Kontron MSM-LP, Руководство пользователя

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MSM-LP / Special Features
4.4.2 Watchdog Hardware Access
The watchdog registers of the F81216 chip are accessible over I/O mapped registers with indexed access. The
following table shows the addresses used. The F81216 chip has few devices and the watchdog is device number 8.
Address Name Type Description
0x4E IND RW Indexed register access number
0x4F DAT RW Indexed register content
Indexed Register Map of Watchdog Device 08h
Index Bit Name Access Function
0x30 0 WDT_EN RW Watchdog device enable register: 0=disable,1=enable
0x30 1-7 RsvdP Reserved
0xF0 0 WDT_EVENT RO
0: no time out has occurred
1: time out has occurred
Writing "1" to this bit will clear the status
0xF0 1-2 WDT_UNIT RW
00: Timer Unit is 10ms
01: Timer Unit is 1 second
10: Timer Unit is 1 minute
11: reserved
0xF0 3-7 RsvdP Reserved
0xF1 7-0 WDT_CNT RW
The number of time units for the watchdog timer.
Write the same non-zero value twice to enable the timer; otherwise the timer is
disabled.
Register Attributes
Attribute Description
RsvdP RESERVED AND PRESERVED
Reserved for future RW implementations. Registers are Read-only and the software must preserve the value for
writes to this bit.
RW READ-WRITE REGISTER
Register bits are Read-Write and can be set or cleared by software.
RO READ-ONLY
Register bits are Read-only and can not be altered by software.
WO WRITE-ONLY
Register bits can only be Written. Reading returns indeterminable data.