3.2.9 Dead Man Timer (DMT)
The Deadman Timer (DMT) module is designed to enable users to monitor the health of their application software by requiring periodic timer interrupts within a user-specified timing window.
The DMT module is a synchronous counter that, when enabled, counts instruction fetches and is able to cause a soft trap if the DMT counter is not cleared within a set number of instructions.
The DMT is typically connected to the system clock that drives the processor (TCY). The user specifies the timer time-out value and a mask value that specifies the range of the window, which is the range of counts that is not considered for the comparison event.
Using The Library
Some of the key features of this module are:
• Software Enabled
• User-Configurable Time-out Period or Instruction Count
• Two Instruction Sequences to Clear Timer
• 32-Bit Configurable Window to Clear Timer
Library Interface
Dead Man Timer peripheral library provides the following interfaces:
Functions
| Name | Description |
|---|---|
| DMT_Clear | Restarts the DMT counter |
| DMT_ClearWindowStatusGet | Returns Window is Open flag from the DMT Status Register |
| DMT_CounterGet | Returns the DMT current counter value |
| DMT_Enable | Enables the DMT peripheral |
| DMT_Intialize | Initializes the DMT peripheral |
| DMT_PostEventClear | Performs clear sequence for the DMT Event and all other DMT flags, post occurrence of DMT Event. |
| DMT_StatusGet | Gets the DMT peripheral status |
| DMT_TimeOutCountGet | Returns the DMT time-out count value |
| DMT_WindowIntervalGet | Returns the DMT window interval value |