Example Usage; Cpu Verification - Renesas RL78 Series Application Note

RL78 Family
3

Example Usage

In addition to the actual test software source files, the IAR Embedded Workbench test harness workspace is provided
which includes application examples demonstrating how the tests can be run. This code should be examined in
conjunction with this document to see how the various test functions are used.
The testing can typically be split into two parts:
1. Power-Up Tests.
These are tests can be run following a power on or reset. They should be run as soon as possible to ensure that
the system is working correctly. Tests that should be run are
1. All Ram using Initial March C (or initial March X)
2. All register tests
3. Flash Memory CRC Test
4. The clock test may be run at a later time depending on the initial clock speed if the maximum clock
speed is to be measured.
2. Periodic Tests.
These are tests that are run regularly throughout normal program operation. This document does not provide a
judgment of how often a particular test should be ran. How the scheduling of the periodic tests is performed is
up to the user depending upon how their application is structured.
1. Ram tests. These tests should use the "system" Ram test modules as these are designed to test the
2. Register Tests. These are dependant upon the application timing
3. Flash memory test. These modules are designed to be able to accumulate a CRC result over a
4. The clock test modules can be run at any time to suit the application timing
The following sections provide an example of how each test can be used.

3.1 CPU Verification

If a fault is detected by any of the CPU tests then this is very serious the aim of should be to get to a safe operating point,
where software execution is not relied upon, as soon as possible.
3.1.1 Power- Up Tests
All the CPU tests should be run as soon as possible following a reset.
3.1.2 Periodic
If testing the CPU registers periodically the function are designed to be run independently and so can be
operated at any time to suit the application. Each function restores the original register data on completion of
test so as not to corrupt the operation of the application system. It is important that interrupts are disabled
during these tests
R01AN0749EG0201 Rev.2.01
Mar 04, 2014
memory in small once the system is initialised. They can be used in small in order to
minimise the size of the buffer area needed to save the application data.
number of passes. In this way they can be used to suit the system operation
VDE Certified IEC60730/60335 Self Test Library
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