2.31 Dead Man Timer (DMT)
The primary function of the Deadman Timer (DMT) is to reset the processor in the event of a software malfunction. The DMT is a free-running instruction fetch timer, which is clocked whenever an instruction fetch occurs until a count match occurs. Instructions are not fetched when the processor is in Sleep mode.
The DMT consists of a 32-bit counter with a time-out count match value as specified by the DMTCNT<3:0> bits in the DEVCFG1 Configuration register.
A Deadman Timer is typically used in mission critical and safety critical applications, where any single failure of the software functionality and sequencing must be detected
Library Interface
Dead Man Timer peripheral library provides the following interfaces:
Functions
| Name | Description |
|---|---|
| DMT_Enable | Enables the DMT peripheral |
| DMT_Disable | Disables the DMT peripheral |
| DMT_ClearWindowStatusGet | Returns Window is Open flag from the DMT Status Register |
| DMT_CounterGet | Returns the DMT current counter value |
| DMT_TimeOutCountGet | Returns the DMT time-out count value |
| DMT_WindowIntervalGet | Returns the DMT window interval value |
| DMT_Clear | Restarts the DMT counter |