How-To Guide

Table Of Contents
R01UH0823EJ0110 Rev.1.10 Page 845 of 1852
Nov 30, 2020
RX23W Group 31. Independent Watchdog Timer (IWDTa)
31.2.2 IWDT Control Register (IWDTCR)
There are some restrictions on writing to the IWDTCR register. For details, refer to section 31.3.2, Control over
Writing to the IWDTCR, IWDTRCR, and IWDTCSTPR Registers
.
In auto-start mode, the settings in the IWDTCR register are disabled, and the settings in option function select register 0
(OFS0) are enabled. The bit setting made to the IWDTCR register can also be made in the OFS0 register. For details,
refer to
section 31.3.8, Correspondence between Option Function Select Register 0 (OFS0) and IWDT
Registers
.
Address(es): IWDT.IWDTCR 0008 8032h
b15 b14 b13 b12 b11 b10 b9 b8 b7 b6 b5 b4 b3 b2 b1 b0
RPSS[1:0] RPES[1:0] CKS[3:0] TOPS[1:0]
Value after reset:
0011001111110011
Bit Symbol Bit Name Description R/W
b1, b0 TOPS[1:0] Timeout Period Select
b1 b0
0 0: 128 cycles (007Fh)
0 1: 512 cycles (01FFh)
1 0: 1024 cycles (03FFh)
1 1: 2048 cycles (07FFh)
R/W
b3, b2 Reserved These bits are read as 0. Writing to these bits has no effect. R
b7 to b4 CKS[3:0] Clock Divide Ratio Select
b7 b4
0 0 0 0: No division
0 0 1 0: Divide-by-16
0 0 1 1: Divide-by-32
0 1 0 0: Divide-by-64
1 1 1 1: Divide-by-128
0 1 0 1: Divide-by-256
Other settings are prohibited.
R/W
b9, b8 RPES[1:0] Window End Position Select
b9 b8
0 0: 75%
0 1: 50%
1 0: 25%
1 1: 0% (window end position is not specified.)
R/W
b11, b10
Reserved These bits are read as 0. Writing to these bits has no effect. R
b13, b12
RPSS[1:0] Window Start Position Select
b13 b12
0 0: 25%
0 1: 50%
1 0: 75%
1 1: 100% (window start position is not specified.)
R/W
b15, b14
Reserved These bits are read as 0. Writing to these bits has no effect. R