SH3100IMTR SEMTECH [Semtech Corporation], SH3100IMTR Datasheet - Page 36

• Manufacturer Part Number: SH3100IMTR
• Description: Supervisory IC with I2C Interface and PWM
• Manufacturer: SEMTECH [Semtech Corporation]

© 2006 Semtech Corp.
POWER MANAGEMENT
Register Descriptions
Register Name CauseOfReset
Register Name WDTCode
Address(hex): 33
Address(hex): 34
Bit No.
Bit No.
Bit 7
Bit 7
[7:0]
[3]
[2]
[1]
[0]
Description
VBO
WDTCode
Violation
WDTExpired
PORB
Description
WDT refresh code
Bit 6
Bit 6
(continued)
Bit Value
Bit 5
Bit 5
0
1
0
1
0
1
0
1
Description
Value Description
VDD has not dropped below the programmed VBO level since this bit was last
cleared
VDD dropped below the VBO level at some point since this bit was last cleared.
Writing 1 to this bit clears it
Either the watchdog is disabled, or else only the correct code sequence has been
written in good time, to the WDTCode register
The watchdog was enabled, and an incorrect code was written to the WDTCode
register
Writing 1 to this bit clears it
Either the watchdog is disabled, or else WDTCode register has been refreshed in a
timely fashion
The watchdog is enabled, but the WDTCode register has not been refreshed in
time to prevent the watchdog expiring
Writing 1 to this bit clears it
VDD has not dropped below 1 V since this bit was last cleared
VDD dropped below 1 V at some time since this bit was last cleared
Writing 1 to this bit clears it
Description
Bit Value
Bit 4
Bit 4
WDTCode
36
(R/W) Shows what caused the
last reset
(R/W) Watchdog refresh code
Value Description
Once the watchdog is enabled by writing to the WDTPeriod
register, alternate writes of 5A and C3 are expected within the
time set by WDTPeriod and WDTPrescaler registers to prevent
NRESET activation. Once enabled, the watchdog can not be
disabled by software
Bit 3
Bit 3
VBO
WDTCode
Violation
Bit 2
Bit 2
Default Value: 0000 1001
Reset Event: (see description)
Default Value: 0000 0000
Reset Event: P, W, B
WDT expired
Bit 1
Bit 1
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SH3100
PORB
Bit 0
Bit 0