How-To Guide

Table Of Contents
R01UH0823EJ0110 Rev.1.10 Page 848 of 1852
Nov 30, 2020
RX23W Group 31. Independent Watchdog Timer (IWDTa)
31.2.3 IWDT Status Register (IWDTSR)
Note 1. Only 0 can be written to clear the flag.
The IWDTSR register is initialized by the reset source of the IWDT. The IWDTSR register is not initialized by other
reset sources.
CNTVAL[13:0] Bits (Counter Value)
These bits are used to confirm the counter value of the counter, but note that the read value may differ from the actual
count by a value of one count.
UNDFF Flag (Underflow Flag)
This bit is used to confirm whether or not an underflow has occurred in the counter.
The value 1 indicates that the counter has underflowed. The value 0 indicates that the counter has not underflowed.
Write 0 to the UNDFF flag to set the value to 0. Writing 1 has no effect.
REFEF Flag (Refresh Error Flag)
This bit is used to confirm whether or not a refresh error (performing a refresh operation during a refresh-prohibited
period).
The value 1 indicates that a refresh error has occurred. The value 0 indicates that no refresh error has occurred.
Write 0 to the REFEF flag to set the value to 0. Writing 1 has no effect.
Address(es): IWDT.IWDTSR 0008 8034h
b15 b14 b13 b12 b11 b10 b9 b8 b7 b6 b5 b4 b3 b2 b1 b0
REFEF UNDFF CNTVAL[13:0]
Value after reset:
0000000000000000
Bit Symbol Bit Name Description R/W
b13 to b0 CNTVAL[13:0] Counter Value Value counted by the counter R
b14 UNDFF Underflow Flag 0: No underflow occurred
1: Underflow occurred
R/(W)
*
1
b15 REFEF Refresh Error Flag 0: No refresh error occurred
1: Refresh error occurred
R/(W)
*
1