Mcwdt Interrupts; Pre-Warning Interrupt; Mcwdt Subcounter 2 Interrupt; Timeout Mode - Infineon XMC7000 Series Using Manual

Using the Watchdog Timer in XMC7000 family MCUs
Multi-counter WDT
Subcounter 0 and Subcounter 1: CTL, LOWER_LIMIT, UPPER_LIMIT, WARN_LIMIT, CONFIG, SERVICE, and CNT
registers
MCWDT_LOCK = 1
•
MCWDT_LOCK = 2
•
To protect the MCWDT registers, one single write access to the LOCK register is required:
MCWDT_LOCK = 3
•
3.3

MCWDT interrupts

MCWDT supports different types of interrupts.
3.3.1

Pre-warning interrupt

Subcounter 0 and Subcounter 1 behave very similarly to the pre-warning interrupt of the Basic WDT. See
Warning interrupt. The only difference is that the WARN_LIMIT is a 16-bit value that can generate an interrupt
timing per the following equation:
��������_����������
�� =
��������_������
��
����������
The interrupt can be used as a pre-warning event that indicates that the MCWDT counter must be serviced
before a FAULT event is issued.
The interrupt is triggered to the related CPU when the WARN_ACTION[8] bit is set to '1' in the CONFIG register.
The MCWDT can be serviced automatically by the AUTO_SERVICE[12] bit in the CONFIG register. This allows the
creation of a periodic interrupt if this counter is not needed as a watchdog.
3.3.2

MCWDT Subcounter 2 interrupt

Subcounter 2 interrupt behaves in a different way. A coarse-grained timing should be generated when a
dedicated pre-defined counter bit is toggled. The interrupt timing is calculated with the following equation:
1
��
�� = 2
������
��
����������
Example:
LFCLK = ILO0 = 32.768 kHz
Toggle-Bit = Bit 12
1
12
�� = 2 = 125 ����
������
32768
The toggle-bit is configured by BITS[20:16] in the CTR2_CONFIG register. The interrupt is triggered to the
related CPU when the ACTION[0] bit is set to '1' in the CTR2_CONFIG register.
3.4

Timeout mode

This mode is related to Subcounter 0 and Subcounter 1 only, and is similar to that of the basic WDT. See
2.5 Timeout mode. The difference is that the UPPER_LIMIT is a 16-bit value; when the subcounter matches with
the UPPER_LIMIT value, a FAULT is generated to be handled in the FAULT structures.
Application Note 15 of 33
2.4
002-33887 Rev. *A
2022-05-25