Introduction
This document contains API documentation for the diagnostic tests included MPLAB® Code Configurator AVR® IEC60730 Class B Diagnostic Library.
1 Software Requirements
2 Clock Frequency Test
This module contains functional safety diagnostics APIs for Clock Frequency test.
3 CPU Program Counter
This module contains functional safety diagnostics APIs for CPU Program counter test.
4 CPU Registers
This module contains functional safety diagnostics APIs for CPU Registers.
5 EEPROM - 16-bit CRC
This module contains APIs to calculate, store and validate 16-bit CCITT CRC for a given EEPROM region.
6 EEPROM - 32-bit CRC
This module contains APIs to calculate, store and validate 32-bit CCITT CRC for a given EEPROM region.
7 FLASH - 16-bit CRC
This module contains APIs to calculate, store and validate 16-bit CCITT CRC for a given FLASH region.
8 FLASH - 32-bit CRC
This module contains APIs to calculate, store and validate 32-bit CCITT CRC for a given FLASH region.
9 Interrupt Frequency Test
This module contains functional safety diagnostics API for Interrupt Frequency Test.
10 SRAM - Checkerboard Algorithm
This module contains functional safety diagnostics APIs for SRAM Checkerboard Test.
11 SRAM - March C-Minus Algorithm
This module contains functional safety diagnostics APIs for SRAM March-C Minus.
12 Simple Watchdog Timer
This module contains functional safety diagnostics APIs for WatchDog Timer Test.
13 Windowed Watchdog Timer
This module contains functional safety diagnostics APIs for WatchDog Timer Test.
14 File List
Here is a list of all documented files with brief descriptions
15 Class List
Here is a list of all documented files with brief descriptions

1.9 Simple Watchdog Timer

Test Name: Simple WDT Test.

Purpose of test: The watchdog timer (WDT) is a system function for monitoring correct program operation that allows recovering from error situations such as runaway or deadlocked code.

Acceptable Measure (Annex. H): Time-slot monitoring of the program sequence (H.2.18.10.4)

Description: The self-diagnostic routine verifies that,

System reset is issued after WDT timeout.
- This is done by setting up the WDT, and waiting until it issues a system reset. In addition, the TCA is used to estimate the watchdog period,which is required in later phases of the test. This is done by configuring the TCA with a small period and counting the number of TCA-periods until a system reset. If the program is left waiting for the system reset for longer than a configurable maximum timeout period, the error state is set.
WDT can be reset
- The second step is to make sure that the WDT can be reset, and to check the timing of the WDT. The error state is set. The test state will be in the error state until this step of the test is done. A check is performed to see that the estimated WDT period is higher than a minimum.

API Documentation: Simple Watchdog Timer