports P

0

and P

1

contain emulation circuits, you can not control the pullup resistors using the

pullup control register PU0. If you want to use the internal pullup resistors, turn on switches SW4 to
SW7 to activate the pullup resistors on the M34514T-MCU board.

The port's resistance value of the pullup resistor (RA1) is 68 k

Ω.

5.4 Watchdog Timer

The M34514T-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 M34514T-MCU outputs a signal whose waveform is shown below from the check pin TP5
during WRST instruction execution cycles. This signal allows you to check the initialization cycle
of a watchdog timer.

WRST instruction

Next WRST instruction

System clock

X

IN

WRST