Watchdog Timer Drivers

NuttX supports a low-level, two-part watchdog timer driver.

1. An “upper half”, generic driver that provides the common watchdog timer interface to application level code, and

2. A “lower half”, platform-specific driver that implements the low-level timer controls to implement the watchdog timer functionality.

Files supporting the watchdog timer driver can be found in the following locations:

• Interface Definition. The header file for the NuttX watchdog timer driver reside at include/nuttx/timers/watchdog.h. This header file includes both the application level interface to the watchdog timer driver as well as the interface between the “upper half” and “lower half” drivers. The watchdog timer driver uses a standard character driver framework.

• “Upper Half” Driver. The generic, “upper half” watchdog timer driver resides at drivers/timers/watchdog.c.

• “Lower Half” Drivers. Platform-specific watchdog timer drivers reside in arch/<architecture>/src/<hardware> directory for the specific processor <architecture> and for the specific <chip> watchdog timer peripheral devices.