Chapter 6
IEC60730B tests
The library contains the following tests:
• Analog I/O test
• Clock test
• CPU register test
• Digital I/O test
• Invariable memory (flash) test
• Variable memory (RAM) test
• Program counter test
• Stack test
• Watchdog test
• Touch-sensing peripheral TSIv5 test
The following chapters describe each test with focus on the example application (debugging).
6.1 Clock test
The clock test procedure tests the oscilator frequency for the CPU core in the wrong frequency condition.
The default clock setting from the SDK library is used in the example. For a real application, ensure that the
reference clock source is not dependent on the primary (tested) clock.
NOTE
6.2 CPU register
The CPU register test procedure tests all CPU registers for the stuck-at condition (except for the program counter register). The
program counter test is implemented as a stand-alone safety routine.
Some tests stay in an endless loop in case of an error, others return a corresponding error message.
6.3 DIO test
The Digital Input/Output (DIO) test procedure performs the plausibility check of the processor's digital IO interface.
Make sure that the time between the "set" and "get" functions is sufficient for the GPIO peripheral speed.
NOTE
6.4 Invariable memory test
The invariable (Flash) memory test provides a CRC check of a dedicated part of memory. This test can be turned off in the
safety_config.h
file.
The test consists of the following two parts:
• Post-build CRC calculation of the dedicated memory.
• Runtime CRC calculation and comparison with the post-build result.
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