Watchdog - MSC IPC370T Operating Instructions Manual

Installation and Configuration
2.4

Watchdog

In the BIOS set-up the following setting options are intended for the watchdog.
Address:
Three I/O addresses are offered for selection
over which the application software can access to the watchdog.
Timeout:
Can be set from 400 milliseconds until 600 seconds.
Within the set time, the watchdog must be triggered by the application,
otherwise a RESET is caused.
Delay:
Can be set from 1 until 1800 seconds.
The set time is bided after the start of the watchdog for one time,
until the timeout counter begins to count.
The application software can access to the watchdog register via the set I/O address
with IN and OUT commands.
ISA bus Designation
Bit 0 RUN (R/W)
Bit 1 TRIGGER (R/W)
Bit 2 TIMEOUT (R)
Furthermore the watchdog can be addressed via the I
In this case timeout and delay counters can be loaded by the application software.
Starting and triggering of the watchdog is only possible by the manner as described above.
2
Watchdog I C interface: Device address = B0h/B1h
The watchdog consists of individual byte registers.
Write:
Read :
For writing the watchdog must not have been started (Bit 0 via I/O = 0)
Address
0 TimeOut Low Byte
1 TimeOut High Byte
2 Delay Low Byte
3 Delay High Byte
Settings in the VIA Southbridge 82C686: Device 7 Function 0: Rx76[1] = 1 Rx8B[0] = 1
Rx[79] and Rx[78] contains the I/O addresses
e.g.:
Page 16 of 38
Description
1 = Timeout counter counting.
Change 0 on 1 resets TIMEOUT (Bit2) and initializes all counters.
must be toggled within the set time period
in order to reset the timeout counter.
0 = no timeout. Default after Power-Up or after setting Bit0.
1 = Timeout is occurred. Reset was caused.
With timeout the watchdog is stopped.
Device address B0h, register address, data byte
not possible
Data Byte Reset Condition Read/Write
100d
0
100d
0
Rx[79] = 03
Rx[78] = 00 corresponds to address 300H
2
C bus.
Bit
W Byte
W Byte
W Byte
W Byte
OI: IPC370T
Remark
Rev. 1.00 dated 1.7.2004