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IWDT register functional description
These peripheral registers can be operated by half word (16 bits) or word (32
bits).
Key register (IWDT_KEY)
Offset address: 0x00
Reset value: 0x0000 0000 (reset in standby mode)
Field
Name
R/W
Description
15:0
KEY
W
Allow Access IWDT Register Key Value
Writing 0x5555 means enabled access to IWDT_PSC and IWDT_CNTRLD
registers;
When the software writes 0xAAAA, it means to execute the reload counter,
and a certain interval is required to prevent the watchdog from resetting.
Write 0xCCCC and the watchdog will be enabled (the hardware watchdog is
unrestricted by this command word);
This register is write-only and the read-out vlue is 0x0000.
31:16
Reserved
Prescaler register (IWDT_PSC)
Offset address: 0x04
Reset value: 0x0000 0000
Field
Name
R/W
Description
2:0
PSC
R/W
Prescaler Factor Configure
Support write protection function; when writing 0x5555 in the IWDT_KEY
register, it is allowed to access the register; in the process of writing this
register, only when IWDT_STS register PSCUFLG=0, can the prescaler
factor be changed; in the process of reading this register, only when
PSCUFLG=0, can the read-out value of PSC register be valid.
000: PSC=4
001: PSC=8
010: PSC=16
011: PSC=32
100: PSC=64
101: PSC=128
110: PSC=256
111: PSC=256
31:3
Reserved
Counter reload register (IWDT_CNTRLD)
Offset address: 0x08
Reset value: 0x0000 0FFF (reset in standby mode)
Field
Name
R/W
Description
11:0
CNTRLD R/W
Watchdog Counter Reload Value Setup
It supports write protection function and defines the value loaded to the
watchdog counter when 0xAAAA is written by IWDT_KEY register; in the
process of writing this register, this register can be modified only when