24.6 Generated resets and interrupts
The watchdog generates a reset in the following events, also referred to as exceptions:
• A watchdog time-out
• Failure to unlock the watchdog within WCT time after system reset deassertion
• No update of the control and configuration registers within the WCT window after
unlocking. At least one of the following registers must be written to within the WCT
window to avoid reset:
• WDOG_ST_CTRL_H, WDOG_ST_CTRL_L
• WDOG_TO_VAL_H, WDOG_TO_VAL_L
• WDOG_WIN_H, WDOG_WIN_L
• WDOG_PRESCALER
• A value other than the unlock sequence or the refresh sequence is written to the
unlock and/or refresh registers, respectively.
• A gap of more than 20 bus cycles exists between the writes of two values of the
unlock sequence.
• A gap of more than 20 bus cycles exists between the writes of two values of the
refresh sequence.
The watchdog can also generate an interrupt. If IRQ_RST_EN is set, then on the above
mentioned events WDOG_ST_CTRL_L[INT_FLG] is set, generating an interrupt. A
watchdog reset is also generated WCT time later to ensure the watchdog is fault tolerant.
The interrupt can be cleared by writing 1 to INT_FLG.
The gap of WCT between interrupt and reset means that the WDOG time-out value must
be greater than WCT. Otherwise, if the interrupt was generated due to a time-out, a
second consecutive time-out will occur in that WCT gap. This will trigger the backup
reset generator to generate a reset to the system, prematurely ending the interrupt service
routine execution. Also, jobs such as counting the number of watchdog resets would not
be done.
24.7 Memory map and register definition
This section consists of the memory map and register descriptions.
Generated resets and interrupts
K22F Sub-Family Reference Manual , Rev. 3, 7/2014
520
Freescale Semiconductor, Inc.
Содержание MK22FN256VDC12
Страница 2: ...K22F Sub Family Reference Manual Rev 3 7 2014 2 Freescale Semiconductor Inc...
Страница 136: ...Human machine interfaces K22F Sub Family Reference Manual Rev 3 7 2014 136 Freescale Semiconductor Inc...
Страница 164: ...Module clocks K22F Sub Family Reference Manual Rev 3 7 2014 164 Freescale Semiconductor Inc...
Страница 246: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 246 Freescale Semiconductor Inc...
Страница 328: ...Kinetis Flashloader Status Error Codes K22F Sub Family Reference Manual Rev 3 7 2014 328 Freescale Semiconductor Inc...
Страница 360: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 360 Freescale Semiconductor Inc...
Страница 388: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 388 Freescale Semiconductor Inc...
Страница 402: ...Initialization application information K22F Sub Family Reference Manual Rev 3 7 2014 402 Freescale Semiconductor Inc...
Страница 500: ...Initialization application information K22F Sub Family Reference Manual Rev 3 7 2014 500 Freescale Semiconductor Inc...
Страница 670: ...Flash memory map for EzPort access K22F Sub Family Reference Manual Rev 3 7 2014 670 Freescale Semiconductor Inc...
Страница 680: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 680 Freescale Semiconductor Inc...
Страница 744: ...Application information K22F Sub Family Reference Manual Rev 3 7 2014 744 Freescale Semiconductor Inc...
Страница 784: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 784 Freescale Semiconductor Inc...
Страница 794: ...Initialization Application Information K22F Sub Family Reference Manual Rev 3 7 2014 794 Freescale Semiconductor Inc...
Страница 960: ...Example configuration for chained timers K22F Sub Family Reference Manual Rev 3 7 2014 960 Freescale Semiconductor Inc...
Страница 1036: ...Device mode IRC48 operation K22F Sub Family Reference Manual Rev 3 7 2014 1036 Freescale Semiconductor Inc...
Страница 1040: ...USB Voltage Regulator Module Signal Descriptions K22F Sub Family Reference Manual Rev 3 7 2014 1040 Freescale Semiconductor Inc...
Страница 1094: ...Initialization application information K22F Sub Family Reference Manual Rev 3 7 2014 1094 Freescale Semiconductor Inc...
Страница 1128: ...Initialization application information K22F Sub Family Reference Manual Rev 3 7 2014 1128 Freescale Semiconductor Inc...
Страница 1216: ...Application information K22F Sub Family Reference Manual Rev 3 7 2014 1216 Freescale Semiconductor Inc...
Страница 1298: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 1298 Freescale Semiconductor Inc...
Страница 1312: ...K22F Sub Family Reference Manual Rev 3 7 2014 1312 Freescale Semiconductor Inc...