
W83637HF
Publication Release Date: June 25, 2003
- 35 -
Revision 1.3
6.6.3 The W83637HF temperature sensor 1(SYSTIN) SMI# interrupt has two modes
(1) Comparator Interrupt Mode
Setting the T
HYST
(Temperature Hysteresis) limit to 127
°
C will set temperature sensor 1 SMI# to
the Comparator Interrupt Mode. Temperature exceeds T
O
(Over Temperature) Limit causes an
interrupt and this interrupt will be reset by reading all the Interrupt Status Register. Once an
interrupt event has occurred by exceeding T
O
, then reset, if the temperature remains above the
T
O
, the interrupt will occur again when the next conversion has completed. If an interrupt event
has occurred by exceeding T
O
and not reset, the interrupts will not occur again. The interrupts will
continue to occur in this manner until the temperature goes below T
O
. (Figure 6.11)
Setting the T
HYST
lower than T
O
will set temperature sensor 1 SMI# to the Interrupt Mode. The following
are two kinds of interrupt modes, which are selected by Index 4Ch bit5:
(2) Two-Times Interrupt Mode
Temperature exceeding T
O
causes an interrupt and then temperature going below T
HYST
will also
cause an interrupt if the previous interrupt has been reset by reading all the interrupt Status
Register. Once an interrupt event has occurred by exceeding T
O
, then reset, if the temperature
remains above the T
HYST
, the interrupt will not occur. (Figure 6.12)
(3) One-Time Interrupt Mode
Temperature exceeding T
O
causes an interrupt and then temperature going below T
HYST
will not
cause an interrupt. Once an interrupt event has occurred by exceeding T
O
, then going below
T
HYST,
an interrupt will not occur again until the temperature exceeding T
O
. (Figure .6.13)
T
OI
T
1HYST
*
*
*Interrupt Reset when Interrupt Status Registers are read
T
OI
T
HYST
SMI#
SMI#
*
*
*
*
*
Figure 6.11
Figure 6.12