NXP Semiconductors
FXTH87E
FXTH87E, Family of Tire Pressure Monitor Sensors
= Reserved
Table 105.ꢀPWUS register field descriptions
Field
Description
Page Selection — The PSEL read/write bit selects whether the other bits are read from the WUT or PRST
counters. This bit is cleared by a power on reset that is not created by an exit from the STOP mode, but is
unaffected by other resets.
7
PSEL
0ꢀCSTAT = WUT counter status
1ꢀCSTAT = PRST counter status
6
Unused — An unused bit that always reads as a logical zero.
unused
Counter Status — These read-only bits show the status of the counter selected by the PSEL bit. The effects
of any reset on these bits depends on how the reset affects the selected counter. Reading these counters
immediately after a WUF or PRF generated flag will return zero contents.
5:0
CSTAT
13.6 Functional modes
PWU module will work in each of the MCU operating modes as follows:
13.6.1 RUN mode
If the module generates a wakeup interrupt the PC (Program Counter) will be redirected
to the wakeup timer interrupt vector. The WUF flag will be set to indicate wakeup timer
interrupt; write 1 to WUFACK to clear this flag.
If the module generates a reset the PC will be redirected to the reset vector. The PRF
flag will be set to indicate periodic reset; write 1 to PRFACK to clear this flag.
All registers will continue to hold their programmed values after interrupt or reset is taken.
13.6.2 STOP4 mode
If the module generates a wakeup interrupt the bus and core clocks will be restarted and
the PC will be redirected to the wakeup timer interrupt vector. The WUF flag will be set to
indicate wakeup timer interrupt, write 1 to WUFACK to clear this flag.
If the module generates a periodic reset the bus and core clocks will be restarted and
the PC will be redirected to the reset vector. The PRF flag will be set to indicate periodic
reset; write 1 to PRFACK to clear this flag.
All registers will continue to hold their programmed values after interrupt or reset is taken.
13.6.3 STOP1 mode
If the module generates a wakeup interrupt the module will cause the MCU to exit the
power saving mode as a POR. MCU will have the wakeup interrupt pending and once
CLI opcode is executed PC will be redirected to wakeup interrupt vector address. The
WUF flag will be set to indicate wakeup timer interrupt, write 1 to WUFACK to clear this
flag.
FXTH87ERM
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© NXP B.V. 2019. All rights reserved.
Reference manual
Rev. 5.0 — 4 February 2019
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